Veterinary Surgery by EuroVeterinarian Community

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TUFTS UNIVERSITY LIBRARIES

3 9090 014 531

Webster Famiiv Library

of Veterinary Medicine.

368

VETERINARY SURGERY Bv Louis A. Merillat,

Volume

V. S.

ANIMAL DENTLSTRY AND DISEASES OF

THE MOUTH

VETERINARY SURGERY By LOUIS

MERILLAT,

Volume

V. S.

ANIMAL DENTLSTRY AND DISEASES OF THE MOUTH

Volume H

THE PRINCH'LES OF VETERINARY SURGERY

VOLUM3 HI

VETERINARY SURGICAL OPERATIONS

lDetcrinar\> ©uroeri^

Voi-UME

ANIMAL DENTISTRY AND

DISEASES OF THE MOUTH

Louis A. Merillat^ V. S. PROFESSOR OF VETERINARY SURGERY IN THE CHICAGO VETERINARY COLLEGE LATE SECRETARY AND PROFESSOR OF DENTISTRY IN THE MKILLIP VETERINARY COLLEGE LATE PRESIDENT OF THE CHICAGO VETERINARY SOCIETY SECRETARY OF THE ASSOCIATION OF VETERINARY FACULTIES AND EXAMINING BOARDS OF NORTH AMERICA MEMBER OF THE AMERICAN VETERINARY MEDICAL ASSOCIATION; MEMBER OF THE ILLINOIS STATE VETERINARY MEDICAL SOCIETY, ETC. ;

;

Ifllustratc^

CHICAGO:

ALEXANDER EGE: 1908

Entered according

Act of Congress,

in the

year 1905, by

ALEXANDER EGER aD

office of the

Daniels Company Press, Chicago

Librarian

Congress

Washington.

To Mr.

MYRON

TICHENOR and

Mr.

LOUIS M. NEWCAS,

Chicago, U. S. A., for their appreciation of the varw^ dentistry on valuable coach

and saddle horses,

this

^.i

animal

volume

re-

spectfully dedicated by

The Author.

PREFACE. The domain large

of animal dentistry

volume without entering

today ably covered by each,

v/riters

would appear ridiculous

to "venture

where angels

ferent periods of

ment

life,

since these sciences are

merit

possessing special

for a veterinary practitioner

fear to tread."

understanding of the teeth

fill

into the details of embryol-

anatomy and physiology, and

ogy,

too limited to

in their

normal

comprehensive

state at the dif-

as a foundation for the intelligent treat-

of their abnormalities

is,

however, so essential that

has been thought advisable to include an epitome of these sciences so far as they appertain to the teeth.

This Volume, with Volumes

earnest solicitation of the students

and I

have had the privilege

of teaching during the past twelve years, is

the only excuse for

dentistry

publication.

its

given but limited space

written at the

III, is

which circumstance

The in

fact that

animal

the surgical litera-

ture of the profession has not entered into the proposition,

because the task of writing books belongs to those having the time and inclination to ponder leisurely over each single

and not to the busy practitioner, whose few

topic,

moments It

fact

are usually interrupted by "a call to action."

has been the aim to cover the subject

manner, excluding

ditions

idle

and including

routine of practice. illustrations,

all

in a

matter-of-

obscure, rare and imaginary con-

the conditions encountered in the

For compiling the index and

for the

which are made from copies and original draw-

PREFACE.

^ inj^s.

particularly indebted to Mr.

.\le.\.

Ki;er.

have

my friend, Dr. \\'. L. Williams. Professor of the New York State Veterinary College, for his

also to thank

Surgery

valuable suggestions as to the origin of teratoniata of the

mastoid region, and for his

many

brother Professor, Edw.

original ideas

Alerillat,

which are entered throughout

the text with but a single credit,

viz.,

the operation for clos-

ing skull perforations.

With ble

a full

knowledge that the manuscript would crum-

from the assault

of a literary critic,

forthwith apologize

to the censors of English veterinary literature.

L. A.

AlERILLAT.

CONTENTS. PAGE

Preface

Introduction

Chapter

18-43

Nomenclature

Teeth Divisions of a Tooth Structures of the Teeth

Chapter

44-67

Evolution of the Teeth Embryonic Evolution Evolution of the Temporary Teeth Evolution of the Permanent Teeth

Chapter

44 49

III

58 ,

68-126

Retrogression of the Temporary Teeth Retrogression of the Permanent Teeth

68 68

Determination of Age Routine of Examination of a Horse's Mouth to Determine Age Anomalies of the Teeth, Natural and Artificial

Chapter IV

117

127-132

Function of the Teeth

127

Chapter V Dental Diagnosis Dental Instruments

74 113

133-151 133

â&#x20AC;&#x201D; Their

Uses

Restraint

135

148

Chapter VI

152-256

Diseases and Irregularities of the Teeth Necrosis of the Teeth of Herbivora

152

Caries

172

Abnormal Eruptions

of the

Teeth

152 175

Dental Cysts

177

Odontomata

178

Brachygnathism Prognathism Parvignathism Projections on First Superior and Sixth Inferior Molars Projections on the Superior Corners Acquired Elongations of the Molars

179 181

182 184 185 185

Enamel Points

187

Wolf Teeth

202

CONTENTS.

xii

PAGE 204

Supernumerary Teeth Elongation of Incisors Erosion of Enamel Tartar Fracture of the Teeth Splitting of the Molars Foreign Bodies in the Mouth Fracture of the Inferior Maxilla Fractures of the Pre-Maxilla and Superior Maxilla Dislocation of the Temporo-Maxillary Articulation Bit Gnathitis

Osteomata of the Superior Maxilla Carcinomata of the Palate Sarcomata of the Mouth

207 208 208

209 209 210 211

213 213 214 216 217

217

Actinomycosis Dental Teratomata Dental Fistulae

218

Traumatic Stomatitis

226

Stomatitis

222 224

â&#x20AC;&#x201D; Infectious

Ulcerative Gingivitis of

227

Dogs

Retention Cysts

229 230

Lampas

230

Secondary Chronic Nasal Catarrh Chronic Perforation of the Skull Application of Gutta Percha Plugs Cribbing and Wind-Sucking

231

Habitual Ptyalism Side-Reining Habitual Protrusion of the Tongue

241

Bit

Lugging

236

238 239 242

244 245

Facial Paralysis

248

Lacerations of the Lips

249

Ranula

250

Foreign Bodies in the Tongue 250 Frost Bites, Laceration of the Cheeks and Tumors of Lips and

Cheeks Laceration and Inflammation of Tongue Aberrations of the Function of Mastication

251

252 253

INTRODUCTION. Dentistry

Human

their utiHty.

ing

the art of repairing the teeth or improving dentistry embraces the art of supply-

artificial substitutes for

the teeth

when

the original ones

are lost, while animal dentistr}- includes the therapeutics of

secondary pathological

the

mouth and

and lesions

processes

nasal cavities, caused by the teeth. It

essentially a mechanical rather than a

and

is,

the

however,

surgical departure,

a preventive rather than a curative effort.

province

Its

ends with the teeth and their immediate environs.

Dis-

orders of the digestion or impairment of the general health,

although directly traceable to the teeth, cannot be included

The

within the domain of dentistry. dentistry

principal

ol)ject

promote the general health by improving the

mastication and by relieving pain.

also aims at the pre-

servation of the juvenile appearance, to which the animal dentist

adds

the

amelioration

the

driving

defects

horses.

Human

dentistr}^

owes

its

existence to a single disease

process, caries, while animal dentistry depends

art

;

no*^

wouhl never have existed as an advanced

because there are no other serious abnormalities

within the domain of dentistry, ties are infrequent.

Init

because other abnormali-

Few mature human

beings escape caries,

and few mature herbivora escape enamel points. wide requirement for dental operations

and tion,

a single

Without these two abnor-

physical defect, enamel points. malities dentistry

upon

in the chief

domestic animal

in the

â&#x20AC;&#x201D;the horse.

human As

replacement and repair of the decayed tooth

occupation of the

human

dentist, so 13

Hence

the

family,

the extracis

the chief

cutting and floating

ANIMAL DENTISTRY.

enamel

jioints the j)i'incipal

work

animal dentist.

of the

student of zoology will deny that the domestic herbivora, especially the horse, suffers from frightful physical defects that are inimical to their o-eneral health

and usefulness.

The

other defects and diseases, although frequently of s'erious

demand only

import,

a small share of the animal dentist's

attention because they are relatively

The

rare.

ovine, and l)Ovine species do not suffer to the

porcine,

same extent

as the domestic horse on account of their different occupa-

and short

tion

life.

genera seldom

live

Except

beyond

breeding purposes these

for

their maturity,

they are not submitted to the same

and even then

artificial influences as

In the canine and feline species the anatomical con-

horse.

stitution of the teeth prevents projecting defects

short

the

life

and their

precludes caries, so here again the animal dentist

meets only an occasional condition demanding attention. It is

ters

evident, therefore, that animal dentistry naturally cen-

upon the horse, the commercial value

which depends

much upon its utility as upon its general appearance. And again, mastication and insalivation are two essential as

digestive processes in herbivora, and of

tance than

carnivora and or.uiivora.

relative impor-

The coarse amy-

laceous food of herbivora, especially the non-ruminating herbivora,

requires

immediate and perfect comminution and

incorporation with saliva to insure perfect gastric digestion

and subsequent absorption, while the food of

man may without

rectly to the

may be consume

special

stomach with but

little

said of the dog, the cat their food -vvithout a

artificially

prepared

detriment be passed mastication.

and the hog,

all

di-

The same of

which

semblance of persistent mas-

tication.

Then again, animal dentistry must respect the horse's mouth as the "seat of the l)it" as well as the mechanism of mastication. The manner in which the horse accepts the bit

ANIMAL DENTISTRY. must always be

determining factor

dental defects which irritate or

X5 in

wound

its

The

value.

the buccal surfaces

under the pressure of the complicated riggings of harness

and saddle horses constitute an important feature

animal

dentistry.

A summary

of the exact scope of animal dentistry

follows 1st.

The

cutting and floating of the enamel points of the

horse and ox. 2nd.

The removal

which prevent perfect

of projections

apposition of the dental arcades of the horse, ox and hog. 3rd,

The treatment

from diseased 4th. 5th.

secondary nasal catarrh resulting

teeth.

The extraction of all diseased teeth of The removal of tumors related to the

animals.

all

teeth, in

all

animals. 6th.

The treatment

of stomatitis caused

by the

bit or

dental projections. 7th.

The amelioration

of driving defects resulting

from

dental irregularities in the horse. 8th.

The treatment

of faulty eruptions of the

nent or temporary dentures

perma-

the dog, the horse, the ox and

the cat. 9th.

Improving the appearance

of the incisors

the

horse.

When

dentistry in animals

as an important tics,

are

more generally recognized

not essential feature of animal therapeu-

and when dental operations by reason

made

easier, the veterinarian will

dentistry with the

surgery.

One

same dignity

as the other branches of

object of this volume

of animal dentistry

of greater skill

then treat the art of

to popularize the art

by describing easy methods

ing dental operations

;

perform-

by drawing attention to the value and

necessity of dentistry, and by pointing out the advisability

ANIMAL DEXTISTRV.

16 of sacredly

ijnardinc;-

dentistry from becominj:^ obsolete in

the veterinary profession, and from passinc^ to the willing

who, through

specialist,

deficient

fundamental technical edu-

cation cannot keep pace with the

being made

the other branches of veterinary surgery.

Animal dentistry difficult,

advancement continually

unpopular, not so

much because

tedious and even dangerous, Imt because

garded as of minor importance

and by the better

re-

the veterinary colleges

class of veterinary practitioners,

who

will-

ingly stigmatize animal dentistry as an unimportant "side

by relegating dental operations

issue"

assistant, the

to the student, the

stable-helper, the horse-shoer or the horse-

dentist.

Only

few years ago,

urgent rec|uest of

a suffering

would condescend

to pull an

at the

patient, the family physician

aching tooth, but he was never specially provoked patient had consulted the in

many

localities

tooth-pullers,

new

such a

watchmaker or the locksmith, who

had earned enviable reputations as expert

and who

i)rofession of

finally

human

became the

dentistry.

first

The duty

recruits in the of the veteri-

narian of today toward the tooth-rasping horse-shoer or the professional horse-dentist 1)ears a striking resemblance to the relations between the physician and tooth-pulling lock-

smith of a few years ago.

The

able physician in those davs

willingly consigned the tooth-ache patient to the locksmith,

or the barber, or the watchmaker, l)ecause dental operations

were then considered as an unimportant "side

issue," rather

beneath the dignity of the learned therapeutist. spite of this apathy, dentistry asserted

its

But,

importance and

soon became a part of the curriculum of the foremost universities of the world.

This

The

precisely the status of animal dcntistrv today.

veterinarian consigns dental operations to others, be-

cause

rather beneath the dignity of the learned veteri-

ANIMAL DENTISTRY.

narian to float the teeth of horses: not because

is difficult,

tedious or dangerous, but because animal dentistry

garded as a

trifling

The

master.

re-

accomplishment that the uneducated can

intimate relation of the condition of the teeth

to the general health

becoming more and more recognized,

and when the value and importance

of veterinary dentistry

universally recognized public,

and when

l)y the veterinary profession and lay becomes more generally admitted on all

sides that the veterinary patient receives the

benefits

same

relative

from dental operations as the human subject, animal

dentistry will then take of veterinary science.

place

its

The

among

limited

the useful branches

number

of patients will

probably always prevent the evolution of animal dentistrv

The

into a special profession.

be required to perfect himself

There were tion of

human

The same

veterinarian will, therefore,

the practice of this art.

tv/o potent factors

dentistry

â&#x20AC;&#x201D; the

concerned

the evolu-

college and the practitioner.

influences are essential to the healthy evolution of

animal dentistry.

The

college

must devote more time

the art and the practitioner must

become more

proficient,

even though the increasing importance of animal dentistry cannot be met by the birth of a new profession. deserves to be brought out more prominently ture on surgical subjects,

The

subject

in the litera-

order to foster and maintain

sesqui-special relations to veterinar}^ surgery as a whole.

its

CPiAPTER

NOMENCLATURE OF THE TEETH. The

teeth are called. Incisors, Canines, or Molars, ac-

cording to their location, form and function; they are superior or inferior according- to the

jaw into which they are im-

planted; and right or left according to the side of the n^icdian line of the

median ners.

body they occnpy. The

line

incisors,

naming from the

outward, are called centrals, laterals and cor-

The molars

are numbered,

Fk;.

ist,

2nd, 3rd,

from

etc.,

Complete Denture of a Horse. 1.

The Canine

Incisor denture.

Molar denture.

denture.

before b-ackward.

The

molars and

sess

n^.ola.rs

useless

int(~)

prc-

the herbivora, as thcv pos-

no distinguishing characteristics that woitld wai â&#x20AC;˘rant

such classihcation. and is

sul)division of the molars

more confusing than Each tooth

in the

the other animals the subdi\- ision

instructive.

head

n^.ay 18

then be identified by

r (ifer-

ANIMAL DENTISTRY. ring

the

"right-first-superior molar," the "left-

fourth-siiperior molar,"

the

"left-inferior canine." etc.,

'Meft-infcrior-lateral," or

the

throughout the dental arcades.

DIVISIONS OF A TOOTH. Anatomically a tooth

divided into the crown, neck,

fang, roots, table, infundibulum and cup.

the projecting portion, or in other

mal tooth that

visible.

The crown

words that part

The neck

refers to of a nor-

the part covered with

gums, or the part between the crown and alveolar margin.

The fang

imbedded portion or the part between the

the

veolar margin and the projecting roots.

The

al-

roots are the

small projections at the imbedded extremity of the fang.

The

table refers to the grinding or contact surface.

infundibulum

the cavity on the table produced by the in-

folding of the enamel, while the cup refers to the unfilled

portion of the infundibula of the incisors.

The

surfaces of the teeth are frequently referred to as the

"buccal surface," the "labial surface," or the "lingual surface."

In the case of the molars the buccal surface

the

external and the lingual, the internal, while in the incisors the lingual refers to the posterior surface, and the labial to the anterior.

Other names frequently used

the study of dentistry are

"alveolar margin," referring to the outer border of the alveolar cavity; the

"gingival margin," which refers to the outer

border of the gums, and "contact margin," which implies the cutting Ijorder of a tooth such as an incisor of carnivora.

STRUCTURES OF THE TEETH. A

tooth

composed

the former predominates in

hard and soft

tissues, of

volume and importance.

which

The

hard tissues comprise a body of dentine, capped with enamel.

ANIMAL

DlCXTIS'lkV.

encrusted over the rcmainiiif^ portion witli crusta pe-

aiid

trosa, or cement.

Tlie soft structures are the pulp, which

occupies a cavity within the 1)ody of the tooth, the aveolodental periosteum which surrounds the fano-, the

.churns

blood vessels which supply whicli furnish

tlie

external surface of

or gingivae, which cover the neck, the

its sensil)ility

its

and

nutrition,

and

nerves

the

tactile sense.

DENTINE. The

dentine

a hard, yel]o\\-ish, sensitive

substance con-

"f'j mm,'/

'iHiriilh'l

iMâ&#x20AC;&#x17E;lllul!.illlUI|ht|!,;l||((||K||||

Fig.

ta.

Enamel and Dentine as .Arranged the Crown. 1.

F.naniel.

Spaces of Czcrmak.

T'cntiiK?.

Fig.

(Magnified.)

stitutino- the

major

Dentinal Tnlndes. Ma'Jjnified.

])ortion of the

tooth's volume.

ex-

tends from the j)ulp cavity within to the enamel and crusta

petrosa without. sition

Chcnu'cally

shows the

followiu"-

compo-

Carbonate of lime Phosphate of lime Phosphate of magnesia Fluoride of lime

7-97 ^^'7-54

2.49 a trace

ANIMAL DENTISTRY.

Fats

58 20.42

Cartilage

Soluble salts

Microscopically

reveals a

homogeneous substance

per-

forated throughout with small canals (the dentinal tubules)

which anastomose freely with each other and extend out-

ward from the pulp

where they termi-

cavity to the surface

(the spaces of Czermak), which in

nate in large lacunae

turn communicate with the canaliculi of the crusta petrosa at the fang,

and cuticle of the enamel

The

crown.

at the

tubules are from four to five microns in diameter at the pulp cavity,

and one to

microns

t\\o

at the surface of the dentine.

ENAMEL. The enamel

the hardest of the dental tissues contain-

ing more than 96 per cent of inorganic matter.

ranged upon the dentine

in the

form

ar-

of a thin cap over the

crown and extending beyond the alveolar margin over part of the fang.

In the herbivorous animals

Fig.

known

depression

In the virgin

covers the entire table surface, but soon wears ofT at

that point from the

mastication of food, leaving only

edges projecting at the grinding surface. it

Molar of a Small Ruminant.

characteristic of these teeth, the infundibulum.

teeth

deeply

the First

folded into the table to form the well

The Enamel Organ Dissected from

Enamel (Magnified).

tooth

the outer covering of both the

surfaces, throughout the

life

its

In the incisor

lal)ial

and lingual

of the animal, but in the molars

ANLMAL DICXTISTRY.

22 it

soon hc'conics

l)otli

witli

The enamel

short time.

the incisors

co\'erin^" after

arranged

crnsta pctrosa on

The molar

the liuccal and lingual surfaces.

no outer enamel a

encrusted

lliicl<l_\-

they ha\-e been

teeth have in

the form of an oblong or elliptical

The

into a very irregular boundary.

an undulated

i)late

for

surrounding^ the infundibula of

ring at the table surface, ^^hilc that of the molars

sists of

wear

folded

external enamel con-

following the course of the longi-

tudinal ridges and groo\-es of the molar teeth.

end of the longitudinal ridges

terminates

At the

in a

constituting the "sharp teeth" of herbivora.

table

sharp point,

Chemically,

consists of

Carbonate of lime Phosphate of lime

4-37

89.82

Fluoride of lime

Phosphate

a trace

magnesia

1.34

Soluble salts

Organic matter Microscopically

3.59

presents a thin cutic'e or skin called

the cuticle of the enamel, which of enaniel

separable

when

a section

treated with hydrochloric acid, and hexagonal

prisms projecting at a right angle from the surface of the dentine, giving the appearance of a mosiac floor.

CRUSTA PETROSA OR CEMENT. The

crusta petrosa

composing the of the fang cavity.

the softest of the three hard bodies

It is

an external osseous incrustation

by which the tooth

Tn the \-irgin

tooth ages tissue.

teeth.

becomes

footh

cemented

but

to the alveolar

a thin layer,

but as the

thick from the deposition of osseous

Crusta peti'osa covers the entire outer surfaces of

the mature molars, the fangs of the incisors, the grooves in the crowns of the incisors of old animals and parllv

fills

the

ANIMAL DENTISTRY In animals having siniple teeth

iiifiindiljula.

the fangs.

Chemically,

Carbonate Phosphate

composed

of lime

'].22

of lime

48.73 a trace

magnesia

99 82

Soluble salts

4i-3i

Cartilage

Fats

Microscopically

Fig.

presents the typical characteristics of

Fig.

Dentine and Crusta Petrosa as Arranged at the Fang (Magnified). 1.

Crusta petrosa.

Spaces of Czermak.

Dentine.

Natural Cavities of a Molar. A.

Pulp

Infundibulum.

cavity.

the compact tissue of bone, the canaliculi of which cate with those of the dentine.

It is

in its

formation.

communi-

intimately associated

with the alveolo-dental periosteum, which

cerned

limited to

of:

Fluoride of lime

Phosphate

membrane

con-

ANLMAL IMvNTISTRV

THE PULP. The pulp

a piiltaceons sul).stance

of the pnlp cavity, consisting of loosely

blood

tissue,

vessels,

nerves

and

molded

to tlie sliape

arranged connective limiting

membrane

(odontogenic membrane) which sends processes throughout the entire length and course of the dentinal tubules, and

communicates with the alveolo-dental

periosteum

the

''<&/,"','M^

Fu;.

Arrangement of

t!ie

Dental Tissues

Internal enamel surrounding the infundibulum.

Pulp.

Dentine.

External enamel.

The pulp

apical foramen.

itself

Incisor.

acts as a support for the

blood vessels and nerves while the odontogenic membrane is

concerned

tooth construction.

In the teeth of herbivora

constantly depositing dentinal substance

the tubules

])eneath the table surface to destroy the sensibility of the

wearing dentine.

ALVEOLO-DENTAL PERIOSTEUM. The

alveolo-dental periosteum

a dense,

tough

mem-

brane consisting chiefly of white fibrous tissue and osteocovers the entire fang, communicates with the

blasts.

limiting

membrane

of the pulp at the apical foramen,

termingles intimately with the gun^s at

the

and

in-

neck of the

ANIMAL DENTISTRY. tooth.

fibers

Its

are continuous with the stroma of the

crusta petrosa and that of the alveolar wall, forming a firm

connecting medium betw^een the two. it

has

all

the characteristics of a

In the virgin tooth

membrane, but

soon loses

and becomes confused with the crusta petrosa,

this feature

which tissue

develops.

THE GUMS. The gums,

or gingivae,

may

be considered in the sense

of a hypertrophy, either of the buccal

mucous membrane or

of the alveolo-dental periosteum, to both of

intimately connected.

They

which they are

consist of dense fibrous tissue,

the fibers of which intermingle with the alveolo-dental peri-

osteum and crusta petrosa, with the purpose

of hermetically

sealing the alveolar cavities from external influences.

BLOOD VESSELS. The blood supply perior and carotid.

of the teeth

derived from the su-

inferior dental arteries, branches of the external

The

superior dental

given

lary, passes into the superior dental

ofif

the internal maxil-

foramen of the maxi!-

lary hiatus, through the superior dental canal as far as the infra-orbita! foramen, along the roots of the third, second

and

first

molars, and then through the premaxilla to the ca-

nines and incisors. it

Along the course

of the dental arcades

gives off branches, for each tooth, which pass into the

pulp cavity through the apical foramina. tal

The

inferior den-

artery has the same general distribution via the inferior

dental canal.

In addition to this principal blood supply teeth

receive nourishment from

way

surrounding

blood

vessels by

of the alveolo-dental periosteum to the extent of pre-

serving the integrity of the tooth should

be interrupted.

its

principal supply

AN'IMAL I)1-:\T1STRV

THE NERVES. The nerves

arc sensory aiul tactile, and are derived from

the snperior and

tlie

inferior maxillary 1)ranches of the tri-

Fu;. g.

Lncisor and Canine Teeth of a Mature Horse.

ANIMAL DENTISTRY.

28 facial.

They have

teries, the

the

same

g-eneral distribution as the ar-

courses of whicli they follow into the pulp cavity.

jiMii!l!ii!;i|[|tj|||||

|[jii|;ilj,j|lffllpiii'Ji jj|

Fk;.

Incisor Teeth of a

10.

Mature Horse. Anterior View.

PERMANENT INCISOR TEETH OF A HORSE. The

incisor tooth of a horse presents the

pyramid with the

form

of a

curved

q-reatcr curvature forward, the base out-

ward and the apex implanted deeply into the alveolar cavity

ANIMAL DENTISTRY of the

same shape.

sents the crown, it

becomes

finally

table

first

biangular it

The base elHptical,

of the

pyramid, which repre-

and measuring toward the apex

oblong, then triangular, then rounded and in

presents

the

external *

enamel

dentine,

internal

Tlie labial and lingual surfaces

Fig. II. a

At the

the antero-posterior direction.

enamel, and infundibulum.

Canine Teeth of

Fig.

Horse, Buccal Sur-

C-anine

Teeth

12.

Horse,

Lingual

Surfac

face.

Fig.

13.

Longitudinal Sections Through Incisor Teeth.

are covered with enamel which in youth

uninterrupted

with encrustations of either tartar or crusta petrosa, of a bluish-white color.

At the apex

and

presents a wide ope.n-

ANIMAL DENTISTRY

iyg

— the

apical

foramen

— for

the entrance- of l^lood vessels

and nerves. In sitn they are arranged

perfect juxtaposition in the

form of a symmetrical curve with the convexity forward,

and their contact with the opposing arcade

an obtuse

Xear the gingival margin they are separated by

angle.

processes of the gums.

The

lo.)

function of the incisor teeth

that has been gathered

Thev

of defense.

changes

(See Fig.

by the

that of detaching food

and to serve as weapons

lips,

are not concerned

mastication.

For

the teeth, see Chapter TTT.

THE CANINE TEETH OF THE HORSE. The

canine teeth exist only

permanent structures

They occur

teeth. in

The crown

occasionally as rudimentary

the mare, but never develop the typical canine

characteristics.

centimeter

males and occur only as

They

represent a curved tube about one

diameter, and flattened at one end flat

—the crown.

and presents internally two shallow per-

pendicular grooves divided by a rounded ridge. is

cylindrical

and the apical foramen round and

The canines, so less members which

far as digestion

The fang

large.

concerned, are use-

the horse could well do without.

are prol)al)ly intended as

weapons

of defense,

They

and may serve

to assist in passing coarse filjrous food from the incisors to

the molars.

THE MOLARS. The

superior molars rcsemlfle an elongated square block

description four surfaces, the table

They present for and apex. The external

three

prominent longitudinal

tapering slightly toward one extremity.

buccal

surface

ridges separated by

presents

two grooves,

entire length of the tooth,

all

which traverse the

and terminate

at the table in a

ANIMAL DENTISTRY.

The smooth and come crown only. The sharp point.

anterior and posterior surfaces are in

iiat

and

contact with contiguous surfaces at the

internal surface

quite

what convex from before backward.

smooth and some-

The

table presents

the external crusta petrosa, the external enamel, the dentine,

uhe internal enamel,

The edges letter

"B."

of the

and the internal crusta petrosa.

enamel are arranged

(See Figs.

i6, 17.)

the form of the

In the center of the internal

AXI.MAl. DK.v'riSTRV

The

superior molar a\era<4es 48 milliiiietcrs

I'lrst

the second 55 milHineters, the third

yi^

1<mi<^.

millimeters, the fourth

68 millimeters, the hfth 65 millimeters, and the

sixtii

60 to

63 millimeters.

The

inferior

molars are somewhat longer and much more In volume, tooth for tooth,

flattened than the superior ones.

the superior ones greatly exceed them.

smoother, their borders ridges

less

The

j^romincnt.

less

distinct,

Their surfaces are

and the longitudinal

longitu(hnal

ridges

the

Z5 M.M. Fig. 17

Fig. 16.

Tabic Surface of a Supcrifir Alolar, witli Measurement.

Arrangement of on

tlie

tlic

Dental Tissues

Talile of a .Superior

Alolar. I,

Infundibula.

Crusta petrosa.

l^entine.

Enamel.

internal or lingual surface are three in

nate

the

tables

sharp

enamel

the external ones of the superior molars. the is

same dental substances

arranged

number and points

The

termi-

similar

tables present

as the superior, but the

enamel

the form of an irregular figure, and not in

the shape of the letter "B," as on the superior tables.

enamel

but a single organ and

and external enamel, as

The

not divided into internal

the incisors and superior molars.

This arrangement leaves the inferior molars without perfectl}'

inclosed infundibula and allows

all

the crusta petrosa

ANIMAL DENTISTRY. communicate

org-an

This arrangement of the enamel

freely.

due to the fact that

That

superior.

is,

its

infolds are lateral

and not

the enamel does not dip deeply into the

table end, but folds inwards into great ruffles along each

They each have two

side.

roots, each of

which

pierced at

the apex with the foramen for the entrance of the vessels and nerves.

Fig.

i8.

Longitudinal

Through 1.

Section a

Molar.

Infundibuluni.

Dentine.

Crusta petrosa and

Fig.

enamel. Internal enamel.

Buccal

Fig. 20.

19.

Inferior Molar,

Inferior Molar, Lin-

gual Surface, with

Surface.

Measurement.

The

superior arcades are prominently convex on

the

external or buccal surface, and concave on the internal or

The width

lingual surface.

of the arcade

is.

uniform through-

out the entire length, with the exception of the extremities

which taper to

narrow border anteriorly and

a blunted

one

— ANLMi\L J)Jv\TISTRV

34 posteriorly,

meters

width between the arcades

'llic

57 millimeters at the

meters

The

milli-

at the sixth molars, 75 millimeters at the fourth,

lont^:

superior ones.

may even

are from 18 to 20 centi-

and average 25 to 28 millimeters wide.

inferior arcades are

fourth and

They

first.

fifth

They

more on

than the

a straight line

are but slightly curved outward at the

molars, while at the second and third they

present a slight inward curvature.

perior, they

and

have

Like the su-

uniform width with the exception of the

pointed extremities.

The width between

the arcades

millimeters at the sixth molars, 60 millimeters at the fourth

and about 50 millimeters

at the first.

They

are from 18 to

20 centimeters long and average 17 to 20 millimeters wide. ;7

Fig. 20.\.

Table Surface of an Inferior Molar, with Measurement.

and

superior and right

left

inferior

—

— right

and

left

each containing

six

In situ the molars present four arcades

teeth, juxtaposited so closely as to give the impression of

being a single body.

The

juxtaposition of the molars

of the important features of

bivorous animals.

mation of

dental

tlie

This feature adds

mechanism

one

of her-

materiall}'- to the for-

a perfect, as well as a stable, grinding apparatus.

Each arcade

from t8 to 20 centimeters

length.

THE PERMANENT INCISORS OF RUMINANTS. Ruminants have but one the superior l>eing replaced tissue.

The

incisor arcade

a dense

incisors are eight in

— the

pad

number,

inferior

of connective

identified, count-

Fig. 21.

Fig. 22.

Superior Molar Arcade of a Horse, with Measurement.

Inferior

Molar Arcade of a Horse, wifJi Measurement.

ANIMAL DEXTISTKV

36 \nv;

from the median

line

outward, as centrals, :

They resemble

mediates, and comers.

a tapering handle, are not juxtaposed

The fangs

imbedded

are

laterals, inter-

scoop or shovel with

and are always

the long necks are firmly attached to the gums.

very white

The

color.

loose.

into shallow alveolar cavaties

labial surface is

and

They

are

convex and the

lingual one concave to

fit

They diminish

from the centrals outward, the cor-

ners being

size

(juite

the dental pad on the premaxilla.

small.

Fig. 23.

Incisor

Denture of the Ox.

THE PERMANENT MOLARS OF RUMINANTS. The

superior molars of the large

those of the horse.

molars each as internal

are arranged in

in solipeds.

The

resemble

two arcades

of six

tables present the enamel,

and external, the crusta petrosa, dentine and the

infundibu'a.

arranged

They

ruminants

In the three posterior molars the enamel

the shape of the letter "B," as in the horse,

ANIMAL DENTISTRY.

while the three anterior ones present more the shape of a

"U" turned bottom

against the tongue.

The

molars have but one infundibulum, while the two.

The

first

last three

three

have

longitudinal ridges are prominent features of the

buccal surface and terminate at the table in sharp points.

Fig. 24.

Incisor Teeth of the Ox.

Lingual surface of lateral incisor.

Labial surface of central incisor.

Lingual surface of corner incisor.

Labial surface of intermediate

The length and that

incisor.

of the posterior molars

of the anterior

about 8J2 centimeters,

about 5V2 centimeters. Each tooth

presents three roots, two of which project externally and

one internally. In situ they consist of a continuous arcade, narrow anteriorly

and becoming gradually wider toward the posterior

ANIMAL DENTISTRY

Fig. 26.

Inferior ^lolar of an

(Labial

Fig.

Fic. 27.

25.

Molar Arcade of an Ox.

Superior

Surface).

Inferior

Molar of an

(Linp;ual Surface).

Animal dentistry.

They cannot be

extremity.

said to be as perfectly juxta-

posited as in the horse, as the internal surface of the arcades

The arcade

has deep depressions at the interdentia.

will

average 12 centimeters long and from 15 to 22 millimeters wide.

The

molars are very narrow and closely juxta-

inferior

posited, as in the inferiors of the horse, but in shape and

arrangement

The

ers.

of the

first is

enamel

from the oth-

differs

triangular in shape and contains but a single

The second and

ring of enamel. their

enamel each tooth

third are rectangular

and

arranged into the form of an irregular figure

The

havinp- five to six indentations.

fourth and

fifth

con-

Fu;. 28.

Tabic of sist

two

Superior Molar of the Ox.

lobes, each

having

central enamel ring and

infundibulum, while the sixth has three lobes w-ith central

enamel infundibula on the two anterior

measure from

11 to 15

The arcades

lobes.

The

millimeters wide.

first

three are

from 52 to 54 millimeters long- and the posterior three measure from 88 to 93 millimeters in length.

TEETH OF THE DOG. The dog has

ail

canines and six molars

six

incisors,

two

the superior jaw and six incisors,

two canines and seven molars the teeth of the

â&#x20AC;&#x201D;

forty-two teeth

dog are simple

in the inferior jaw.

teeth,

with enamel on the table through

e.,

life.

All of

they are covered

The

incisors are

small as compared with the other teeth, and they do not

contact each other until the dog

more than

year

old.

^ ^ :

AN'l.MAL I)1<:XTIS'1M<Y.

ANIMAL DENTISTRY.

The

canines are the prominent features of the dog's den-

ture.

They

are large, white

members having deep implan-

tations and elongated conical crowns curved backwards.

which pass each other

in a

manner

to grasp

and hold firmly .r-

I'TG.

Inferior

30.

Denture of a Dog.

(Cornevin

Lesbre.)

any object caught between them. very irregular, as inferior

also

molar of dogs

The molar denture is each individual tooth. The first

properly classified as a temporary

tooth that persists in the mature animal, although

fre-

quently referred to as a permanent tooth having no tern-

ANIMAL DEXTISTRV

porary predecessor.

'J'hc

first

and second inferior molars

have small conical crowns, slightly

ctit

out internally and

Fig. 31.

Superior

Denture

but a single root.

The

Aged Dog.

third

(Cornevin

Lcshre.)

and fourth present on the crown

one large cone anteriorly and two smaller ones posteriorly;

and each fang has two

roots.

The

fifth

has two small an-

ANIMATv DENTISTRY.

terior cones, three small posterior ones

on the crown, and

three roots.

The

sixth

inferior has

two roots projecting

backwards and presents a large crown with a number conical projections and a deep infundibulum.

The seventh

small but has three projections on the table and

The the

superior molars are six in

same general description

behind the

first,

number and

two will

of is

roots.

answer

as the inferior ones, located

but their crowns are wider and more beveled

from within outward.

CHAPTER

II.

EVOLUTION OF THE TEETH. The

teeth arc not a part of the skeleton and never, like

other juxtapositcd hard tissues, unite to each other or to the

bones that surround them. They originate from the mucous

membranes bones.

They

as horn, hair

The

mouth and develop independently of the appendages of the buccal mucosa precisely

of the

are

and hoof are appendages of the

evolution

(growth) of the teeth and their subse-

quent retrogression (wear) occurs sive stages

skin.

such distinct succes-

from embryo to old age that the age of animals

can be accurately determined at any period of

life.

The

stages of evolution and the stages of retrogression, however,

vary with each species

â&#x20AC;&#x201D; the

showing individual

cat each

evolution are distinct

all

horse, the dog, the

ox and the

The

characteristics.

stages of

species, while those of retro-

gression are onb/ apparent in the horse, the ox, the sheep

and the

pig.

The

dog, the cat and

distinct stages of wear,

owing

man show no

visible

to the different anatomical

construction of the teeth.

Dental

evolution

naturally

divides

itself

into

three

periods I

St.

The embryonic

evolution.

2nd.

Evolution of the temporary teeth.

3rd.

Evolution of the permanent teeth.

EMBRYONIC EVOLUTION. In the

embryo

of the

begins at the seventh

domestic

week

mammal

of foetal 44

life.

tooth formation

The

dental ap-

ANIMAL DENTISTRY, paratus at that time

represented by a whitened ridge of

mucous membrane extending around the maxillary margin. This ridge (gingival cushion) teeth develop.

two layers

At the

ranged

cells

the matrix from which the

earliest period

of epithelial cells

connective tissue.

The outer

consists chiefly of

and basement membrane

layer consists of loosely ar-

while the deep one

dense and

lies

in close

relation to the jaw, being only divided from the latter thin connective tissue of the

by the

mucous membrane.

1Z-

Âť>-^y'T

'-^^^^^^^wtm->f

Fig.

Section 1.

2. 3.

Through

,72.

a Part of a Dental Follicle.

(Cornevin

Lesbre.)

Crusta petrosa. External enamel. 4,

Internal enamel.

Dentine.

Odontoblasts.

Pulp.

The following changes which the gingival cushion undergoes constitute the process of tooth development: The first step in the direction of tooth formation

observed at about

ANIMAL DENTISTRY.

I'ic.

Perpendicular 1.

Epithelium of

tlie

Section gingival

33-

Tlirousli

Stalk for the future permanent tooth.

First dentinal formation.

4. 5.

Dental

Papilla.

cushion.

The jaw bone. The alveolar periosteum.

The crescent-shaped

ring rei)resents the enamel organ.

ANIMAL DENTISTRY. the eighth

when the deep cushion begins to grow inward

week

of the gingival

of foetal

stance of the jaw, which at that period cartilage.

The

upward around

celhilar layer

life,

into the sub-

represented by

same time grows

cartilaginous jaw at the

the descending epithelium until

presents

a deep trough-like groove which the gingival cushion

occupies. persists

The

through

now

outer or loose layer remains without and life

gums, while the deep or dense

as the

becomes better

layer pushes deeper and deeper into the jaw,

organized to form the

common enamel

germ.

The common

enamel germ which

no more than the deep

epithelial layer

of the

whole trough, but it

gingival cushion,

continued evenly through the tenth

at the ninth or

becomes tumefied

week

at regular intervals to

the enamel

stance between sniall

mound

mound and body

At the

devlop into larger bodies the

temporary tooth.

forces

The

upwards

month

Simultaneously the

into a

permanent body

dental papilla consists, therefore,

capped with epithelium.

of connective tissue,

third

sub-

cushion tumefies beneath

the gingival

(the dental papilla). of a

first

them gradually disappears, leaving only

for each

basement layer this

germs

form the

enamel germs).

real representatives of the future teeth (the

of foetal life

of foetal

life

the epithelial layer un-

dergoes petrification to form the future enamel organ.

The

connective tissue calcifies to form dentinal substance, while the base of the papilla remains unchanged to form the pulp.

While

this process

going on the papilla

suming the shape and form vision of a tooth to form.

gradually as-

of a tooth crown, the first di-

The neck and fang occur by

the

deposition of dentinal substance at the base of the papilla.

The aperture

into the pulp cavity

soon becomes narrow and takes

its

at first a

wide one, but

place at the end of the

fang as an apical foramen, the opening through which the vessels and nerves enter the tooth.

In the case of the molar

— ANLMAL DENTISTRY.

The

teeth several openings are formed, one for each root.

cement

three hard tissues to form.

teum

and

ossified connective tissue,

develops Ijetween the perios-

and the dental substance and

of the tooth cavity

influenced in

evolution through

its

the last of the

life

by both these

ele-

ments.

During these evolutionary changes each tooth

en-

closed within a separate sac ordinarily designated as a den-

During the same period the jaw

tal follicle.

great changes.

within

follicles

It is

growing upward

itself,

and

undergoing

to further enclose the

gradually separating them one

from another by the formation of bony partitions (the

inter-

dental cancellated tissue) until each tooth occupies a deep

compartirxnt

individual

tooth

completely at every stage of

fills

cavity its

and which entirely encloses both

istence

force of

takes

alveolar

the

its

expansion

forces

way

its

— which by

until

into the

place at the level of the dental arcade.

marks the beginning

the

evolution and ex-

sheer

mouth and This event

second period of dental evolu-

of the

tion.

The permanent teeth are developed much in manner. About the sixteenth week of foetal life neck becomes disconnected from the

and takes of the

its

place

on the

first

temporary tooth.

velopment, and

b}'

its

side,

the

same

a stalk or

common enamel germ

and secondly,

at the root

undergoes the same steps

of de-

upward growth absorbs the fang

the temporary tooth until only a

mere

The

shell remains.

permanent teeth that arc not represented by temporary predecessors are formed by the backward extension of the

common enamel

germ.

The

— the fourth

molar

— has

class

others which erupt later

some time

after birth.

first its

in life

permanent tooth

of this

origin in embryo, while the

may

not begin to form until

The enamel germ,

therefore,

not

entirelv a foetal structure, but exists until the last tooth

ANIMAL DENTISTRY. set

way toward

its

(Thus

maturity.

does not vary materially

49 far dental evolution

the different species).

^>^ EVOLUTION OF THE TEMPORARY TEETH. This period of dental evolution begins when the milk teeth

ends

make their when they In

successors. fore birth.

first

appearance on the buccal surface, and

are entirely replaced by their permanent

some animals the temporary teeth erupt be-

It is,

however,

few days after that the appears

all

at the

first

time of birth or within a

evidence of temporary dentition

domestic animals.

varies with each species.

The end

the period

In the horse the last temporary

Thus

teeth disappear at four and a half years of age.

the

period in the horse lasts from birth to four and a half years of age, in the

ox from birth

and

to four

a half years, in the

sheep from birth to three and a half years, birth to six months,

all

and

the

dog from

the pig from birth to three years.

the domestic animals except the

dog the temporary

incisors persist longer than the mo'ars.

THE HORSE. The

central incisors erupt before birth or, in

stances, within a few days after. teeth,

They

are

in-

white

large,

occupying the entire incisor arcade and contact their

The

opposing teeth by their anterior borders only. terior border

comes

some

still

pos-

hidden beneath the gums and only

to the level of the anterior l)order after three months'

wear, at which time they present the typical table of an

herbivorous incisor.

The cup

deep and

distinct,

and

in its

whole appearance cannot be readily recognized from that a

permanent

two

incisor.

At the

earliest period after eruption

influences are at w^ork for their destruction

nent tooth

crown

gradually encroaching upon

its

â&#x20AC;&#x201D;

-the

perma-

fang while the

becoming shorter and shorter under the influence

ANIMAL DENTISTRY.

50 of

wear

until at the

only a loosened

age of two and a half years there remains

shell.

LATERAL INCISORS. The

lateral incisors

make

their

appearance

from four

to six weeks, gain the level of the arcade at four

and are replaced by permanent incisors

months,

and

at three

a half

years.

CORNER The corner

INCISORS.

incisors appear on the buccal surface at about

Fig. 34.

Temporary A. B, C. D',

E, F.

Incisor Teeth of a Horse.

Labial surface of centra!, lateral and corner.

Lingual surface of same.

seven months, gain the level of the arcade at ten months

and are shed

at four

FIRST,

and

a half years.

SECOND AND THIRD MOLARS.

These teeth api)car about the time

of birth.

They

are

large organs and occupy the whole maxillary margin behind the interdental space.

At the time

of eruption their tables

arc covered with enamel, whicli soon wears off to expose

the dentinal tissue and cement. lost

by absorption from pressure

molars beneath.

The

first

Their fangs are g-radually of the growing-

and second are shed

permanent at

two and

one-half years and the third at three to three and a half,

leaving the molar arcades free from temporary teeth

ANIMAL DENTISTRY.

CANINES.

The

canine teeth are frequently referred to as being rep-

resented in youth by temporary predecessors.

The

cannot be accepted as entirely correct.

This claim

needle-like ca-

nines, occasionally observed in three-year-old colts,

must be

regarded as a freak of perverted dental evolution rather than as a part of the normal economy. t^il-i

sr"^'

'^•^•-r.

'-^S^

....J

Fig. 35-

Temporal"}' Incisors of the Colt. 3.

Inferior incisors at birth.

Inferior incisors at ten weeks.

Inferior incisors at four months.

Inferior incisors at seven

months.

THE Central Incisors*

— Erupt

one month and shed Lateral Incisors

OX.

at birth,

become prominent

one and a half years of age.

— Erupt

at birth, gain the level of the

arcade at one month and shed at two and a half years. *Lower jaw

only.

ANIMAL DENTISTRY.

Intermediate Incisors

— The

intermediates erupt at two

weeks, gain the level of the arcade at two months and shed at three

and

a half years.

Corner Incisors month, gain the

—The corners erupt

at three

weeks

to one

arcade at three months and shed

level of the

at four and a half years.

First,

Second and Third Molars

— As

in the horse,

these

Fig. 36.

Tompornry Molar

molars erupt

at birth.

years, the second at

1"lic

Tectli

hrst

two and

Horse.

cast off at one

a half

and

a half

years and the third

three and a half years.

THE Central Incisors

shed

— F.rupt

at three years.

PIG.

at three to four

months and

'are

Fic. 37.

Superior and Inferior [Molar Arcades of the ^Months.

A, B.

Opening

fur the 4th Molar.

Horse under the Age of lo

ANIMAL DKN'riSTKY.

Lateral Incisors

—

at four niontlis

l'".ni])t

and arc shed

tlircc }-cars.

Corner Incisors

— l^-upt

and are shed

birth

six

months.

Canines

— Erupt

temporary canines

First

Molar

common

of the pi": are

more prominent

are

and are shed

at l)irth

the

— Tlic

one year

(The

to both sexes, l)ut

n.iale).

molar

tirst

of the hoi;- has

no temporary

predecessor.

Second and Third Molars at

two

— Irrupt

birth

and are shed

\-ears.

Fourth Molar

— Erupts

at six

months and

sh.ed at

two

years.

THE DOG. Central Incisors

—

I'^rui)t

four weeks and are shed at

four montlis.

— Erupt

at four

— Erupt

Lateral Incisors for.r

weeks and are shed

months.

Corner Incisors

four weeks and are shed at

months.

five (

The

incisor teeth

other until the

Canines

—

do not come

ag-e of lifteen

Eru]")t at

contact witli one an-

months).

four weeks and are shed at six months.

The}' are commcin to botli sexes. First

Molar

— There

no temporary

first

molar

the

dog.

Second, third and fourth molars erupt

and shed six

at six nu^nths.

at five to six

weeks

fourth ma\- be delayed until

and one-half to seven months.

At the age the

The

dog

of se\'en

months the

entirely re])laced by

its

tem])orar\- denture

])ermanent successor.

(jf

Fig. 38.

Superior Denture of a 2- Year-old Hog. 55

(Cornevin

Lesbre.)

ANIMAL DENTISTRY.

THE SHEEP. Central Incisors

and arc shed

— Erupt

(lurino- ilic

I'lrst

month

after birth

at fifteen to eit^htecn montlis.

Lateral Incisors

— Erupt

(hirino- the

first

month,

few

(hiys after the eentrals.

months.

and are shed

twenty to twenty-four

ANIMAL DENTISTRY. Intermediate Incisors

— Erupt

during the second to the

fourth week, a few days after the laterals, and are shed at

twenty-four to thirty-three months.

Corner Incisors and are shed

— Erupt

about the

at four to four

fifth

week

after birth

and a half years.

t H

First at

Molar

— Erupts

first

month and

shed

first

molar and

shed

one and a half years.

Second Molar at

during the

two and

— Erupts

with the

a half years.

Third Molar

— Erupts

with the

shed at three and a half years.

first

and second and

â&#x20AC;&#x201D; ANIMAL DENTISTRY.

EVOLUTION OF THE PERMANENT TEETH. The

pennaiient

clc\cl()i)Hient of the

s^ins diirins;'

the foetal

resented only

animals be-

Dnring- this period they are rep-

life.

a stalk or

1)}'

teetli

neck extending- from the enamel

o-erm of their temporary analogues, located

first

on the side

Fig. 41.

Mnhir Denture A.

Infcri^^

P>.

Superior 4th molar.

4tli

and afterwards

Birth.

irolar.

the root.

the central incisors and the

At the time of birth the germ of first,

second and third molars

are alreadx- ])rominently formed at the root of the temporary teeth,

and the fourth molar

develop

â&#x20AC;&#x201D; consists

of a

enamel germ located molar.

(Fig".

the hrst ]H'rn\'inent tootli to

roimded hy];ertrophy just posterior to

41 A. B.)

of the

common

the third temporary

The temporary molars occupy

the

ANIMAL DENTISTRY. entire

jaw behind the interdental space

months.

same

molar occupies

mature animal.

their

until the

age of ten

In the herbivora the fourth molar forces

to the surface in the

always

filled

in the

way

relative position that the sixth

with molars, the fourth,

way behind

its

The jaw fifth

therefore

and sixth forcing

their successive neighbors.

Fig. 42.

Molars of

During the

first

Horse Approaching

The

Months.

year the only prominent visible event

the evolution of the permanent teeth

fourth molar.

5 to 6

the eruption of the

invisible events occurring in the

germs

located at the roots of the temporary are, however, of no less

importance.

They

normal shape and

size,

are developing rapidly into teeth of

gradually transgressing upon and

shortening by absorption the fangs of the temporary teeth,

ANIMAL DENTISTRY

molars and incisors

The

alike.

first,

second and third mo-

lars make the most rapid prog-ress during the

paratory to their subse(|uent eruption

one

first

year, pre-

two years

The incisors are less developed, the centrals are somewhat prominent preparatory to their eruption two years

hence.

hence, but the lateral, intermediates

corners o-erm.

are

Such

—

ruminants

—and the

merely represented by an undeveloped tooth is

the condition of development of the denture

Fig. 43.

Molars of a Horse Approaching 10 Months.

of an herbivorous animal at the age of one year

from whence

(See Fig. 43.)

the evolution proper begins.

THE HORSE. Central Incisor

— Begins

to develop in

the shape of a tooth during the of the alveolar shell at

mal

first

embryo, assumes

year, reaches the level

border at two years, expels the temporary

two and

a half years

and takes

its

place at the nor-

level of the arcade at three years of age.

Lateral Incisor

— Begins

to develop during the first six

ANIMAL DENTISTRY.

months, assumes the shape of a tooth during the second year, reaches the alveolar border at three years, expels the tem-

porary

and a

shell at three

half years

and takes

its

place at

the level of the arcade at four years.

Corner Incisor to develop at

â&#x20AC;&#x201D;

two

very rudimentary at one year, begins

years,

assumes the shape

of a tooth at

three years, reaches the alveolar border at four years, expels the temporary shell at four and a half years and takes

Fig.

Molars of

its

44.

Horse Approaching the Age of

Years.

place at the level of the arcade at five to five and a half years.

Canines years, but

â&#x20AC;&#x201D; Erupt may

be delayed

hardness of the jaw. of the superiors,

First,

foetal

life

in their

outward course by the

Occasionally their growth, especially

arrested beneath the

enth year of the animal's erupt slightly in

age of four to four and a half

at the

life.

The

gums

until the sev-

inferior canines

always

advance of the superior.

second and third molars begin to develop of the colt.

in the

birth they are small, rudimentary

ANIMAL DENTISTRY.

objects, but

become

tooth-like very rapidly during the

twelve months, at which time they are

and anatomically

growth

about equal, each growing to the

At two and

alveolar border.

ond expel the temporary

a half years the first

two and

its

a half

growth as

maxilla.)

1)locked in

one and

two and

tw^o to

now been

The

ac-

third

molar

in active serv-

(See osteoma of the

a half years old the develop-

at a standstill, until the

when

age of

finally expels its shell

and then grows tardily outward to the It

sec-

outward course by the

its

a half years.

three to three and a half years,

and

years seems to be mysteriously retarded if

of the third

the

and become concerned

shell

unyielding fourth molar, which has ice for the past

their

level

mastication at about three years of age.

tively in

ment

all

During the ensuing year

similar.

first

morphologically

level of the arcade.

not unusual to find this molar below the level of

neighbors at four and even

Fourth Molar

â&#x20AC;&#x201D;The

of the horse's teeth.

months mass

of foetal

years old.

fourth molar

Its

the most interesting

development begins during the

life.

five

birth

its

last

rounded

consists of a small,

rudimentary tooth substance, developing from a

backward projection

of the

common enamel

germ, and

lo-

cated in close contiguity to the fang of the third temporary

During the

molar.

first

ten

months

after birth

grows

very rapidly into a shapely tooth and points to the surface at

about the end of the tenth month.

already actively concerned

At twelve months

mastication, although

morphologically defective, assuming

its

maximum

stability

only during the next two years. Fifth six

Molar

â&#x20AC;&#x201D; The

common enamel germ

at the

age of

months, after having formed the fourth molar projects

At one year old the

backward

to form the

mation

almost perfect, at one and a half years

fifth

molar.

for-

erupts.

Animal dentistry and

two and

a half years

found on a

63 level

with the

fourth.

Sixth Molar to erupt, five

â&#x20AC;&#x201D; The

sixth

molar

which event occurs

years of age.

Its

the last of the molars

any time between four and

formation, like that of the other per-

manent molars, having no temporary predecessors, depends upon the backward growth of the common enamel germ.

The

first

evidence of this molar

Fig.

of the fourth

yielding and

and its

form

eruption

10 Months.

rounded mass similar to that

of a

fifth.

seen at two to two and

45.

Molar Denture of the a half years in the

this

may

age the jaw

more un-

be delayed by the resistance

offered therefrom.

RUMINANTS. Central Incisor

â&#x20AC;&#x201D; Reaches

the alveolar margin

year and erupts at one and a half years.

one

ANIMAL DENTISTRY.

Lateral Incisor

— Reaches

the alveolar margin

two

years and erupts at two and a half years.

Intermediate Incisor

— Reaches

the alveolar margin

three years and erupts at three and a half years.

Corner Incisor

— Reaches

the alveolar margin

years and erupts at four and a half to First

Molar

— Reaches

four

five years.

the alveolar margin at one year,

expels the temporary shell at one and a half years and be-

comes concerned

Second Molar

mastication soon after.

— Reaches

the

two and

years, expels the temporary shell at

and gains the

level of the first

Third Molar

— Reaches

cerned

Molar

the table level

— Erupts

two

shell at three

later.

and a

about four years.

level at

at nine

months and becomes con-

two and

several months

Sixth Molar vears.

a half years

mastication at ten to eleven months.

Fifth

— Erupts

month

temporary

and gains the table

Fourth Molar

molar

two

the level of the alveolar margin

at three years, expels the

half years

margin

alveolar

— Erupts

a half years

between the ages

of four

outward progress

in the horse, its

and gains

later.

and

five

hindered by

the hardness of the jaws at that age.

CARNIVORA.

— Erupts Lateral Incisor— Erupts Corner Incisor— Erupts to Canines— Erupt

at three to four

Central Incisor

at three to four

at five to live

five

six

months.

and

months,

a half

months.

common

to both

sexes.

First

Molar

— Erupts

at three

months, and has no tem-

])orary predecessor.

— Eruj^ts — Erupts Fourth Molar— Erupts Fifth Molar — Erupts at

Second Molar Third Molar

months.

at five to six

months.

at five to six

months.

four to five months.

—— ANIMAL DENTISTRY.

— Erupts at Molar — Erupts

Sixth Molar

Seventh

five to six

65-

months.

seven months.

OMNIVORA.

— Erupts at two and a half years. — Erupts at three years. Corner Incisor — Erupts at six months. Canine — Erupts at one year and common to both sexes. a permanent tooth. First Molar — Erupts birth and Second Molar — Erupts at two years. Third Molar— Erupts at two to two and a half years Central Incisor

Lateral Incisor

Fourth Molar Fifth

Molar

Erupts at six months. Erupts at one year.

— Erupts Seventh Molar — Erupts Sixth Molar

one and

a half to

two

years.

at three years.

NUMBER OF PERMANENT TEETH. Incisors.

Canines.

Molars.

Total.

Horse

Mare

T^2

Pig

Dog

Cat

Rabbit

NUMBER OF TEMPORARY TEETH. Incisors.

Canines.

Molars.

Total.

Pig

Dog

Cat

4 o

Horse

Rabbit

ANIMAL

DP:NTIS'rRV.

FORMULAE OF THE TEMPORARY AND PERMANENT DENTURES OF DOMESTIC ANIMALS.

ANIMAL DENTISTRY.

CHAPTER

III.

RETROGRESSION OF THE TEMPORARY TEETH. The temporary

teeth attain their greatest capacity and

length at the time of eruption, after which event they at once

begin to retrogress under the influences of pressure absorption at the root and of wear from mastication at the ta1)le

extremity, until only a shell remains to be expelled

into the

The

mouth.

ding) occurs to the half years,

and the

half years,

after

from temporary porary teeth

first

and second molars

last to the

which time the denture

The order

teeth.

two and

corner incisors at four and a

and a half years, the

and the central

entirely free

of shedding of the tem-

and second molars

first

incisors.

Three to three and a

(2)

event of this character (shed-

in solipeds is as follows:

Two

(i)

first

half years, the third molars and

the lateral incisors.

Four and a

(3)

This order

be made to apply to

all

ruminants and

In the carnivora the destruction of the temporary

solipeds.

denture

may

half years, the corner incisors.

remarkably rapid, as

at the

age of seven months

no temporary teeth remain.

RETROGRESSION OF THE PERMANENT TEETH. The

retrogression of the permanent teeth

portant feature of dentistry of animals.

and eventual destruction and ruminants attain

of the teeth.

their

maximum

the second year after eruption.

The

the most im-

includes the

wear

teeth of solipeds

length and volume

During the

first

year they

ANIMAL DENTISTRY. g-ain

in length

and volume by expansion

lose slightly by wear.

wear during the

first

of the fang,

but

The growth, however, exceeds

the

year.

During the second year the wear

and growth are about equal. teeth

The

greatest length of the

therefore attained during the second twelve

of their existence within the mouth.

months

During the succeed-

FlG. 46.

The Destruction A. B.

Temporary Permanent

of a

Temporary Tooth by

the Permanent.

shell.

tooth.

ing years the teeth do not grow,- but instead undergo a

gradual and regular process of destruction under two fluences (i)

in-

Wear from

mastication, which slowly shortens th^

length of the tooth. (2)

Receding

of the alveolar margin,

which gradually

shortens the depth of the alveolar cavity. In the herbivorous animals both of these influences are

ANIMAL DENTISTRY.

70 at

work

to a remarkable degree, while in the carnivora

omnivora only the second influence

concerned

and

the de-

In the herbivora the length of the teeth

structive process.

varies from the

long-,

subject, to the

short,

three or four-inch tooth of the half-inch

young

tooth of extreme old age

(from the wear of mastication), while the alveolar cavity varies from the exceedingly deep excavation of youth to

The diminution

the shallow, flattened cavity of old age. the depth of the alveolar cavity occurs in is

the animals, and

all

solely responsible for senile self-extraction in the animals

having simple teeth. In the animals having simple teeth the table retains

its

enamel covering through

does not diminish

Wear from

minant and soliped

The enamel

first

and the tooth

length from wear.

mastication.

â&#x20AC;&#x201D; When

the teeth of the ru-

enter into the process of mastica-

tion they are covered with face.

life,

enamel over the grinding sur-

addition dips deeply into the

the tooth around the infundibula.

As soon

wear begins

the surface enamel of the table at once wears

body

off,

exposing

the dentine and leaving only the edges of the enamel organ

on the grinding surface.

The

dentine, ordinarily a sensitive

substance, becomes hard and insensitive

along the table

surface, by the deposit of dentinal cells within

The

tubules.

area of insensitiveness extends throughout the entire

table and to the depth of one to first

its

year of wear, but

two millimeters during the

the subsequent three or four years

descends to the depth of one centimeter or even more.

the age

of ten to twelve years

has descended to more than

one-third of the entire tooth in the molars, and to the depth of

about two centimeters

has passed the age of eighteen the tooth

organ

When

the incisors. is

the animal

practically a dead

so far as the sensibility of the dentine

concerned.

That the stimulus to the proliferation of dentinal cells (osteo-dentine) is wear is demonstrated in the fact that teeth

ANIMAL DENTISTRY. that do not contact opposing teeth (e.

71 g.,

brachygnathism)

are sensitive to the very tips.

During youth and through the prime

life

the active

tooth wears at the rate of about two milHmeters each year. In the asred animal the loss

slower.

In the case of the

^30yrs. Fig. 47.

Change in Sliape of the Incisor Tahles Wear, from 6 Years to 30 Years.

Illustration of the

visible teeth

(the incisors) the

of the table a constantly

wear brings

as a Result of

to the surface

changing picture, by exposing to

view the different consecutive parts

of the tooth,

from the

flattened table of youth to the triangular table of old age.

The most

striking change in the teeth from

wear occurs

AXLMAI. DENTISTRY.

to the incisor teeth, especially

tlie

the best evidence of the a^^e after the

chanq-es

the

infnn(hl)n]uni

which furnish

inferiors,

year.

fifth

and then by change

The infundibuhim

shape of the table surface.

First, in

tlie

of the tooth

produced by the infolding of the enamel into the body of

two and

the tooth to a depth of one and a half to

centimeters.

The bottom

with crusta petrosa,

the outer end

Init

formed

of the cavity thus is

a half is filled

empty and

consti-

which becomes blackened by the chemical

tutes the cup.

action of foods and saliva.

The

infundibula of the incisors

are shaped like a flattened cone with the apex inward and

When

the elliptical opening outward. virgin, the cup,

the tooth

made more apparent by

but a

dark color, pre-

its

sents an elliptical opening at the table surface, but as the

crown

w^ears aw^ay

becomes shorter and more rounded

and disappears entirely when the crown has worn as as the crusta petrosa that

fills

far

the bottom of the infundibula.

Thereafter the infundibula are not dark but are recognized

their surrounding enamel, at first

becoming small

circular rings located well

posterior border of the the cup

still elliptical,

tal)les.

must not be mistaken

but

final-

toward the

Tn the study of dental wear for the infundibuhim, as

refers only to the unfilled portion of the infun(lil)ulum.

"cup"

The

cups of the incisor teeth disappear three years after eruption,

and the infundibuhim about ten years

to fifteen years

after.

The molar into the fang.

teeth have

They

two infundibula extending deeply

are entirely

filled

and would entirely escape notice but

with crusta petrosa for the

presence of

a small dark spot in the center.

In shape the tables infundibula.

In the

change even more than

young tooth

the table

come

to the surface.

fiattened

their

from

away the other The table becomes

before backw^ard, but as the crowns wear parts of the tooth

ANIMAL DENTISTRY.

triangular, then round and finally in

first

tened from side to

The

side.

extreme age

triangular shape

pearance almost as soon as the cups disappear

and

incisors,

lateral

makes

flat-

ap-

its

in the central

while the corners maintain their ob-

long shape until after the age of twelve, and even never

become

as distinctly triangular as the former.

Receding of the alveolar margin

in the

herbivora than

more prominent

other species, although

feature of dental retrogression

stitutes a

Through

in the

(See Fig. 47.)

all

con-

animals.

influence the teeth lose their implantation

its

gradual stages until

extreme old age they are held

by the gums and small

pits in the jaw,

which

In the incisor arcades the alveolar margin recedes

much

position only

retain the remaining roots.

faster than the teeth

wear

at the table,

results in the elongation of the

comes

older.

rare

crowns become shorter only

when

crowns

the

of the

ceding jaw,

teeth

A\'ith

the

age, but this incident results

of old

grow in length and young horses. in

occurs and

The long

cpiality.

horses due to the re-

responsible for the general impression that

The receding process change

reverse

defective in

are

incisor teeth

the teeth

than

crowns as the animal be-

the

cases

which circumstance

that they are longer in old

also responsible for the gradual

the inclination (angle) of the incisor teeth.

The

angle formed by the incisor teeth at the contact point

obtuse

one

the young, but changes gradually into a very acute

the aged animal.

This change

the result of the

great curvature in the incisor tooth, which

animal

the

implanted into a deep curved cavity.

young As the

tooth wears the part projecting forwards becomes exposed

and the increased inclination all

results.

The

teeth of herbivora, are longest in the

incisor teeth, like

young animal, but

ANIMAL DENTISTRY.

have a longer exposed portion (crown)

owing

in the

aged subject,

to the receding of the alveolar margin.

A SUMMARY OF DENTAL EVOLUTION AND RETROGRESSION APPLIED TO THE DETERMINATION OF AGE. The age

of the horse

of the incisor teeth,

and

determined by the examination

in certain

instances

tlic

molars, as

follows

From

(i)

birth to one year by the evolution of the

temporary

incisors.

From one year

(2)

two and

a half years by the

eruption of the fourth and

fifth

molars and

the evolution of the temporar}- incisors.

From two and

(3)

one-half years to five years by

the retrogression of the temporary incisors, the evolution of the canines and the evolution of the sixth molar.

From

(4)

five

and a

retrogression

half years to nine years

the

by the

infundibula of the in-

ferior incisors.

From

(5)

(i)

nine years to old age by:

Changes

the shape of the tables of the in-

ferior incisors.

(2)

Changes

(3)

Changes

the anterior face of the superior

incisor arcades. in the inclination of the incisor ar-

cades.

crown

(4)

Changes

the

(5)

Changes

the molars.

of the canines.

FROM BIRTH TO ONE YEAR. The

colt at birth, or within a

incisor teeth

â&#x20AC;&#x201D; the

day or two

after,

has four

superior and inferior nippers, and three

Animal dentistry. molars

crowns

of the

each arcade, the

The

second, and third.

short and contact only at the

incisors are

anterior margin.

first

infundibula are wide, elliptical and

deep, and their posterior boundaries are buried within the

At one month the posterior edges

gums.

of the infundibula

are exposed and the lateral incisors are breaking through

Two

the gums.

weeks

crowns answer the same

later their

During the next eight

description as the centrals at birth. or nine

months there

no great change

in the

arcades ex-

cept the elongation of the crowns, which resemble a cone

broken

off at its apex.

The

month

tenth

marked by the

1: \

Fig. 47a. Inferior Incisors at Birth.

eruption of the corner incisors and the fourth permanent molars.

FROM ONE TO TWO AND A HALF YEARS. The absence of any prominent event during this period makes the determination of age rather ditTicult. The incisor teeth become large and prominent in all the features of teeth, If

and are not

easily recognized

from permanent

unassisted by the colt-appearance of the subject the

during the

last part of this

period

teeth.

mouth

readily mistaken for a

When

full

mouth

ists

the examination of the molars will reveal the presence

permanent

but four teeth

and

half years

through the gums.

incisors.

each arcade.

the

fifth

The

At the age

molar

will

any doubt ex-

two

be found breaking

incisors are white,

have a some-

t(^

ANLMAL DKXTISTRV

Figs. 48

Anterior View of Incisors

llie

('{"able

and

Incisor

View)

49.

Denture at

Months.

ANIMAL DENTISTRY

Fig. 50.

Incisor Denture at

Months (Table View).

ANIMAL DENTISTRY.

Fig. 51.

Incisor Denture of a Colt at

t8 ]\Tonths

(Tabic- View").

ANIMAL DENTISTKY

Fig. 52.

Incisor Denture at 2 Years

(Table View).

ANIMAL

what

DENTIS'I^KV.

neck and are separated with ^unis shaped as

proiiiiiK'iil

an inverted cone.

'J'lie

crowns do not contact one another

throughout their entire length, as half to six years old, for

assist in

The absence of canines making the differentiation.

likely to

occur

mistaken.

in the

the horse five and a

which the two-year-old might be (in the

male)

will also

The confusion

most

examination of a thoroughbred or

trot-

ter with a well developed muscular system, and the habits of

an older horse from training.

FROM TWO AND A HALF TO FIVE YEARS. The determination

age during

this

period

simple and more certain than at any other period of the horse's

owing

life,

At two and

occurring during this period. central

a half years the

temporary incisors are readily recognized

loose preparatory to shedding. cast of짜

prominent events

to the three successive

At three years

being

1)y

old they are

and the permanent successors, broad and shiny, are

seen protruding beneath, leaving an interrupted surface in the arcade.

three and a half to four years the laterals

y\t

undergo the same transformation, and five,

The

the corners.

at four

mouth

five-year-old

and a

half to

recognized by

the deep, oblong infundibula of the centrals and laterals

and the imdeveloped condition are bluish-white, have a short

The

opponents.

of the corners.

The

latter

crown and do not contact

posterior edge of the table

within the gums.

The

still

canines are already visible

their

Iniricd in

both

the jaws, but especially in the inferior, and the molar arcades

are completed.

ond molars molar casts

cast ofT the

full

mouth

temporary

permanent

teeth.

first

and sec-

shells, at three the third

and

molar erupts, leaving of

years the

a half

off its predecessor,

half the sixth

At two and

at four to

at the

end of

four and a this period

ANIMAL DENTISTRY.

Fig. 53.

Incisor Denture Approaching 2j^ Years

(Table View).

ANIMAL DENTISTRY.

Fig. 54.

\ncisor Denture at

25/2

Years

(Table View).

ANIMAL DENTISTRY.

Fig. 55-

Incisor Denture

at 3

Years (Table View).

ANIMAL DEXTISTRV.

Fig. 56.

^ncisor

Denture

Years (Anterior View).

ANIMAL DENTISTRY.

Fig. 57.

Incisor Denture at

3;/.

Years (Table View).

£5

AMIMAL DENTISTRY.

Fic. 58.

Incisor Denture at 4 Years (Table View).

ANIMAL DENTISTRY.

Fig. 59.

Incisor Denture at 4 Years

(Anterior View).

ANIMAL DENTISTRY.

Fig. 6o.

Incisor and Canine Dentures at 41I Years (Table View).

ANIMAL DENTISTRY.

FROM FIVE TO EIGHT YEARS. The age during

this period

determined by changes

the infundibula of the inferior incisors, the cups of which

disappear

regular succession, beginning with the centrals.

some instances

small round spot remains for several

years in the center of the infundibulum, but this event must

The

be regarded as equivalent to the disappearance.

pearance of the blackened cup

six years old the central

lateral cup.

and

bottom

one has become shallow

of the corner inferior incisor

persistent than that of the centrals

remain quite prominent even years. ly

Its

change

of the infundibulum.

cup disappears, at seven the

at eight the corner

The cup

and rounded.

marked by the appearance

of the crusta petrosa filling the

disap-

at the

shape from

and

laterals,

and may

age of ten to eleven

elliptical to

round

equal-

valuable in the determination of the age at that period.

FROM NINE YEARS TO OLD

AGE.

After the age of nine years the retrogressive changes

continue incessantly, but without any prominent event to

mark

The age

the exact age.

of the horse

henceforth

only estimated.

Nine years

â&#x20AC;&#x201D; The

by the appearance val

margin

age of nine years

of the crusta petrosa

easily

groove

determined

at the gingi-

the superior corner incisor and the

downward curvature

of the

gums

at that point.

The

slight

infun-

dibula of the inferior incisors are nearer to the posterior bor-

der of the taldes triangular.

The

the

inferior

centrals,

which are now quite

corner incisors are

present a rounded black cup and are beginning to first

oblong,

still

show

sign of increased inclination of the incisor arcades.

anterior surfaces of the teeth are

becoming yellow.

the

The

ANIMAL

DEXTIS'I'RV

Fic. 6i.

Incisor Denture

Arprnaching

Years (Table View).

ANIMAL DENTISTRY.

Fig. 62.

Incisor Denture at 5 Years

(Table View),

ANIMAL DENTISTRY.

P^IG.

63.

Incisor Denture at Sl< Years (Tahlc View).

ANIMAL DENTISTRY.

Fig. 64.

Incisor Denture at 6 Years (Table View).

l)E X Tl STR Y

"^-â&#x20AC;˘^'**aMtHili'!'ii|i;i|;i;i;!ll:i|i!lj

Fjg. 65.

Incisor Denture at 6 Years

(Anterior View).

ANIMAL DENTISTRY.

Fig.

Incisor Denture at 6 Years

65.'\.

(Lateral View), with clination

Dark Lines Showing

In-

ANIMAL DENTISTRY

Fig. 66.

Incisor Denture at

6j/'

Years (Table View).

ANIMAL DENTISTRY.

Fig. 66a. Incisor Denture of a

Mare

Years (Table View)

ANIMAL DENTISTRY.

Fig. 67.

Incisor Denture at 7 Years

Table View).

ANIMAL DENTISTRY.

Fig. 68.

Incisor

Denture

7 Years,

Dark Lines Showing

Inclination.

100

ANIMAL DENTISTRY.

Fig. 69.

Incisor Denture of a

Mare

at 7

Years

(Table View).

ANIMAL DENTISTRY.

Fig. 70.

Incisor Denture at 8 Years

(Table View).

101

102

Fir,.

71.

Incisor and Canine Dentures at 9 Years (Table View).

ANIMAL DENTISTRY.

103

Fig. 72.

Incisor Denture at 9 Years, with

Dark Lines Showing the

Inclination.

104

ANIMAL DENTISTRY.

Fi.;.

Incisor Denture of a

Mare

73.

9 Years

(Table View).

— ANIMAL DENTISTRY.

Ten

to twelve years

are

—The

105

and

inferior centrals

laterals

triangular, the cups of the inferior corners are

disappearing entirely, the enamel around the infundibula of the centrals

and

laterals

changing from oblong to round,

the crusta petrosa groove on the superior corners to three millimeters long

and centrals, and superior incisors

and

two

appearing on the laterals

length of the crowns of the

finally the

The crowns

markedly increased.

of the

canines are large and are becoming rounded at the gingival

The

margin.

marked feature

inclination of the incisor arcades

mouth and

of the

— The

the superior corner incisor

now

recognized by a mere

glance at the lateral aspect of the arcades.

Thirteen to fifteen years

(Figs. 74, 75, y6.)

crusta petrosa groove on

nearing the middle of the

crown, the tables are markedly triangular, the crowns of the superior incisors are becoming widely separated from

the gums, and are l)ecoming narrow near the gingival margin, the infundibula

cisors are

island

now

and

of the central

but small circles

— projecting above the

lateral inferior in-

the enamel

enamel

and located

level of the dentine

well toward the posterior aspect of the table, and the gingi-

margin

val

of the superior central incisors

than that of the

round

laterals.

at the gingival

margin

Sixteen to twenty years arcades ject

The crowns

so pronounced

of the canines are

(Fig. yy.)

—The that

inclination of the incisor

the

forward almost on a straight

superior corner incisor

much lower

inferior line

incisors

grooved almost to the contact

border, the crusta petrosa grooves extend well

over the crowns of trals

either

all

pro-

with the jaw, the

the incisors, the

shorter than that of the

crown

downward of the cen-

laterals, the infundibula

disappeared entirely or exist only

the

have

form of

small projections of enamel near the posterior border of the tables of the inferior incisors, the

crowns

of all the superior

106

ANIMAL DENTISTRY.

Fig. 74.

Incisor and Canine Dentures at 10 Years (Table View).

ANIMAL DENTISTRY.

Fig. 75.

Incisor Denture at 12 Years

(Table View).

107

108

ANIMAT. DENTISTRY

Fk;.

Incisor Denture

Between the Ages of

'jCx

and u, Inclusive,

Showini'- the Inclination.

wilii

Dark Lines

ANIlvrAL

DENTISTRY.

Fig. ^7.

Incisor and Canine Dentures at 13 and 15 Years (Table View).

109

ANIMAL DENTISTRY.

Fig. 7ÂŤ.

Incisor and Canine Dentures at i6 to 20 Years (Table View).

ANIMAL DENTISTRY.

Fig. 78a. Incisor Denture of a

Mare from

16 to 20

Years (Table View),

Ill

ANIMAL DKNTISTRV

Fig. 79.

Incisor Denture

-at

16 to

20 Years, with Dark Line Showing Average chnatinn.

In-

— ANIMAL DENTISTRY. incisors,

with the possible exception of the corners, are long

and completely conceal the terior

II3

view when the mouth

from an an-

incisors

inferior

closed, the contact edge of

the superior incisor arcade overlaps that of the inferior, and finally the tables of the central inferior incisors are

circular

and even flattened from

Twenty

(Figs. 78, 79.)

side to side.

to twenty-five years

— The

becoming

mouth presents

all

the features of the foregoing paragraph with the exception that the enamel island, representing the last vestige of the

infundibulum, has entirely disappeared and either a light or dark spot

-the dental star

The

sents the obliterated pulp cavity.

the external enamel around face of the dentine

v\'ithin,

at the gingival end.

Old age

— The mouth

replaced by

—which

repre-

tables are round

them projects beyond the and the crowns

incisors are widely separated with

row

and sur-

of the superior

gums and

are very nar-

may

present either

(Fig. 79.) of

an old horse

very long or very short (worn out) incisor teeth.

long,

the implantation can be disturbed on manipulation and can

almost be extracted wnth the fingers. at the tables are separated

If short,

the crowns

one from another by the gums,

the crowns are round and the tables of the inferior centrals

The

are flattened from side to side.

canines are round and

the molars are uneven, easily extracted, and their roots can

felt

along the gingival margin.

Often a number of molars

are absent from self-extraction.

ROUTINE OF THE EXAMINATION OF A HORSE'S MOUTH TO DETERMINE THE AGE. I.

The horse

approached on the

are opened laterally, the

left

side

and the

hand elevating the upper

lips

lip

the right depresses the under one, thus exposing the lateral

aspect of the incisor arcades.

glance at the inclination

.14

ANIMAL DENTISTRY.

Fi<;.

Incisor a:ul Canine Dentures at

79.\. _'0

lo 25

Years (Table View),

ANIMAL DENTISTRY,

115

Fig. So.

Incisor Denture of an

Old Horse, with Dark Lines Showing the IncHnation.

ANIMAL

116 will

)i:

XT IS TRY

determine whclher the horse

second glance

teeth are

old or young.

young

taken to determine whether the exposed

permanent or temporary.

Fu;. Si.

Anterior View of the Incisor Denture of an Extremely Old Horse. 2.

Without releasing the hold the inspector steps

the front of the horse, elevates the upper

hand and

slips the

lip

with the

to left

second and third finger of the right into

ANIMAL DENTISTRY. the interdental space, the

tirst

117

expose the superior ar-

cade and the latter to cause the horse to open the mouth

From

slightly.

position the length, color, crusta pe-

this

trosa grooves, contiguity of the crowns, and the gingival

margin

of the superior arcade

inspected.

are

Without changing positions the

left

hand

now

placed gently into the interdental space as the right one

depresses the lower

lip

expose the tables of the incisor

teeth to determine the shape of the tables, the absence, existence or size of the cups,

and the shape

of the internal

enamel surrounding the infundibula.

the

deemed necessary, without changing the is slipped upward along the left molar

hand

left

to determine the

number and condition

position

arcades,

molar

of the

teeth.

ANOMALIES OF THE TEETH, NATURAL AND ARTIFICIAL. Nature's anomalies

common

are of such

This

will

frequently mislead the diagnos-

especially the case

when one

two features

growth and wear are depended upon.

of dental

mon

evolution and retrogression

occurrence that any set rules for the

determination of age tician.

in dental

The com-

anomalies of the teeth are

(i)

Anomalies

of eruption.

(2)

Anomalies

of the texture of the dental tissues.

(3)

Anomalies

of the infundibula.

(4)

Anomalies of the cups

(5)

Anomalies due

of the infundibula.

to the character of the food.

Eruption of the teeth

will

vary

slightly

ferent breeds and from climate and artificial influences.

dif-

the well-bred horse, the thoroughbred, hackneys and Ameri-

can trotters,

which the development

forced from colt-

hood, the temporary teeth erupt several months earlier than in the

horse reared under more natural conditions, and the

ANIMAL

118

same precocity

will

DKX'I'ISTRV.

he observed

the sheddini;- of the tem-

porary teeth, from the increased amount of hard food gested at an age

when

the teeth are

still

In the one-year-old race horse that

ture.

development

fed to force the

of the

in-

defective in texis

trained and

muscular system the

teeth will share in the development providing the unnatural

requirement does not impair the general health. (2)

The same

of the

texture of the teeth varies

in difTerent

animals

under the same conditions, from

class reared

causes too obscure to recognize.

Deficiency in the inorganic

proximate principles of food

certain districts has been

observed to yield horses with

soft teeth.

The

variation in

the texture of the teeth will either hasten or retard the

retrogression of the teeth.

events by which age

AMicn the teeth arc hard the

determined

be retarded, and as

will

a consequence the animal will appear young.

When

the

teeth are soft the reverse occurs and the animal appears

The anomalies caused by

older.

the varied density of the

tooth substance are precocious or retarded changes cups, infundibula, shape of

crowns. is

One

of the

the

tables

most pronounced

and length

the

of the

results of soft teeth

the shortening instead of elongation of the incisor crowns

becomes

as the animal (3)

The

old.

incisor teeth may vary They may be very shallow in

infundibula of the

greatly as to their depth.

some animals and very deep in others, and thus prove misleading when depended upon alone in the determination of age. (4)

The cups

of the infundibula are equally subject to

variations, due to the

tom

amount

of the infundibula.

almost small

full

of crusta

amount.

when empty

When

of crusta petrosa in the bot-

some

teeth the infundibula are

petrosa, while others contain but a full

the cup disappears early, and

persists longer.

This anomaly

not con-

ANIMAL DENTISTRY. fusing

the shape of the infundibula

(5)

Character of the food

taken into account.

hasten or retard the wear

will

remarkable degree.

of the teeth to a

119

Grazing, which re-

quires the use of the incisor teeth to detach the food, has a

Fig. 81B.

Fig. 81A.

Bishoping

Gouge.

Drills.

precocious influence, while stable feeding, which exacts but little

work from

Artificial

the incisors, retards the wear.

anomalies refer to alterations

of the incisor teeth

from the normal (i)

by the use

may

result

in the

appearance

of instruments.

Deviation

from

Shortening of the crowns of the

incisors, espe-

AXIMAL DENTISTRY.

120

cially the superior,

with the incisor nipper and

file.

I'ohshing the anterior surface of the superior

(2)

incisors.

(3) 1.

Renewal

of the

cups by drilling and staining.

Shortening of the crowns of the superior incisors

will

The

ar-

deceive only the novice or the careless expert. tificially

shortened crown

promptly recognized by the

in-

terrupted contact of the anterior margin of the arcades, not by the other retrogressive changes which cannot be faced.

ef-

The operation is performed with an ordinary incisor file. The first step is to cut ofT the anterior end

nipper and

then

file

them

laterals,

and

Then using

this

where they contact the

of the superior corners

to the length decided upon.

length as a guide, a groove

filed

The

over the laterals and centrals.

along the groove and

across the entire arcade, teeth are then cut off

filed to a regular,

smooth edge, and

beveled backw^ards to give the appearance of a normal superior table.

the nipper alone

ing the arcade, the enamel

may

used without

first

upward and

chip

groov-

ruin the

appearance of the whole arcade. Polishing the crowns

the anterior face

â&#x20AC;&#x201D; After

scraped of

all

shortening the arcade

its

tartar

and crusta pe-

trosa with a curette, and then whitened wnth to give the appearance

young

teeth.

also performed with a small revolving

typical

w'ell

as the incrustations, can be

bluish-white color of

emery wheel applied

to the flexible shaft of a dental engine.

grooves, as

emery paper

This operation

young enamel

this

means the

removed.

The

can, however,

not be imitated, and besides, the yellow color will soon return. 3.

Renewal

of the cups (Bishoping)

the most impor-

attempts to make horses appear younger,

tant of

tlie artificial

and

performed intelligently upon horses that are not too

old,

together

with, the

above operations, even the vaunted

ANIMAL DENTISTRY expert

may

blunder.

The operation

121

consists

cutting

large cups in the inferior corners, smaller ones in the laterals

and mere dots

Fu;. 82A.

Wheel

Drill.

silver nitrate.

in the centrals

and then staining them with

Fig. 82B.

Fig. 82.

The Polishing Wheel.

Dental Engine.

The cupping process

engraver's gouge, revolving hand

drill,

performed with an or

by the modern

ingenious implement in vogue in the Chicago horse market,

AXLMAI.

122

consisting

the

equipped with a fectly

foot

human

used

cnL^ine

dentists,

circular cutting wheel, by which cups

normal shape and

Modus

I)i:X'IMS'rRY.

operandi:

size

of per-

can be made.

The horse

backed into a single

stall

Fic. 83.

and secured

8-Ycar-Oli!

Alouth Aladc

'-6"

the dental halter.

dental engine with the foot.

by "Bishoping."

assistant

works the

The operator holding

piece of the flexible shaft in the right

the hand-

hand and the jaw

Fic. 84.

9 or io-Ycar-01(l

the Other, cuts

first

Mouth Made

"7"

l>y

"Rislioping."

a large elliptical cup with sharp

commis-

sures in the table of the corner incisors, then smaller ones in the laterals

and small dots

in the centrals.

revolves with great velocity, the cupping

As the wheel work of but

the

ANIMAL DENTLSTRY. a

moment,

the horse stands complacently.

ner tooth has but a small table the cup

ners

cut across

frequently

a sharp

j[23

its

enlarged by

entire length.

made with

When

The cup

the cor-

filing

in the cor-

a rounded belly internally

commissure externally

to give a

and

more confusing

Fig. 85.

not more natural appearance. is

complete the arcade

When

the cupping process

dried and kept free from saliva by

wrapping the jaw behind the teeth with

The cups

a cloth or towel.

are then stained by applying a saturated solution

of silver nitrate with a stick

and then drying

immediately

Fig. 86.

Effect of "Bishoping"

by plunging the head

Teeth of 9

of a

12- Year-Old

burning match into

process immediately blackens the cavity.

over the table of the tooth

it is

it.

Horses.

The drying

the stain flows

filed off.

Shortening, polishing, cupping and staining the incisor teeth of a nine or ten-year-old horse

may

be so cleverly per-

SIXTH MOLAR,

ANIMAL DENTISTRY.

126

formed that

tlic

most circumspect study

to detect the alteration.

fail

of the

mouth may

In these cases the cupping

limited to the removal of the crusta petrosa within the in-

fundibula, thus leaving the cup with a perfect enamel boundary.

At that age the other retrogressive changes are not

pronounced and afford but

evidence to guide the diag-

little

(See Figs. 8^, 84, 85, 86.)

nostician.

Fig. 87.

The Ridiculous

When

Effect

"Bishoping"

Aged Horses.

horses are past the age of twelve years the results

of these operations are readily detected

by the interrupted

contact of the incisor arcades and especially inclination,

which

and which cannot be tables

])y

the angle of

never altered by any natural anomaly artificially

and the absence

changed.

The shape

enamel around the cup

will also

lead readily to detection of the fraudulent attempts to

very old horses appear younger.

(See Fig. 87.)

of the

make

CHAPTER

IV.

FUNCTION OF THE TEETH. The

teeth have but a passive function to perform as ac-

cessory organs of prehension, tion,

and as organs

mastication

and

insaliva-

Their uses are similar

of defense.

in all

species, varying but slightly in detail.

The

incisors serve the general purpose of holding food,

after the lips or

as a jerk of the

tongue have gathered

head detaches

between them, and

In the ingestion of de-

it.

tached food they serve no useful purpose mestic animals.

all

the domestic

any

mammals

of the do-

except rumi-

nants they are important organs of defense, and as such they

The

are most useful in the soliped. so

much

greatest

The

incisors of carnivora are

shorter than the canines that the latter

harm

to an

inflict

the

enemy.

canines of solipeds are

which animals they have no

common

only to

males,

special function to perform.

the carnivora and omnivora they serve the useful purpose of tearing attached food preparatory to mastication, besides

constituting the principal organs of defense.

mals they are

common

to both sexes

In these ani-

and they lock over each

other in a manner to hold fast to any object into which they are imbedded.

The molars mechanism

of herbivora

of mastication.

are

The

the

mill-stones

the

wide, roughened tables of

the superior molars, and the series of strong muscles which

move

the inferior ones

upon them, constitutes the

principal

features of a perfect grinding apparatus necessary to the

welfare of animals ingesting coarse, fibrous food.

In these

animals the molars grind the food perfectly, carefully and 127

ANIMAL DENTISTRY.

128 persistently,

abundant

and

same time incorporate

at the

In ruminants the food

ceous food.

passed by the

first

molars with only nominal conmiinution, but when gurgitated during rumination in the

non-ruminating animal.

tication

with the

saliva essential to the proper digestion of amyla-

and

re-

as carefully masticated as

Besides the function of mas-

insalivation, the molars

ified as tactile

might correctly be

class-

organs, as they readily detect the presence of

undesirable particles of food.

In the carnivora the molars serve to crack hard objects, as bones, into smaller particles and to divide large pieces of

ones simultaneously with surrounding the

flesh into smaller

particles with a slimy coat of saliva to facilitate deglutition.

In these animals they are not essential organs, as the food

may

be bolted without material impairment of the general

health, while in the herbivora the molars are as essential to

the

life

any

of the animal as

of the internal digestive organs.

PREHENSION. The

function of prehension

cisor teeth, canine teeth

performed by the

and tongue.

When

passed the incisors and canines, and the mouth

drawn backward

to the

prehension named

molars by suction.

lips, in-

the food has is

closed,

it is

The organs

the order of their importance in the

dif-

ferent animals are as follows:

Horse:

(i),

the lips;

(2),

the incisor teeth;

(3),

the

tongue.

Ruminants:

(i), the

dental pad; (3), the

Carnivora:

tongue; (2), the incisor teeth and

lips.

(i). the canine teeth; (2), the

the incisor teeth; (4), the

lips.

tongue; (3),

In the ingestion of liquids

the tongue alone performs the function by dashing the liquid well

backward

into the

mouth.

ANIMAL DENTISTRY. Omnivora:

(i),

the

teeth;

incisor

129

canine

the

(2),

teeth; (3), the lips; (4), the tongue.

(In sheep and goats the hps are very motile and serve to

gather attached food as

in the horse.)

MECHANISM OF MASTICATION. The organs

of mastication

comprise

The

superior max-

the inferior maxillary, the premaxilla, the molar teeth,

illary,

the tongue, the hard palate, the cheeks, and the masseter, the internal pterygoid, the temporalis, the digastricus, the

external

pterygoid,

the

stylo-maxillaris

and

the

sterno-

maxillaris muscles.

The

superior maxillary

united by sutures to

its

contiguous

and to

its

fellow by a wide,

mouth

form

facial

and cranial bones,

process extending across the

flat

roof.

imbedded portions

ties the

with

bony

its

an immovable bone, closely

receives into six deep cavi-

of the superior

molar arcade, and

fellow and premaxilla constitutes the upper jaw.

its

Its function is to

hold taut the superior molars and to form

the roof of the mouth.

The

inferior maxillary

movable bone

articulating

with the squamous temporal by a diarthrosis having imperfect rotatory

and perfect ginglymoid motion.

bone consisting

of a small

body anteriorly with two large

branches extending posteriorly to articulation.

xA.t

It is a single

the

temporo-maxillary

the anterior extremity of the

body

re-

ceives the six incisor teeth and along the superior margin of

each branch the six inferior molars. cation

medium

to serve as a carriage for the inferior molars, a for the

attachment of the muscles which move

to assist in forming the

The

Its function in masti-

premaxilla

bony Imundary

of the

and

mouth.

an irregular bone, which, with

its fel-

low completes the upper jaw anteriorly and contains the

ANIMAL DENTISTRY.

130

consists of a

1>ack\vard.

The upper

alveolar cavities for superior incisor teeth.

body and two branches extending-

branch passes apward and backward along the superior maxilla to the base of the nasal peak, where

formation of the maxillo-nasal notch.

The tongue of animals is membranous organ, having

enters into the

The lower branch

a thin plate loosely attached to its fellow

mouth

maxilla to complete the roof of the

and the superior anteriorly.

a very strong, motile, musculo-

attachment to the spur

a fixed

process of the hyoid bone posteriorly, and a free extremity anteriorly.

It is

membrane. thelium.

Its

held to the floor of the

upper surface

It is a tactile,

In mastication

organ.

mouth by

its

mucous

thickly paved with

epi-

gustatory, prehensile and masticating serves the useful purpose of keep-

ing the food between the molars while grinding-, and to assist in its

backward passage when mastication

The hard

palate

entire roof of the palate.

number

in a longitudinal raphe.

complete.

dense fibrous cushion covering the

mouth from the

presents a

incisor teeth to the soft

which meet

of transverse bars

serves the purpose of preventing

food from slipping freely outward, and to assist the tongue in

passing food backward.

The cheeks

arc

composed

of the buccinator

muscle cov-

ered externally with the skin and internally with the buccal

mucous membrane. It is yond the alveolar border cation

a loose curtain attached just beof each

molar arcade.

serves to keep the food between the teeth and to

complete the

lateral

boundaries of the mouth.

The masseter muscle

a thick,

wide and short muscle

located on the lateral aspect of the lower jaw.

tachment

In masti-

the maxillary spine and

zygoma and

insertion the external face of the lower jaw. that of closing the jaws slightly forward.

Its fixed at-

and drawing the

its

movable

Its function is

inferior maxillary

ANIMAL DENTISTRY.

The

131

pterygoid internus muscle occupies the same relative

ramus

position on the internal aspect of the

does externally.

attachment

Its fixed

as the masseter

the palatine crest

and the movable insertion the internal face Its function

jaw.

of the lower

that of producing lateral motion and as-

The

masseter to close the jaws, as follows:

sisting the

left

muscle acting alone draws the jaw to the right and the right

one to the masseter

and when acting together they

left,

in closing the

The temporahs muscle tal

bones, and

assist the

mouth. occupies the space over the parie-

inserted to the coronoid process and anterior

border of the ramus of the jaw.

when

ing the jaw, and

Its function

acting singly

produces

that of closlateral

mo-

tion.

The pterygoid extemus internally

and

in front of the

a short, thick muscle situated

temporo-maxillary articulation.

It originates on the sphenoid bone and

jaw

of the

pull the

below the condyle.

just

inserted at the neck

Acting together they

jaw forward and singly they produce a

lateral

mo-

tion.

The

stylo-maxillaris originates at the styloid process of

the occipital and

ramus

of the jaw.

inserted to the posterior border of the Its function

backward and depressing

The

that of

drawing the jaw

it.

digastricus muscle

located in the maxillary space,

originating on the styloid process with the stylo-maxillaris

and

inserted along the inner border of the

the symphysis.

Its

function

ramus toward

that of retracting

and de-

pressing the jaw.

The

sterno-maxillaris muscle originates on the cariniform

cartilage of the

jaw.

sternum and

Its function

The lower jaw

of mastication;

it is

inserted at the angle of the

that of depressing the jaw.

moved

every direction by the muscles

advanced, retracted, elevated, depressed

ANIMAL DENTISTRY.

132

and drawn

motion

In ruminants the lateral

to either side at will.

pronounced while

carnivora

in the

prevented

interlocking^ of the canine teeth, the beveled molars

by the

and the ginglymoid character peds the lateral motion

of the articulation.

The

nominal.

rodents and

motion

prominent

degree

herbivora.

The upward movement, which course a prominent movement

most

forcible,

animals, but

possible to a normal

an exceptionally powerful one

soli-

antero-posterior

the

all

in the solipeds

and ruminants. ^lastication

The mouth laris

effected in about the following manner.

opened by gravity, aided by the stylo-maxil-

and digastricus muscles;

then

swung

to the side

and slightly forward by the pterygoids, temporalis and masseter,

and then diagonally upward by the combined

the masseter, internal pterygoid and temporalis. these

movements

keeping the bolus as they

come

During

the tongue and buccinator are engaged in in

position to be caught

between the teeth

together.

Mastication

used at a time.

unilateral, only

Herbivora

minutes and then will.

effort of

shift the

will

one side of the mouth

chew on one

side for a

few

next bolus to the other, at their

CHAPTER

DENTAL DIAGNOSIS. Examination of the incisors (see page Examination

of the horse's

dental operations

done

113).

mouth preceding

the usual

the standing position, by palpa-

tion and inspection.

Palpation of the mouth. dark, deep cavern

common

irregularities

ploration.

may

its

For

be used.

â&#x20AC;&#x201D;As

the

horse's

mouth

examination for the detection of the

must depend

upon manual ex-

chiefly

this

purpose the mouth speculum or a gag

The

expert, however, requires neither, but

passes the hand v,nth the greatest freedom, ease and leisure to

any and

all

parts of the mouth, without inconvenience to

the horse or injury or danger to himself. that valuable attainment the halter is

accomplish

removed and the head

held from being thrown upward by an assistant holding

one hand on the nose and the other on the

The

poll.

diag-

nostician stands directly facing the horse, and passes the right

hand into the

left

commissure

of the

mouth, across the

interdental space into the space between the tongue and

molar teeth on the opposite

(left)

side.

The palm

hand faces the teeth and the dorsum the tongue. position the tongue of the horse

comfortable attitude and the mouth

of the

In this

not forced into any unis

not forcibly opened.

The hand may then be passed gently backward

to the fauces

and the fingers may be extended over the tables of the teeth without danger or injury.

The

opening the mouth too wide and

secret of success in

not

engaging the horse by

keeping the hand constantly moving. .133

When

the

hand

ANIMAL DENTISTRY.

134

kept stationary in the

mouth

resistance

immediately

of-

fered.

The versa. ,

right side

palpated with the

left

hand and

vice

Prior to the molar examination or immediately after, ,p.

" Search Lights."

the interdental space,

first

below and then above,

palpated

with the palmar surface of the thumbs to locate possible

bit

lesions or wolf teeth.

The novice may

use the

mouth speculum, which

will ad-

mit of free palpation of the teeth with the exception of the

ANIMAL DENTISTRY.

135

The hand cannot be

external borders of the molar arcades.

admitted freely into the mouth unless the speculum

opened

wide enough to provoke resistance, and besides the cheek

drawn

taut against the teeth and prevents

palpation

the borders of the molars.

Inspection of the mouth.

— Beyond

the

two molars

first

mouth cannot be satisfactorily inspected in the standing position. Only gross abnormalities can be seen, and these the

only to an unsatisfactory degree.

speculum and light,

artificial

light,

—a

With

mouth

the aid of a

reflector

incandescent

— with the head raised and the operator standing on an

elevation

possible to inspect the teeth, but in this pro-

cedure the tongue and the resistance to such forcible manipulations offered

by the horse, materially

interfere.

perfect

mouth can only be made in the recumbent posture with the head turned upward and the speculum adjusted, and then only by the aid of good light, a reflector if inspection of the

—

necessary.

pulling the tongue to

first

one side and then

mouth can be seen and

the other, every part of the

felt,

and

addition abnormalities can be searched for with steel picks.

DENTAL INSTRUMENTS—THEIR

USES.

FLOATS AND FLOAT BLADES. Floats are the principal instruments of the animal dentist.

They

are to the animal dentist

engine are to the

human

dentist.

what the

The

drill

and dental

float is a

simple con-

trivance consisting of a handle, shaft and head to receive

the blade

which may be either a rasp or

file.

The

entire

length should not exceed nineteen inches, divided as follows:

Handle,

The head

inches

;

shaft,

10V2 inches, and head, 3 inches.

open to receive the blade

at either

end and

perforated with two openings to receive the screws with

which the blade

kept taut.

There are many patent

affairs

ANIMAL DENTISTRY

136

on the market, some simple and others complex, which hold

Some

the blade solid by various means.

are equipped with a

mechanism by which the head can be placed

e.,

the straight and the angular

different

angles with the aim of combining two instruments

one,

All these inventions

float.

to date are but poor imitations of the old reliable simple

screw-head

few

will

and are neither durable nor

float,

hold the blade as solid as the old pattern.

These instruments are generally designated floats

;

and

practical,

they have been

as they ofTcr but

little

as the

House

use for more than thirty years, and

chance for improvement they

probably always retain the prestige of being the most

will

satis-

FiG. 89a.

Straight and Angular Floats, with Lines showing the Proper Angle of

Each.

Two

factory instrument of their kind.

styles are

recom-

â&#x20AC;&#x201D;

mended the straight float and the angular float. The Straight Float is used to file the lower arcades and the posterior two-thirds facilitate its

on flat

passage to the remotest teeth

a straight line

upon

of the superior arcades,

with the handle,

a plane the head,

wise throughout

its

â&#x20AC;&#x201D; face

its

when

e.,

downward,

entire length.

The

and

head must be the handle

â&#x20AC;&#x201D; must

lies

like-

posterior end of

the;

arcades, especially the inferior, cannot be reached with a float of

any other shape without opening the horses's mouth

wide enough to provoke resistance.

The Angular Float

used to

half of the superior arcades, which,

file

the anterior third or

owing

to the

inward cur-

ANIMAL DENTISTRY.

137

vature of their external borders, cannot

conveniently

reached with an instrument of any other shape.

The angular

float

should be of the same size and length as the straight

When

one.

its

head

lies,

face

downward, upon

a plane, the

center of the handle should be elevated two and one-half inches above the plane.

angles are

The

much

The short-handled

floats of greater

less convenient.

Float Blades should be of the rasp variety, tempered

hard enough to wear well and yet not so hard as to chip

from

filing the

hard enamel points of the molars.

straight float the cutting edges of the rasp

ward,

â&#x20AC;&#x201D;toward

the handle,

point forward.

in the

This arrangement

hands to make the its

â&#x20AC;&#x201D;and

float cut

its

In the

must point back-

angular they must

intended to train the

outward course instead

inward course, and thereby prevent prodding the back of

the mouth.

Fu;. 90.

THE FLAT FILE AND The

flat

rounded a rasp

and

file

and rasp

at the extremities

on the other.

first inferior

It is

should

RASP.

and have a

twelve file

inches

on one

used to round the

first

long,

side

and

superior

molars, and to shorten the canines and in-

cisors.

THE CLOSED MOLAR-TRIMMER OR CUTTER. The

closed trimmers are nineteen to twenty inches long,

including the handles, and have a head consisting of a

box

ANIMAL DENTISTRY.

138

and two cutting jaws, one

joint

which come together

long,

ting surface

one and a quarter inches

in perfect apposition.

dropped three-eighths

of an inch

The

cut-

below the

level of the

instrument better to enable the grasping of small

points.

should be made with a box

joint, the center of

no more than two and a quarter inches from the end of the cutting jaws. The forks and handles should be of no

which

less

than five-sixteenths inch

steel.

This instrument was primarily

intended

trim

enamel points along the arcades, both superior and

and

it is still

being used for

practitioners.

Its

this

the

inferior,

purpose by some veterinary

use for this purpose cannot, however, be

owing to the difficulty of placing them accurately upon the small enamel points located posteriorly on the arsanctioned,

FiG. gi.

Closed Molar Trimmer.

smallness of the points, the motility of the head and the great distance between the hands and the cutting end cades.

The

makes their applicability unskilled. Even in the hands of

of the instrument,

hands tist

of the

their use

amounts

to the cutting of

difficult

the

whatever happens to

be caught between the jaws. The closed trimmer should be used only projections at the extremities of the arcades perior and sixth inferior molars

the skilled den-

in cutting the

â&#x20AC;&#x201D; the

first

su-

â&#x20AC;&#x201D; for which purpose they are

indispensable.

THE OPEN MOLAR-CUTTER. The open molar-cutter

of the double-lever variety

also

an indispensable part of the dental outfit, and owing to the laborious work it must perform it should be powerful enough The style recomto cut any projecting tooth promptly.

ANIMAL DENTISTRY.

mended

139

twenty-four to twenty-five inches long and has a

head consisting of a

box

and two cutting jaws no more

joint

than one inch long which approximate within one-quarter of an inch

when

the instrument

center of the box joint

Six inches from the

closed.

a second one. to increase the lever-

FiG. 92.

The Cpen Molar Lever age.

The

fork between the joints

(square) bar is

steel,

Cutter.

while that from the

of three-quarter inch last joint

and handles

of five-sixteenth steel.

This instrument must possess strength neatness.

its

at the

expense of

can be opened wide enough to receive any

TH, CHICAGO,

Fig. 92A.

Plain

Open Molar

Cutter.

elongation of the horse's molars and will promptly cut, with

only nominal effort, any tooth

The

single joint

its

jaws

may

grasp.

open molar-cutters, unless made much

stronger and longer, will frequently disappoint the operator

and

will

always require a number of strenuous efforts before

a large tooth will yield.

ANIMAL DENTISTRY.

140

THE WOLF-TOOTH SEPARATOR AND FORCEPS. The

wolf-tooth separator

box

ing a

joint

a nine-inch instrument hav-

and l)ayonct-'point head, which contains two

cutting or wedging jaws approximating cacli other closely at the

end but open slightly along the cutting surface.

instrument

made use

of to extract wolf teeth

them between the wolf tooth and molar

This

by wedging

to disturb the alveo-

FiG. 93.

Wolf-Tootli Separator.

lar implantation

turb the tooth

and then pry them

may

view of the

be entirely dispensed with

separator may,

in addition,

dis-

utility of the separator,

veterinary dentistry.

The

be used to extract the sheddin^

Jhic.

Wolf-Tool incisors,

Their use to

precede the use of the ordinary wolf

tooth extractor which,

may

out.

g3A.

Forceps.

shedding molar caps, incisors and canines of dogs

and fractured incisors

of horses.

THE MOLAR SEPARATOR. The molar head consisting

separator of a

box

twenty inches long and has a

joint

and two wedge-shaped jaws,

projecting at a right angle, the edges of which

when

the instrument

closed.

It is

come together

used for the purpose of

loosening the decayed molar prior to the application of out-

ANIMAL DENTISTRY. ward

force with the extracting forceps.

141 Its

jaws are wedged

on either side

alternately, into the interdentia

cayed tooth until the implantation

of the

de-

disturbed.

Fig. 94.

Open Molar

Superior .Arcades.

Separator, for

THE CLOSED MOLAR EXTRACTOR. The

closed molar extractor

twenty inches long and has

jaws no more than one inch long and five-eighths of an inch wide, projecting at a right angle from the head.

Fic^.

The

forks

r;4.'\.

Closed Molar Separator, for Inferior Arcades.

and handles are strong enough to prevent springing when pressed forcibly together.

The jaws approximate within one-

eighth of an inch and are furrowed internally slipping from the tooth.

This instrument

I'lc.

prevent

indispensable in

95.

Closed Molar E.xtractor.

the extraction of molars, most of which are split into plates that cannot be held with an chiefly to extract split molars, but

vantage even when the crown

open forceps.

may

whole.

narrow

It is

used

be utilized to ad-

The

dental equip-

ANIMAL DENTISTRY.

142

merit containing only one extractor should, therefore, con-

which can only be

lain the closed variety instead of the open,

applied in the extraction of molars having

full

crowns.

Fu;. 96.

Closed Molar Extractor, with Curved Handles.

THE OPEN MOLAR EXTRACTOR. The open molar

extractor answers the same general de-

scription as the closed, with the exception that the jaws are

five-eighths of an inch apart

when

the instrument

closed,

and that the forks form an abrupt drop of one inch, inches from the head. forks

The

object of the curved or drop

to prevent the handles

before the tooth

lifted

from

Fi;:.

Open Molar tor

may

five

from striking the incisor teeth its

cavity.

The

closed extrac-

97.

Extractor.

be similarly curved, but owing to the fact that

when

they are applied to the entire crown the handles are wide

enough apart is

to pass the incisors

not as essential as

between them, the curve

the open ones.

THE ANGULAR MOLAR-CUTTER. The angular molar-cutter of the Its

same

size

twenty inches long, and

and pattern as the closed molar trimmer.

jaws extend from the head at an angle of about forty-five

degrees, and open in the shape of a

crown

of the first

fit

the triangular

inferior molar.

This instrument

used solely for the purpose of beveling

ANIMAL DENTISTRY. and to cut projections

inferior molars

the

first

size

on the

first

143

superior molars.

It is

nominal

a useful instrument,

The same work on

but not an essential one.

the superior

Fig. 98.

Angular Molar Cutter.

molars can be accomplished with the closed cutter and

and the

first inferior

can be beveled with the

file

file,

to the de-

sired point without cutting.

Fig. 98a.

Handles

for Figs. 92, 92a, 94, 94a, 95, 97

and

98.

THE INCISOR NIPPERS. The

incisor nippers

a simple instrument about ten

inches long, with a screw joint to bring the cutting edge.

power nearer the

has cutting jaws which curve claw-like from

Fig. 99.

Incisor Nipper.

come in perfect apposition when the instruclosed. The cutting surface should be no less than

the head and

ment

five-eighths of an inch wide.

This instrument

shorten the incisors and canines.

may

used to

also be used to

ANIMAL DENTISTRY.

144

/ /'

cut the sharp elong-ation at the extremity of the

first

superior

molar.

THE MOLAR CROWN CUTTER. The molar crown ally called,

cutter or claw cutter, as

occasion-

answers the same general description as the open

molar-cutter, with the exception that the cutting- jaws drop at a right

angle from the head and curve toward each other

like a pair of claws.

The jaws have

a cutting edge of

less

than three-quarters of an inch, and part three-sixteenths of

an inch when the instrument

Fig.

decayed one when extraction

are used

â&#x20AC;˘â&#x20AC;˘-.

ioo.

Molar Crown

remove the crown opposing

They

closed.

a is

Cutter.

decayed tooth, or that of a not deemed advisable.

THE MOUTH SPECULUM. The mouth speculum is indispensable in a dental practice. It may consist of a simple oblong loop of one-quarter inch iron bar, a wooden gag to insert between the molar teeth, or a double bar that is made to open as wide as necessary with a screw. These simple affairs may be made to answer the purpose

of the

costly

ratchet speculum, which has recently use.

The

come

ratchet speculum consists of

incisor arcades, upper

mechanism by means lips to a point

and

complicated

into quite general

two cups

fit

the

and lower, connected to the ratchet

of curved bars following the line of the

behind the commissure of the mouth, thus

ANIMAL DENTISTRY.

145

They have

leaving the fissure oris free from obstruction. the advantage also of opening the

Fic.

sired,

and the disadvantages

ratchet

may break

slip

mouth

any width de-

loi.

when

being none too

reliable.

The

the jaws of a powerful horse

Fig. 102.

are set against

its

strength.

Slipping of the ratchet

frequent accident after the catches have become constant use.

a very

worn from

ANIMAL DENTISTRY.

146

I'IG.

LO3B.

l-ic.

103c.

ANIMAL DENTISTRY.

The mouth speculum

I47

used only for operation

recumbent position, and especially when an animal the influence of an anaesthetic. is

useful only to the plebe

in the

under

In the standing posture

and novice.

obstructs the free

use of large instruments in the standing position, and

unnecessary for the minor operations.

THE TOOTH The Iowa

tooth chisel

veterinarian.

CHISEL.

a recent invention, the artifice of

consists of a strong

At one heel

shaped as a horseshoe.

lag screw, while on the other heel

The

blows of the hammer.

mouth while the other

heel

iron

a chisel inserted as a

a head to receive the

end

passed into the

kept outside.

Its object is to

chisel

band

break or loosen teeth that cannot be grasped with forceps. It is

undoubtedly an instrument of some value, especially

the extraction of broken fangs, as chisels of different

can be equipped with

dimensions and shapes to meet each

re-

quirement.

OTHER INSTRUMENTS. The above ments

a description of the

essential instru-

of a dental outfit for a veterinary practitioner.

is,

however, undeniable that many others might be added to the advantage of the dental branch of veterinary surgery.

There

room

for the addition of

many instruments

of vari-

ous shapes, styles and patterns suitable for special purposes.

For example, extractors

for the superior arcades should be

wider than those for the inferior; those for the right side

might be curved toward the

toward the

mouth

left,

and those

right, so as to bring the

at the

median

for the left side

instrument out of the

line; those for the last

molars might be

longer and have smaller heads and shorter jaws, to pass

more tors

freely

between the teeth and ;

finally all cutters, separa-

and extractors might be made specially for superior,

ANIMAL DENTISTRY.

148

inferior, posterior, anterior, right or left

tage of

tlie

work

dental surgeon.

At the present time there

no standard dental instru-

Each manufacturer and each practitioner has

ment.

particular idea as to

what constitutes the appropriate and as a

of instrument for each particular purpose,

an unfortunate state of chaos exists

in the

veterinary dental instrument costly, as

by making them

cannot reduce the cost

change

his

style

result

veterinary dental

makes

This unfortunate condition

instrument shop.

to the advan-

the

manufacturer

in large quantities.

for the better in this connection will

come when

the dental operations are regarded as being of sufficient im]K:)rtance

warrant the adoption of standard methods

operating, which in turn will create a

demand

for standard

instruments.

Trephines, chisels, punches, curettes, and the dissecting

instruments used

demand

animal dentistry are too well

known

description here.

RESTRAINT. Floating, filing and trimming the teeth of horses can be

â&#x20AC;&#x201D;enough

to de-

The minor

dental

accomplished without provoking resistance

mand any

forcible

means

of restraint.

operations are accepted with remarkable complacency

The only necessary restraint horse from backing away from the operator

the great majority of horses. is

to prevent the

and from elevating the muzzle out and instruments. single stall

on the

This

leather halter

at a

comfortable height

reins with the dental halter. is

hands

done by backing the horse into

and securing the head

pillar

of the reach of the

The ordinary

not satisfactory for this purpose because

one side or the other will press against the cheek and prevent the free passage of instruments along the teeth.

The

dental halter consists of a leather-covered iron loop

ANIMAL DENTISTRY. fifteen inches

long and nine

strap

Whenever

ropes.

hemp,

long-

reach the pillars of a the

The

adjustable to any sized head.

are ordinary half-inch

stall,

tie

The

poll

two-inch heavy leather with numerous buckle-

make

pillar or to

with a single poll

inclies wide,

strap and a ring on each side for the

holes to

140

tie

ropes,

enough

ropes

encircle the

any ordinary width.

stall of

owing

tie

to the construction of the

cannot be tied low enough on the

pillars to

hold the

Fig. 104.

Horse Properly Secured

for the

head down to the proper height, to the lower

end of the

Simple Dental Operations.

a third

halter, passed

rope or strap

tied

between the fore legs

around the withers and back again between the fore legs to the halter.

open room,

field

this addition a

or box

stall

person to steady the head.

horse can be secured

with only the assistance of one (Fig. 105.)

In the absence of the dental halter dental operations

should be performed with the aid of an assistant, to hold

ANIMAL DEXTISTRV.

head with one hand on the

tlic

poll

and the other over the

nasal bones.

Fig. 105.

Satisfactory

Method

of Securing a Horse for Simple Dental Operations,

Without the Use of

Major operations,

e.,

Pillar Reins.

repulsion of teeth,

etc.,

and minor

operations upon vicious horses, require the recumbent posi-

FiG. io5.\.

Lucas' Dental Halter.

tion table

and the use is

of the

mouth speculum.

The

operating-

par excellence the best restraining apparatus for such

ANIMAL DENTISTRY. operations because for inspection

151

brings the head to a comfortable height

and operation.

Anaesthetics are seldom necessary

perform

operations and frequently they are harmful in that

dental

they

favor the aspiration of blood and saliva into the trachea.

Local anaesthetics are not applicable tal

any form

to the den-

operations upon animals. Floating,

performed

may

in the

require

trimming and cutting the teeth should be

filing,

the

standing position.

The

extraction of teeth

recumbent, but only occasionally.

phining the skull can be performed

in the

Tre-

standing posture

with the aid of the twitch and dental halter, but the repulsion of teeth

must never be attempted without recumbent

restraint.

Chiseling, punching and sawing operations require perfect restraint in the

recumbent

position.

CHAPTER

VI,

DISEASES AND IRREGULARITIES OF THE TEETH. NECROSIS OF THE TEETH OF HERBIVORA. Synonyms: mentitis.

—

Dentitis

Pulpitis.

Perice-

Pcridentitis.

Alve()lar-]:)criostitis.

Decayed

Caries (erroneous).

teeth.

Fig.

io6.

Molars Predisposed to Decay by an Open

Clianncl

Through

the

Crusta

Petrosa of the Infundibula.

The

infundibula.

Openings of channel at table. Pulp cavity. (Tn the slmrt [old] tooth the pulp cavity

already

closed.)

Definition:

—A

total necrosis of

one or more molars of

herbivorous animals, of inflammatory origin, due to

mary

pri-

or secondary infective inllammation of the pulp.

Etiology:

— The

entrance of food 152

into

imperfectly

ANIMAL DENTISTRY. closed infunclibiilum

more than 95 per cent of The crusta petrosa, which

the cause of

the decayed molars of the horse.

should hermetically seal the infundibula,

and thus leaves an entrance channel

The pulp

153

therefore the

first

found wanting

for infectious matter.

structure to be involved in

the inflammatory process, from which source

through the apical foramena to the blood periosteum and bone.

traverses

vessels, alveolar

In rare cases the infectious matter

admitted directly to the alveolar periosteum through imper-

gums, the space between the

fect

teeth, or

posure of the periosteum while shedding

Fig.

Figure

106.

Openings of the infundibula, througb which food enters the tooth.

atheromatous degeneration dental artery, and

of the radicals of the superior

external

causes in a few instances.

violence are the determining

In these latter circumstances the

the last structure to be involved in the inflammatory

Systemic disturbances, especially a "ricket dia-

process.

by organic diseases or poor quality or

thesis" induced ficient

temporary

107.

Table View of Tootli Sliown

pulp

the

Cystic tumors located directly upon the root,

predecessor.

through the ex-

insuf-

forage during the period of growth, are predisposing

influences.

Pathological

ondary,

the basis

of the horse.

ends

Anatomy:

The

â&#x20AC;&#x201D;Pulpitis,

either primary or sec-

from which to study the decayed molar disease process begins with pulpitis and

finally in self-extraction of the tooth.

Between these

:54

ANIMAL DENTISTRY

Fig.

Necrosis of an Inferior Molar

the

io8.

Early Stage, with Perforation from

Table to Root.

ANIMAL DENTISTRY two events

155

the following chain of abnormalities occur:

(i)

extension of the inflammation to the blood vessel, nerves and

periosteum;

formation at the

abscess

(2)

root

pointing-

through the peridental plate into the sinuses or surface of the skull; (3) destruction of the blood supply of the tooth;

and

(4) death, desiccation

splitting of the tooth;

(5)

im-

paction and decomposition of food in the cavity between

and necrosis

of the alveolar

split sections;

(7) self-extrac-

The duration of the process is from The above chain of conditions is,

three to fifteen

the split section

;

(6) osteitis

border from pressure of the tion.

years.

followed to the letter

every instance.

Fig.

intense periostitis

may

course,

For example, an

109.

rapidly loosen

tooth

from

cavity and, by admitting infectious matter around

duce extensive great

length

osteitis of the jaw.

and

In the

the

tooth,

gravity, prevents

the

self-rejection

cavity,

and as

a result the loose,

the of

inferior molars periostitis.

This condition

when

Primary

it,

young animals

the

inferior

its

prothe

denture,

tooth from

its

dead tooth perpetuates and

augments the inflammation and tumefaction rounding bones.

not

the

seen principally

sur-

the

the primary lesion has been alveolar pulpitis

caused by the open infundi-

ANIMAL DENTISTRY.

156

Fig.

A The

A. I,

B, C. tion.

Superior Molar

in the

no. Early Stage of Decay.

table.

Openings into tlic tooth admitting food. The same tooth split longitudinally to reveal

its

internal condi-

ANIMAL DENTISTRY. bulum

the

inferior

arcades

157

points

frequently

known

surface of the jaw and constitutes the well

dental

(See Fig. io8.)

fistula of the inferior maxilla.

The

the

and canine teeth are not susceptible to the

incisor

condition.

Diagnosis:

â&#x20AC;&#x201D; The

molar tooth of the horse reaches the

advanced stage of decay unobserved the

incipient

progress

stages

without

apparent discomfort to the animal. or tumefaction of jaws or picion of decayed teeth.

most instances, as

The

mouth usually

signs

clinical

fetid breath, fistula

create the

sus-

first

In the absence of these outward

signs they are only encountered accidentally in palpations

mouth during

of the

dental operations.

nosis of a decayed molar

made when

The

earliest diag-

the infective inflam-

mem-

mation extends rapidly into the respiratory mucous

brane, before any gross changes occur in the tooth.

these cases the unilateral fetid nasal discharge leads to an

examination for abnormal (open) infundibula Anorexia, rejection

superior molars.

one of the masti-.

partially

cated food, dislike for cold water or turning the head to one side while masticating, are occasional signs of

incipient

stage, but

the

diagnosis

decay

in the

must be confirmed by

better evidence.

The

relative

decay of the teeth of horses

terially in locating the offending

perior molar,

and

its

hood, of

owing

its

member.

ma-

will assist

The

fourth su-

position in the center of the arcade

unstable neighbors during the second year of coltthe most

common

seat of the disease.

Out

of a total

two hundred decayed teeth observed, one hundred and

nineteen were fourth superior molars. the third superior

The

fifth

and fourth inferior were next

while the remainder were divided quite evenly first

superiors, the sixth superior

molars.

The second

superior

superior, in

order,

among

and the remaining

the

inferior

was not found decayed

until

ANIMAL DENTISTRY.

158

two hundred and thirty-second case was investigated,

the

showing that

this

Treatment:

moval

of the

tooth

â&#x20AC;&#x201D; (i)

not frequently decayed.

Removal

the tooth; and,

Removal

opposing crown.

(2),

re-

the palpable duty

in dealing with the decayed tooth of the horse, but in the

Fig. Ill

Advanced Stage A. B. I,

of Necrosis in a

The tooth. The table. I. The opening through which

uncomplicated case removal be accomplished

a simple

Superior Molar.

the tooth

became

infected.

warranted only when

manner

(forcep

can

extraction).

When

and

too short to grasp firmly with the forceps, removal of

decayed molar produces no apparent inconvenience

ANIMAL DENTISTRY. crown

the opposing

ment

ample remedy pending the develop-

of serious complications.

a foreign (dead) body,

encysted

in a

protecting

The operation

remov-

accomplished with a claw cutter.

The removal

lOO.)

decayed molar, although

may become

wall and cause no further trouble.

ing a tooth crown

159

of teeth

(Fig.

accomplished by either of the

following methods

By extraction wnth forceps. By repulsion with punch and mallet. By removal of the external alveolar By splitting with chisel and mallet.

(i) (2) (3) (4)

EXTRACTION WITH FORCEPS.

(i)

Equipment: and

sizes,

tion, a

— Open

separating

tractor,

plate.

molar extractor, closed molar

forceps,

operation

hardwood

performed

fulcra

in the

ex-

assorted

recumbent

posi-

mouth speculum.

Indications:

method

universal

enough

— Forcep extraction should be adopted as the remove molars having crowns long

to grasp fijrmly.

Even though trephining may be

necessary to reach the existing secondary condition, forcep extraction should,

Restraint: positions

—

possible, precede the trephining.

Choice between the standing and recumbent

must be decided by the probable complacency of

the patient and the position the horse

skill of

backed into a single

brought downward within easy reach.

may

and confined

the operation

movements of the jaw a mouth speculum The mouth speculum should, however, be

forcible

be applied.

avoided

stall

The head must be

to the pillars with the dental halter.

resisted

For the standing

the operator.

possible, as

the instruments.

will interfere

with the free use of

For the recumbent position the patient

placed in a dorso-lateral attitude with the

adiusted and the head inclining upward.

mouth speculum

Anaesthesia

not

ANIMAL DENTISTRY

160

advisable, owing- to the greater danger of l)lood flowing into

the trachea.

Modus operandi tooth.

â&#x20AC;&#x201D; The

recjiiircmcnt

first

from

lifted

injury to the teeth

upon which the fulcrum

loosening process

the other until

felt

to be well loosened.

on one in

side,

then on

Tor-

the spaces.

extractor

now

outward traction

implantation.

When

Undue

haste or the ap-

must be avoided and care must be sudden movement of the head.

in a

adjusted firmly to the crown and the

fulcrum block placed as near

fragile

The

placed.

then applied with the extracting forceps until the

taken to prevent fracture

firm

first

can be easily closed

accomplished by wedging the molar

plication of great force

The

cavity without fracture, or

its

separator into the inderdentia,

sion

to loosen the

safe to assert that the tooth that cannot be

loosened cannot be

tooth

its

head as possible.

will readily

the tooth

Gradual,

bring the tooth from

its

divided into two or

segments the manipulation must be carefully exe-

cuted to prevent fracture.

Accidents:

â&#x20AC;&#x201D; The

extraction of molars

The

without danger.

not

possible misfortunes are:

entirely (i)

Frac-

ture of the tooth which will necessitate removal by

some

more complicated method: with the

jaW' of

(2)

wounding the

the forceps; (3) excessive

palatine artery

hemorrhage from

the dental artery.

Fracture of the decayed tooth that

with secondary disorders

moval

of the

may

opposing crown.

l)e

uncomplicated

by the simple

re-

there are catarrlial or

fis-

treated

tulous complications repulsion will be necessary. 2.

will

Palatine hemorrhage

endanger

life.

The

serious

and unless arrested

accident occurs as a result of the

horse chewing forcibly upon the end of the internal jaw of the forcep while being adjusted to the superior tooth.

soon as the accident occurs the operation must cease and

ANIMAL DENTISTRY. mouth must be packed

the

full of

161

cotton, waste,

oakum

any other packing material that can be promptly furnished.

When finger

there

delay in procuring a suitable packing the

must be kept over the wound After the mouth

flow of blood.

closed tightly by encircling

and the patient

packed

them with

backed into a

reins for five to six hours,

to temporarily arrest the

stall

when

full

the jaws are

dozen wraps of cord

and kept on the

the packing

may

pillar

be safely

removed.

Hemorrhage from the

be very profuse, but

dental artery

never serious.

may It

occasionally

arrested by

packing the cavity with wadding of cotton or oakum.

^tL

Fig. 113.

Decayed Tooth Due

â&#x20AC;&#x201D;The

After-care:

fresh packing every

Primary Alveolar

tooth cavity must be

day

for a

(Ostertag).

Periostitis

wadded

with

week, at which time a careful

examination of the cavity must be made to remove sequestra or fractured segments of bones, which

healing of the wound.

may

two years the opposing tooth

have elongated into the vacant space and

ming (2)

to the level of

its

delay prompt will

will require trim-

arcade.

REPULSION OF TEETH WITH PUNCH AND MALLET.

â&#x20AC;&#x201D;Three-quarter-inch

Equipment

circular

trephine,

one

inch circular trephine, bone chisel, punch, iron mallet, scalpel,

artery forcep, dissection forceps,

rette, razor, antiseptics

mouth speculum,

and packing materials.

cu-

ANIMAL DENTISTRY.

162

Indications:

dicated forcep,

when

â&#x20AC;&#x201D; Trephining

the tooth

and when there

of the sinuses.

more or

less

crown is

skull to repulse teeth

tlie is

in-

too short to grasp with the

a complication of fistula or catarrh

In secondary catarrh of the sinuses wnth

accumulation of purulent matter, trephining

Fig.

114.

Mallet.

an essential adjunct to tooth extraction, even though the extraction

accomplished with

tlie

forceps.

perfonr.ed to evacuate the accumulated

admit the free irrigation of the catarrhal

Trephining

secretion

and

mucous mend)rane,

Fig. 114a.

Straight Punch.

as well as for the purpose of admitting the

punch

to repulse

the tooth.

The following sion

Fourth and

are the molars that are fifth

removed by

repul-

superior, sixth superior of old horses,

6HAHP S SMITH, CHICAGO.

Fi(-,.

114i!.

Curved Punches. first,

second, third and fourth inferior and the

fifth

and sixth

accompanied with considerable tumefaction

inferior wdien

the jaw.

â&#x20AC;&#x201D; The

Restraint:-

recumbent position,

lateral posture, af-

ANIMAL DENTISTRY. mouth speculum securely

fected side uppermost, with a justed,

never satisfactory.

The

ad-

The

the proper attitude for the repulsion of teeth.

standing posture is

163

operating table

par excellence the best method, as the head can be more

firmly secured than with

anaesthesia

casting

the

sometimes harmful, as

state blood readily finds

its

way

Location of the openings:

must be situated so that

Fig.

General

unconscious

the

into the lungs.

â&#x20AC;&#x201D;^The

the

harness.

opening

the

skull

punch can be placed on

115.

Cut Representing the 8 Teetli Whicli Can Tc Repulsed and the Location of the Opening for Each.

straight line with the long axis of the tooth.

(See Fig 116.)

The transverse range will vary slightly with the age of horse. In the young horse well toward the median line of head and

the old one nearer the maxillary spine.

The

the the lon-

gitudinal range will vary according to the tooth to be re-

pulsed, the fourth, fifth or sixth.

mined

after the animal

the operation.

The exact

seat

deter-

secured and otherwise prepared for

The hand

placed into the mouth and a

ANIMAL DENTISTRY.

164 iingci"

pressed against the cheek opposite the decayed tooth,

and from the bulge thus made

made upward to In the young horse

measurement

animal's age.

made molar

for the

backward direction

young animals

the cheek externally a

by the

a point indicated

must be

a slight variation

of the fifth molar.

reflected

The

sixth

backward beneath the

eye and cannot be satisfactorily repulsed.

For the

inferior molars the openings are

very border of the jaw sixth, in

which instance

every case except for the

made upon

part of the tumefaction caused the third, fourth and

must be made

fifth

at the

and

fifth

the most prominent

For

by the diseased process.

inferior molars,

marked backward

for the

made

due

allowance

direction of their

(See Fig. 115.)

fangs.

The openings must be made with due deference

for the

following important structures (i)

Steno's duct.

(2)

Lachrymal

(3) .(4)

(5)

canal.

Glossofacial artery and vein.

Superior dental canal and contents. Inferior dental canal and contents.

(6) Superior maxillary division of the trifacial nerve

near

its

exit

from the

skull.

In the repulsion of the superior teeth complicated with catarrh a single additional opening tal

made

to drain the fron-

sinus and to give free access to the maxillary sinus, as

well as to drain the frontal sinus into the nasal fossa.

opening

located in an oblique direction

ward four centimeters from

This

downward and

the nasal canthus.

in-

(See Fig.

151)

Opening the

Skull:

â&#x20AC;&#x201D; This

step of the operation requires

the consecutive dissection of (i) the skin, (2) the subcutane-

ous areolar tissue and muscles, (3) the periosteum, (4) the bone, and (5) the mucous membrane.

ANIMAL DENTISTRY. Repulsion of the Tooth:

mouth with a the left hand

165

â&#x20AC;&#x201D;The right hand

placed in the

finger pressing firmly against the tooth while directs the punch.

The

assistant

then

di-

rected to strike firmly with the mallet until the impression of the

blow

is felt

forcibly until

by the finger against the tooth, and then driven from

its

mit an impression into the mouth

punch

cavity. is

Failure to trans-

an indication that the

not advantageously located.

Fig.

1 1

Cut Representing the Proper and the Improper Methods of Placing the Punch to a Tooth to Be Repulsed. A. B.

Proper method punch on Improper method. ;

Aftercare: is

made

a straight line with tooth.

â&#x20AC;&#x201D;As soon as the tooth

resume the standing

removed the patient

position.

The

frontal sinus,

maxillary sinus and nasal fossa are then freely opened into

each other by breaking

them.

The

down

the fragile septa separating

cavities are then emptied, irrigated,

with antiseptic cotton.

and wadded

Daily irrigation with 3 per cent zinc

ANIMAL DENTISTRY.

166

sulphate solution and renewal of the wadding for two weeks

or until the discharge ceases,

the necessary after-care.

Sequelae:â&#x20AC;&#x201D; (i) Alveolo-nasal

(2) persistence of

fistula,

the catarrh and reaccuniulation of pus in the sinuses, (3) persistence

opening (chronic nasal

the

fistula),

(4)

sep-

ticaemia, (5) deglutition pneumonia.

Alveolo-nasal

fistula,

allowing the free passage of food

from the mouth to the nasal cavities or sinuses result of repulsion of teeth of the

upper jaw

common

aged horses

or from allowing food to pack tightly into the tooth cavity

before

has had an opportunity to close.

spontaneously

decay of the

tion with the forceps.

by the application of the teeth

They

also occur

molar or from extrac-

first

In the old horse they are prevented

of a gutta percha plug

between the crowns

bounding the vacant cavity and

the

young

horse by preventing the packing of food into the cavity.

wadding placed between the crowns

tight will

after

repulsion

not interfere with the healino' and closure of the cavitv.

The treatment

of the chronic dento-nasal fistula consists of

removing the impacted food from the nasal cavity or sinus by trephining and the application gutta percha into the channel.

of a

first

For

removed.

fistula

molar the surgeon may choose between

method and the

prevent further packing

against the plug the opposing- crown of the

permanent plug

obliteration of the channel

this

by removing the

external alveolar plate and the opposing crown. 2.

Persistence of the catarrh will

ation and

precise after-care.

demand

second opera-

This sequel

the result

of failure to properly drain the sinuses into the nasal cavity,

or careless and dilatory irrigation. 3.

Dental

fistula

have their origin

or chronic sinuses of the lower jaw,

bone necrosis,

failure to

entire tooth or the proper tooth.

Reopening

and removal

of the insultinc: agent

remove the

of the

the remcdv.

wound

ANIMAL DENTISTRY. Septicaemia

the result of improper

167

method

of op-

erating, the use of septic irrigation fluids, or neglect to

irri-

gate properly.

Deglutition pneumonia results from the flow of blood,

antiseptic fluid or pus into the lower air passages during the

operation.

It is

caused either from anaesthesia or the use

Fig. 117. JNIolar

Denture of

Young Horse, to

of the fall

the

Which Extraction

Difficult,

Owing

Deep Implantation.

Speculum, which prevents deglutition of

fluids

which

into the pharynx.

(3)

REMOVAL OF THE EXTERNAL ALVEOLAR PLATE. (Williams' Operation)

Equipment:

â&#x20AC;&#x201D; Bone

dissecting forceps, septics,

chisel,

narrow-blade

artery forceps,

and mouth gag.

saw,

scalpel,

mouth speculum,

anti-

ANIMAL DENTISTRY

168

Fig. ii8.

Molar Dc"li;re rf Mature Aliddle Acred Horse.

Fk;.

Molar Denture of an

.\s:e(l

llie

Horse,

Sliallow

19.

Wliich

Fxtraction

Implantation.

Easy,

Owing

ANIMAL DENTISTRY. Restraint:

form

â&#x20AC;&#x201D; Lateral

anaesthesia

recumbent

local

169

position,

cocainization,

under chloropreferably

the

former. Indications: sally for the

molars.

â&#x20AC;&#x201D; This

operation should be adopted univer-

removal of the

second and third superior

first,

Applied to the fourth or

fifth

superior molars a de-

formity of the face results from the removal of the extremity of the maxillary spine,

and besides

has no advantages

Fig.

I2IA.

Mouth Gag. Fig.

Fig. 120.

121.

over repulsion for these teeth.

removal of the these first

The Most Appropriate Specuhim

first,

for

Williams' Operation.

Saw.

Chisel.

may

also be applied to

second and third inferior molars, but

has no special advantages over repulsion.

For the

three superior molars, especially the third and second,

the operation

almost indispensable, and

out-classes re-

pulsion because the almost perpendicular wall of the skull at this point line

prevents the placing of the punch on a straight

with the tooth, and

the opening,

finally, in

repulsing the third tooth

properly placed, necessitates division of the

ANIMAL DENTISTRY.

170

superior maxillary branch of the

ist step.

—

fifth

shave and disinfect

Clip,

cranial nerve near

its

foramen.

exit ivoni the infraorhital

a liberal

space at seat

of operation.

2nd

step.

— ]\Iake

a longitudinal

two inches

skull) incision

long-

(parallel to long axis of

through the skin and muscles

directly over the root of the affected tooth.

3rd step.

— Separate

the soft tissues from the bone from

the incision to the gingival margin in the mouth.

4th step.

on each

— Saw through the skull along the interdentium

side of the tooth

;

then chisel the bone fiap loose

superiorly.

5th step. chisel,

the released plate of bone loose with the

and remove with the forceps.

6th step. chisel

— Pry

— Release and

elevate the tooth by prying with

and mallet.

7th step.

— Close

incision with sutures

and arrest hem-

orrhage by packing from wnthin the mouth. 8th step.

— Remove

crown

opposing molar to prevent

packing of food into the cavity. After-care. Irrigate

— Remove

the packing in twenty-four

hours.

mild antiseptic solution, and keep

daily with

in-

cision well protected with clay paste.

(4)

REMOVAL OF TEETH BY SPLITTING WITH

This operation superior or

first

indicated for the removal of the

inferior

held in the forceps.

first

molars when the crowns cannot be

performed

the recumbent posi-

mouth speculum.

Recently an inven-

It is

tion with the aid of a

tor has placed

CHISEL.

upon the market

a tooth chisel

shaped

a horseshoe, that can

be used to chisel any molar tooth.

Such an instrument

of service in splitting

and removing

badly diseased fangs when major methods are unwarranted,

and to serve as

wedge

to dislodge the remaining fangs of

Animal dentistry.

171

teeth accidentally fractured in attempts to

extract

them

with the forceps.

EXTRACTION OF THE INCISORS. Owing

to the deep implantation

and curvature of the

fang, the incisors cannot be readily extracted

nary method, except

become shortened.

by any

ordi-

extreme old age, when the fang has During youth and middle age their exin

FlG. 122.

Cut Showing the Great Length ancl Curvature of the Incisors, that Prevents Forcep Extraction.

traction can only be accomplished

by removal

of the anterior

alveolar plate and then prying the tooth out with a chisel or elevator.

and the

The mouth

subject

tied shut

placed

With

membrane and gums

are

the recumbent position

with several wraps of sash cord

around the muzzle.

osteum

knife

and forceps the mucous

removed over the

fang, the peri-

scraped off with a curette and the bone removed

ANIMAL DENTISTRY.

172

When

with a chisel.

the fang

entire length the chisel

exposed throughout

driven under the tooth and

its is

pried out.

The

incisors of the solipeds

decayed to the point

requiring

fractures from falls or IjIows

may

and ruminants are seldom Longitudinal

extraction.

loosen a part of an incisor

and provoke decay of the remaining portion, and occasionally a persistent

temporary with a long fang

may demand

attention to improve the appearance of the mouth, but aside

from these instances extraction

seldom required.

The

temporary incisors are frequently extracted to give the horse the appearance of being one year older, or

ding

when

the shed-

delayed beyond the usual period.

EXTRACTION OF THE CANINES OF HORSES. The

deep, curved alveolar cavity of the horse's canines,

the incisors, prevents forcep-extraction, in the

They

animal.

are

removed only

in the

young

recumbent posture,

by the removal of the external alveolar plate and prying with the chisel as

The

in the

case of the incisor.

canines are seldom decayed except from pulpitis and

periostitis following injuries to the tooth or jaw.

CARIES. Synonyms: of teeth. titis

(It

— Caries

dentium, decayed teeth, ulceration

must not be confounded wMth alveolar perios-

of herbivora).

Definition:

process

— Caries

signifies rotteness.

diseased

might be appropriately defined as a biochemic de-

composition of the dentinal substance originating at one or

more points

of a tooth.

might also be defined as a pro-

gressive disintegration of a tooth's substance, penetrating

from the surface toward the center. Etiology:

—The exciting cause of caries

erosion or frac-

ANIMAL DENTISTRY.

I73

ture of the enamel covering, through which channel acids

and micro-organisms gain access to the sensitive parts

The

tooth.

of the

acids dissolve the calcium salts as the micro-

organisms decompose the organic material, producing conjointly a gradual

gnawing away

progress of disintegration

the

substance.

The

frequently arrested by the for-

mation of a protecting wall around the cavity not unlike the pyogenic wall of an abscess of the is

This process

soft tissues.

due to the calcification of the intra-tubular substance of

the dentine.

tooth has

The

In other events

progresses until the entire

become destroyed.

acids responsible for the dissolution

the

cal-

careous matter of the tooth reach the teeth by being

in-

gested as such, or by the transformation of food products into acid substances. tive parasites

The micro-organisms

are the putrefac-

which normally inhabit the mouth and which

only become pathogenic at the proper opportunity. to isolate a specific

The

organism have thus

Efforts

far failed.

Impairment

predisposing causes are numerous.

the general health during the period of dental evolution, rickets,

pregnancy, irregularities of the arcades, meat

and uncleanliness of the mouth are the chief conditions

diet re-

sponsible for the disease.

Susceptible animals. of

all

escape of

man

pathological conditions. its

mature

caries is the most common Few mature human beings

ravages upon the teeth. life,

It is essentially a

disease

although when the predisposing causes are

legion even the temporary teeth

markable extent.

may

be attacked to a re-

In the domestic animals

occasionally in the old dog,

hog and

ruminants are comparatively free from

observed

cat.

Solipeds and

caries.

In these ani-

mals decay of the teeth takes the form of an inflammatory disintegration.

(Necrosis, see page 152).

dissolution of the herbivorous tooth

In rare cases the

may undergo

a disin-

ANIMAL DENTISTRY.

174

tegrating process which neither resembles caries (the non-

inflammatory condition)

nor necrosis

inflammatory

(the

condition), and as a result leaves the impression that caries is

existent in the herbivorous animals.

human

nation,

teeth having

Caries, the disease

uniform cause, course and termi-

its

not seen in the herbivora, and the short

the other domestic animals places the disease

lives of

among

the

rare disorders in veterinary practice.

Treatment: is

treated by

â&#x20AC;&#x201D; The

carious tooth of dogs, cats and pigs

prompt extraction.

Leveling, burnishing and

stopping the carious cavity, which constitutes the universal

treatment of the disease

the

human

tooth

an attainment

not expected of a veterinarian at the present time, and the

Fig.

White's

I22.\.

Dog Speculum.

rarity of the indications will doul)tless

always prevent

its

introduction into the veterinarv college curriculum.

EXTRACTION OF THE TEETH OF DOGS.

When

the teeth of carnivora are loosened from disease

their extraction

when

easily accomplished with the forceps, but

the implantation

not disturbed they can seldom be

extracted without fracture. firmly

imbedded

The

canines,

into a curved cavity

and

especially, will

are

defeat any

ordinary method of removal.

best accomplished

The

extraction of the teeth of dogs

first

disturbing the implantation with a cutting bone for-

ceps along each side of the fang before applying the extracting forceps.

The

molars, canines and incisors

may

ANIMAL DENTISTRY. treated in the a

dog

same manner.

for tooth extraction

I75

handy method

of securing

to tie a piece of tape around

each jaw behind the canine teeth, then an assistant stands astride of the dog, pinches the

head taut between

his

knees

and holds the mouth open with the tape as the operator appHes the instruments.

This method

the operating table, which places the

even preferable to

mouth

an awkward

position for extraction.

ABNORMAL ERUPTIONS OF THE TEETH. Shedding

of the incisor teeth

depends upon "growth pres-

sure" from the permanent successors.

the forming tooth

Fig. I22B.

Baker's

does not adjust

Dog Speculum.

itself directly

upon the apex

of the

fang the latter

may remain wedged between two

teeth through

life.

incisors the result

When

If this is

same condition

left

contiguous

exists in all the

a complete double set of incisors.

such abnormalities are observed early enough the

temporary teeth should be extracted. best

temporary

In later years they are

undisturbed.

The canine teeth frequently remain covered with the gums for several years after their usual period of eruption, and thus cause a more or less painful irritation to the mouth. The

condition

observed most frequently

in the

six

and

seven-year-old driving horse by the resistance such animals

ANIMAL

176 offer to the

adjustment of the

while driving.

which

DENTIS'I'RV.

The

l)ridle

condition

or by shaking the head

met by lancing the gums,

best done with the curved scissors.

The molar teeth having temporary prcclecessors, the second and

grow

first,

reasons occasionally cease to

third, for obscn-re

sufficiently to force out the

temporary ones, and as

the latter are not sufficiently stable to perform the function of mastication,

result

becomes

the whole, area

a large

infected and the

tumefaction of the jaw.

When

the tem-

porary teeth arc extracted the dead undeveloped permanent

Fig.

Temporary Tooth Due

Persisting

123.

Faulty Eruption of

Its

Permanent

Successor.

ones are found lying loosely beneath them. is

found chiefly on the lower jaw.

The

This condition

condition will always

respond promptly to the removal of both the temporary and

permanent teeth involved three teeth

On third,

may

in the process.

One, two or

all

be affected.

the superior jaw osteoma of the maxilla over the

second or

pressure of the

growth

first

molars

permanent

often produced

teeth

when

1)y

their

backward dow^nward

blocked by a wedged temporary tooth.

These conditions occur

young horses from two

to five

years old and are often mistaken for decayed teeth or tumors

ANIMAL DENTISTRY.

They may be

the temporary tooth

serious import.

Blisters

Removal

tumor by trephining

producing a chronic

some danger

difficult to heal.

CYSTS.

name we apply

the

They

of the greater portion of

fistula that

DENTAL Dental cysts

will

from apex to base with a large

trephine will hurry the recovery, but there of

and time

from two months to one year.

seldom persist longer. the

unilateral or bilateral.

already shed the condition must

be treated on the expectant plan.

remove the condition

]77

to cystic

growths oc-

curring along the course of the artery supplying the tooth.

They vary growths

in size

from small sacs the

that entirely

matous degeneration

They

marble to

size of a

the sinuses and even cause bulging

They

of the facial bones.

molar tooth.

fill

are probably the result of athero-

the wall of the nutrient artery of the

frequently

become

infected and cause

Regard-

alveolar-periostitis, chronic nasal catarrh, or both. less

of size,

they completely destroy the nutrition of the

tooth by obliterating the nutrient vessel, and after they expel their contents the

peridental covering,

dead tooth, entirely stripped

is left

of its

During

projecting into the sinus.

the early stages of the resulting catarrh a diagnosis of the real condition, before operation,

aiTected first

will finally

impossible.

tooth so

become loosened and thereby

time reveal the true cause of the catarrh.

for the

In rare in-

new mass The dental

stances the projecting root becomes encysted in a of fibrous tissue

and remains intact through

cyst explains the nature of the cause of

life.

some

of these ob-

scure cases of chronic nasal catarrh which are described as

primary.

When

recognized these cysts are treated by re-

pulsion of the afTected tooth, which

located by palpation

or inspection after the skull has been trephined.

The

disease

ANIMAL DENTISTRY.

178 is

confined to the fourth,

originates in the young- animal.

fifth

and sixth superior molars, and

ODONTOMATA. Synonym:

— Tooth tumors. — A dentinal growth

Definition:

origin, occurring

Etiology:

non-infiammatory

on the fangs of the teeth.

— The cause of these growths

obscure.

The\^

ANIMAL DE/NTISTRY.

179

are occasionally determined by monstrosity of the crown.

The crown

will

be found expanded

extending well toward the median

may weigh upward Treatment:

directions, often

line of the palate.

They

pounds.

â&#x20AC;&#x201D;The

undisturbed.

left

to five or six

in all

odontoma causing no inconvenience is When ablation becomes necessary through

decay of the tooth or infection of the surrounding perios-

FiG.

An Odontoma

126.

of the 2nd Inferior Molar

Weighing

Pounds.

The White

Portion Is the Table Surface of the Original Tooth.

teum, they are removed by skull over the

dividing

first

trephining and chiseling the

most prominent part

of the tumor,

into sections until repulsion

and then

possible.

BRACHYGNATHISM. Synonyms chin.

â&#x20AC;&#x201D; Parrot

mouth.

Receding

jaw.

Receding

ANIiMAL DENTISTRY

180

Definition

—A

congenital deformity

which the supe-

rior incisors overlap the inferior.

Etiology

—A congenital deformity of obscure cause.

deformity consists of a deficiency inferior maxillary, or an

in the

The

proper length of the

abnormal elongation

of the pre-

maxilla.

Symptoms

— Overlapping

superior ones with rior

of the

inferior incisor

or less elongation of the

and sixth inferior molars.

The

by the

first

supe-

condition becomes more

Fig. 127.

Typical Ca?e of Bracln-gnathism.

and more aggravated with age.

the molars

wear away

the inferior incisors reach the palate behind the superior incisors.

Nature, however, seems to meet the condition by

hardening of the palate and rounding the premaxilla so as to

accommodate cisors.

There

the gradual transgression of the inferior inwill

be difficulty

in the

prehension of attached

food, and the animal will be difficult to keep in

good condi-

tion.

Treatment

— Parrot

mouth

defect for which horses

ANIMAL DENTISTRY must be condemned inferior incisors

an inspection for soundness.

must be shortened by

time, and the elongated molars

to the level

useless

Filing or cutting a considerable portion of

either the inferior or superior incisors teeth,

The

from time to

filing

must be trimmed

Shortening the superior incisor

of the other teeth.

and inadvisable.

181

harmful, as these

having never been subjected to the influence of wear,

Fig. 128.

Typical Case of Prognathism.

are sensitive to the very tables, and will bleed

crown

much

of the

removed.

PROGNATHISM. Synonyms

â&#x20AC;&#x201D;Undershot.

Prominent

jaw.

Prominent

chin.

Definition

â&#x20AC;&#x201D; A congenital

deformity

incisors overlap the superior.

which the

The deformity

inferior

consists of a

ANIMAL DKXTISTRY

1S:>

deficiency in the proper

leni^tli of

the jiremaxilla or an elon-

gation of the inferior niaxilhi.

Symptoms in

— Prognathism

which animals

exists

most

frcMfiiently in

characteristic of certain breeds.

however, occasionally encountered

in the horse, the

dogs It is,

molars

sharine the abnormality.

Fig.

A The

A, B. C.

1st

(Ostertag).

beveled molars.

inferior

Treatment incisor

129.

Typical Case of Parvignatliisni

molar absent.

— Tn the dog, none.

In the horse the superior

crowns are shortened from time

to time

filing

and

the molars are kept level.

PARVIGNATHISM.

— Scissor mouth. Ijevcling the molars. Definition— A congenital deformity consisting of a de-

Synonyms ficiency in

tlie

proper width of the lower jaw, or more prop-

ANIMAL DENTISTRY.

183

Fig. 130.

Parvignathism, with Beveling of the Buccal Surface of the Inferior Molars

{^.

Fig. 131.

Samples of Beveled Molars Removed.

ANIMAL DENTISTRY.

Ig^

erly speaking, a deficiency in the proper distance

the inferior arcades, causing a

bevehng

between

of the molars.

—

Symptoms The l)eveHng is usually confined to but one The molars of one superior arcade become beveled side. from without inward entirely obstructing the

toward the affected

motion

lateral

The condition is more molars, and

frequently com-

side.

plicated with decay of one or

mastication

Parvignathism

the advanced stage.

almost impossible

one of the most serious irregularities of the horse's mouth.

Treatment

— With

the large lever cutter (Fig. 92), the

beveled crowns of the entire superior and inferior arcades

must be trimmed almost to the with the

first tnolars,

level of the

and the decayed

gums, beginning

teeth,

any, must be

This treatment, while placing one-half of

removed.

molars entirely "out of commission,"

w^ill

all

the

be met by prompt

relief to the patient.

PROJECTIONS ON THE FIRST SUPERIOR AND SIXTH INFERIOR MOLARS. Definition

arcades of of

enamel

all

— A universal irregularity existing

the molar

mature horses, consisting of sharpened points

at the anterior

end of the superior arcades and the

posterior end of the inferior arcades.

Etiology

—The

aggravated forms due to such gross de-

formities as brachygnathism or congenital or acquired deficiency in the proper length of

one or both arcades are not

The

large elongations occurring

included

in this

category.

at the extremities in either of the

deficiency in the length of the opposing arcade,

due to

but

this

are equal.

molar arcades are usually

minor irregularity the lengths

the arcades

These points are caused by the position

muscles of mastication.

The

fixed attachments of

muscles of mastication except the masseter

and

of the all

the

external

ANIMAL DENTISTRY.

185

pterygoid are located posteriorly, and therefore

backward

the jaw

lift

The absence

any

muscle with an anterior fixed attachment to antagonize

this

slightly

at each contraction.

backward traction

The

ties.

the cause of these universal irregulari-

masseter's influence in that connection

insuf-

ficient.

Treatment

— In

mucosa and require

the

wound

driving horses the anterior ones filing.'

PROJECTIONS ON THE SUPERIOR CORNERS. (See Fig. 72.)

At about the age

on the

of seven years there appears

superior corner incisor a sharp enamel point which in most instances will disappear during the three

This irregularity

mension

ensuing

due to a congenital deficiency

of the inferior corners.

They disappear under

influence cited in the preceding paragraph,

ward

traction

by the muscles

years.

in the di-

the

the back-

e.,

of mastication.

ACQUIRED ELONGATION OF THE MOLARS. Definition ties

— Projections

of the

molars into vacant cavi-

on the opposing arcades.

—The common cause of elongation of

Etiology ety

the loss of a molar

extraction.

this vari-

They occur

also

from the decayed molar that offers no adequate wearing surface for

its

opponent.

become excavated from

Symptoms

Occasionally in old age the molars a defect in texture.

— Defective

mastication, rejection of food, ac-

cumulation of food beneath the buccinator and tumefaction

jaw are the signs usually directing the attention to

of the

such teeth.

Palpation and inspection will reveal a large

tuberous projection involving one or two teeth cade,

one

and a vacant tooth cavity or a decayed tooth,

ar-

in the

ANIMAL DENTISTRY.

186

opposing one.

In the aggravated forms there will also be

a considerable excavation of the

Owing

jaw

in the

vacant cavity.

to the frequency of decay in the fourth superior

molar

the condition appears chiefly in the region of the fourth inferior molar.

Treatment

—Trimming

to the level of the arcade with

young animals and extraction in the aged In horses more than fifteen years old the implan-

the lever cutter in patient.

tation

so unstable that the cutting process

may

loosen the

tooth.

Fig. 132.

Typical Case of Elongation of the 4th

Inferior

Molar (Ostertag).

OPERATION OF CUTTING ELONGATIONS. Restraint

— Standing

position with the dental halter and

The speculum

without the use of the speculum.

will pre-

vent placing the cutter evenly over the crown of the tooth.

Equipment

— Dental halter, open

molar cutter,

floats

and

file.

Modus Operandi

— For the

cutter to the tooth with the

supports

them

by the

left side

left

handles.

guide the head of the

hand, as the other hand Place

the

left

handle

ANIMAL DENTISTRY. of the cutter against the chest

187

and open

with the right

hand, then adjust the jaws over the base of the elongation. Retract the

left

hand and cut

off the

tooth with both hands.

In the superior arcades the great volume of the elongation

may

necessitate the application of considerable force.

(Also Fig. 92.)

Fig. 132a.

The Open Molar Lever

must be taken

aged horses, and

Cutter.

in the

case of the molars

at the extremities of the arcades, that the tooth

not loos-

ened by a sudden movement of the patient's head. cutting the elongation the arcade

Fig.

Handles

and

file.

may be

132b.

Care

After

leveled with the floats

(Also Fig. 98a.)

for Figs. 92, 92a, 94, 94a, 95, 97

and

98.

Small pointed projections on the inferior arcades cut with the closed molar trimmers

when they

are

too narrow for the large opening of the lever cutter.

ENAMEL

â&#x20AC;&#x201D;

Synonyms Sharp teeth. Enamel points of herbivora. Definition

â&#x20AC;&#x201D; Sharp

POINTS. Lateral

enamel projections.

points of enamel at the table extrem-

ANIMAL DENTISTRY.

188

ity of the lonp^itiulinal ridges of the

molars, occurring rilong

the buccal border of the superior arcades and the lingual

border of the Etiology

inferior.

â&#x20AC;&#x201D; Enamel

They

not pathological.

points are

are a normal part of the dental mechanism, serving the pur-

pose of a rake to maintain fibrous forage between the teeth.

Being normal structures

their causes are strictly of an in-

tended, predisposing character, namely: (i) (2) (3)

The relative narrowness of the inferior molars. The relative narrowness of the lower jaw. The ginglymoid character of the temporo-maxillary articulation, limiting the lateral motion of

the jaw. (4)

The

(5)

The herbivorous

longitudinal ridges, the enamel of which ren-

ders possible the formation of points. characteristic

which three

substances of unequal densities are

wear.

The normal wear of the teeth. Symptoms Under strictly natural conditions they (6)

â&#x20AC;&#x201D;

not harmful, but from the

horse faces.

tication

artificial influences to

subjected they frequently

wound

The widely accepted impression by obstructing the

founded upon ing of the

facts.

free lateral

superior molars.

of the

effect

The wounds

cated on the cheek opposite the

The former

first

which the

the buccal sur-

that they limit mas-

swing

Their sole harmful

mucous membrane.

are

jaw

the

not

wound-

are usually lo-

and second, and

are caused by the

fifth

friction

sions of the

latter by the forcible movements The lesions vary from slight eromucous membrane to large ulcer-like patches

one inch

diameter.

of the bit

and bridle and the

of the masseter muscle.

Other parts of the cheek and the

tongue are seldom wounded.

between the ages

Wounds

of 5

They

attain the greatest size

and 8 years.

of the cheeks

which are being perpetually ag-

ANIMAL DENTISTRY.

189

gravated by enamel points limit mastication and favor gasIn drivers, runners and saddle horses they

tric indigestion.

are the greatest sources of annoyance.

The expert reinsman

promptly recognize their presence by the horse's be-

will

havior

Lugging, side-reining, ptyalism, tender-

harness.

ness about the seat of

bit,

manifestations of pain from the

symptoms of these lesions. Treatment The treatment consists of filing with the Trimming with the closed molar trimmers floats and file.

bridle are

â&#x20AC;&#x201D;

(Fig. 91) preceding the filing cannot be defended

argument.

logical

this

by any

instrument could be accurately

adjusted to the very tips of the points, as they are intended,

they would materially lessen the labor of the operation, but as only the very skillful operator can properly accomplish this feat, the use of the in the interest of

trimmers should be dispensed with

judicious and scientific dentistry.

few

carefully directed strokes of the fioat equipped with the rasp

blade will rapidly blunt the sharp projections to the desired

Rounding the borders

point.

aim

of the molars

in dressing the teeth of a horse should

harmful.

The

be to simply blunt

the enamel points along the course of the arcades and to

"round up" the

first

superior and

The wounds from

smooth as an ivory

ball.

thus prevented and

there will

tication

from the too

The

whole arcade.

first inferior

molars as

the bridle are

be no interference with mas-

liberal use of

instruments along the

closed incisor trimmers are indispensable

to trim the projection at the extremities of the arcades,

on the used.

first

inferior

molar the angular trimmer

may

and be

(Fig. 98.)

OPERATION OF TRIMMING AND FLOATING THE MOLARS. Equipment

â&#x20AC;&#x201D; Straight

trimmers, twelve-inch halter.

float,

file,

angular

float,

closed molar

a pail of water, and the dental

ANIMAL DENTISTRY.

190

Restraint

backed into

— The horse

a single stall

and fastened

The

dental halter.

secured

the

stan(iin_£^

position,

to the pillar with the

halter ropes are fastened to the pillars

low enough to hold the head

When

proper height.

at the

the construction of the pillars prevents tying the ropes low

enough, an additional rope

fastened from the halter at the

lower extremity of the iron band and passed between the forelegs around the withers, and back again

between the head

legs to the halter, for the purpose of preventing the

from being held too high. in

securing horses

are wanting.

This method

in a loose

also serviceable

box or paddock where

stalls

(See Fig. 105.)

The mouth speculum must be dispensed

with, as

tively interferes wnth the free use of the instruments

provokes resistance, which also

The

and

twitch

contra-indicated, even on the vicious animal.

The aim ation,

otherwise avoided.

posi-

securing the horse, as

to avoid the use of

performing the oper-

any force that

Examination of the Mouth

—

First,

will

be resented.

the incisors are in-

spected to determine the age and the presence of any harmful

disorders or irregularities.

the

thumbs

jaw

Then

the palmar surface of

passed along the interdental space of the lower

to locate possible bit lesions,

and without withdrawing

them they are turned upward against the interdental space of the

upper jaw to palpate for wolf teeth.

lars are

Third, the

mo-

palpated by passing the hand backwards between

the tongue and molar arcades.

Modus Operandi the twelve-inch

file,

(See diagnosis.)

— The canines may to prevent

first

be blunted with

wounding the hands, but the

blunting process must be limited to the very tips of the

crowns, owing to the fact that a short blunt canine gives the

appearance of age, and thus leaves an opportunity for just criticism.

The second

step of the operation consists of

trimming the

— ANIMAL DENTISTRY.

191

ends of the arcades, with the closed molar trimmers, but only use.

when The

the projections are long

enough

warrant their

superior molar and the sixth inferior alone

first

require this treatment, in the normal mouth.

The remainder is

of the operation

— the floating and

performed as follows: 1st.

filing

• .

Float the posterior two-thirds of the right superior

arcade, with the straight float, the anterior one-third with

the angular

float,

and then blunt the anterior end of the

molar with the twelve-inch 2nd.

first

file.

Observe the same routine on the

left

superior ar-

cade.

Fig. 89.

Fig. 89a.

Straight and Angular Floats, with Lines showing the Proper Angle of

Each.

3rd.

Float

straight float, first

the

entire

inferior

left

and bevel smoothly the anterior end

molar with the twelve-inch

4th.

with

arcade

the

of the

file.

Observe the same routine on the right

inferior ar-

cade. 5th.

Extract wolf teeth,

any

exist,

and complete the

operation by blunting any sharp projection, on the superior molar, that

may

exist

behind them, and which could not have

been reached prior to their extraction. It will

be observed that

in the

above routine the arcades

beginning with the right superior, are dressed consecutively.

The work on each one next, until

all

completed before passing to the

four have been perfectly attended

to.

The

ANIMAL

192

DENTIS'I'RY.

only ol)jcction to this order of manipulations

time consumed consideration,

changing instruments. the

all

work required

completed before the instrument

the loss of

When

speed

of each instrument

a is

laid aside, as follows:

Float the posterior two-thirds of the superior ar-

1st.

cades, and

of both

all

inferior arcades, with

the straight

float.

Float the anterior one-third of the superior ar-

2nd.

cades, with the angular float.

Blunt and bevel the ends of the arcades with the

3rd.

twelve-inch

file.

Whatever

adopted,

will

be found advantageous to

Fig. 90.

form the

hal)it

of following the routine in either plan, in

order to avoid omissions and unnecessary examinations of the

mouth

done.

to determine the

It is

amount

of filing that has been

an error to use the floats promiscuously and to

Such methods promore systematic work.

repeatedly palpate to note the results.

voke resistance, which

avoided

METHOD OF USING THE FLOATS AND

FILES IN

THE FORE-

GOING OPERATION. It is

undeniable that one operator can

of horses,

and

fact,

float

the teeth

use any of the dental instruments

without provoking the least resistance, while another

have more or

So marked

less troulile

will

with every animal approached.

the difference in this connection that bystand-

ANIMAL DENTISTRY. ers frequently gain the impression that

I93

some operators exert

The

a mysterious influence over their patients.

solely in avoiding the use of force. forcible

secret Hes

horse will resent

opening of the jaw, forcible insertion of the hand

backwards into the molar region,

forcible

restraint,

and

injury to the soft structures inflicted by improperly directed

In avoiding these manipulations the secret

instruments. found.

Forcible opening of the

mouth

unnecessary

Fic. 133.

Position of

using the

Hands

float.

the instrument

to Float the Right Superior

As only

may

Molar Arcade.

the edges of the arcades are floated

be passed unobstructed to their very

end without opening the mouth more than half an the lower arcades the

hand must

dental space to guide the shaft of the the

mouth

opened

slightly

inch.

be passed into the interfloat,

more than

and, as a result, in

floating

the

superior ones, but to prevent resentment, the hand in the interdental

space must not be used to force the

open when the animal attempts to close upon

it.

mouth

Its pres-

AXl.MAL DI-'-XTISTRY.

194

ence there

mouth.

simply to i^uidc

Injury to the hand

tlic

cannot be squeezed when the mouth

usually provoked

manner by

in this

and not to open the

tUjat

prevented

prevent closure of the moutli

Ijy

keeping

closed.

where

Resistance

forcibly attempting to

fear of being bitten.

operator must learn to place the hand only where

The

cannot

be bitten or squeezed, and the horse must be permitted to use

its

jaw ad libitum.

The

dental operation must not be a

Fig. 134.

Position of

Hands

to Float the Left Superior

fight for superiority in strength

and the patient's jaw.

Molar Arcade.

between the

The following

dentist's

hand

position of the hands

to guide the instruments will serve the purpose.

For the of the left

right superior arcade place the tips of the fingers

hand palm upwards,

just in front of the

commissure,

of the first superior molar.

hand and guide fingers of the

its

left.

into the interdental space, or, in

Work

shaft with the

other words,

front

the float with the right

palmar surface of the

In this position the finger tips are not

ANIMAL DENTISTRY.

195

passed beyond the outer border of the jaw (upper branch of the premaxilla) float

head

kept

but are fortified gently upon

against the outer edge of the arcade

flat

and not upon the table surface.

For the

left

(See Fig. 133.)

superior arcade pass the

left

hand, palm up-

ward, through the interdental space, from right to the tips of the fingers sure,

and

let

the

The

it.

protrude slightly from the

thumb

on the palate

rest easily

until

left,

left

commis-

the re-

FiG. 135-

Position of the

gion of the right

first

Hands

to Float the Left Inferior

the fingers of the

For the

Work

the float with the

shaft with the

palmar surface of

superior molar.

hand and guide the

Molar Arcade.

(See Fig. 134.)

left.

left inferior

arcade pass the

left

hand, palm down-

ward, through the interdental space, from right to

left,

under

the tongue, and

when

with the finger

tips,

tongue and

arcades (the dorsal surface to the tongue

left

and palmar surface

the

left

border of the tongue

direct the

reached

hand upward between the

to the arcades),

and

let

the

thumb pro-

AMMAL

196

trmlc

the

thr()Ui;li

commissure.

left

anterior end of the arcade finger,

and the wrist

l)i;\'riS'l'RV

h'es

position

the

between the tluimh and

first

this

kept Hat on the interdental space of

lower jaw, to keep the tons^ue from slipping beneath

tlie

The

float

worked with the

riglit

hand, and the shaft

guided by the palmar surface of the base of the thumb. fioat

head

kept

arcade, and not

flat

(^n tlie

tlie

Hands

tables.

For the right

same

Float

136. tlic

Riglil

Although the to train

left

hand

work

Molar Arcade.

was placed

the awdcward one,

to accomplish this feat, as

of placing the

left

hand

the

for the oppo-

the float with the

that will give universal satisfaction. sists

Inferior

inferior arcade i)lace the right

arcade, and

The

(See Fig. 135.)

relative i)osition as the left

site inferior

against the internal border of the

Fig.

Position of

it.

left

hand.

advisable

the only position

Another method con-

hand upright

into the interdental

space and guiding the shaft between the second and third, or third and fourth lingers.

Still

another method consists

ANIMAL DENTISTRY. of passing the left

hand

197

through

into the interdental space,

the right commissure, grasping the free end of the tongue firmly with the fingers and then passing

opposite commissure.

with the right hand, and the shaft

which

The

gently out of the

In this position the float

upward

slightly arched

right inferior arcade

others and as a result

worked

guided by the wrist,

into the roof of the

mouth.

dif^cult to float than the

usually found neglected posteriorly.

(See Fig. 136.)

Fig.

Position of the

Hands and

blunt the right

137.

File to Blunt the Right First Superior Molar.

first

into the right cominissure

superior molar place the

left

hand

between the cheek and the molar

arcades, then pass the twelve-inch

file

(in the right

hand)

through the interdental space from the opposite commissure to

its

guide

finger tips. it

tips of the left.

teriorly

Work

the

around the end and

Change

with the right hand and

file

side of the arcade with the finger

positions to round the arcade an-

and internally as follows

ward the nasal roof and the thumb

Place the into the

left

hand

to-

commissure to

ANIMAL DENTISTRY

198 retract

and elevate

then work the

it.

file

with the right hand.

(See Figs. 141-137.)

blunt the

in the left

left first

superior molar place the right hand

commissure, between the cheek and teeth, then

pass the twelve-inch

file

through the interdental space from

the opposite side to the finger tips of the right hand. the

file

with the

the right.

left

hand and guide

Change the

position to

with the linger

bhmt

Work tii)s

the anterior end of

Fig. 138.

Second Position of

tlie

Hands and

File

Rlunt the Left

l-'irst

Superior

Molar.

the tooth, as follows:

Place the palm of the

left

hand over

thumb retract and elevate the commouth, then work the file with the right hand

the nose and with the

missure of the

as in filing the opposite side. .

the

To left

tract

the

bevel the right

hand on the

(See Fig. 138.)

first inferior

inferior

molar place the palm of

border of the lower jaw, and

re-

and depress the commissure with the thumb, then work

file

with the right hand.

(Fig. 139.)

Change the

position

ANIMAL DENTISTRY. as follows

left

to right,

the

left

Pass the

file

and hold

199

through the interdental space from

upon the tooth with the thumb

hand, then work the

file

by short movements

of of

both hands.

bevel the

left first inferior

molar open the mouth

gently by grasping the tongue and turning in the interdental

space

with the right hand.

;

then work the

Position of the

perpendicularly

file

over the molar

The beveling process may be

FiG.

First

Hands and

pre-

139.

ImIc to

Revel and Blunt the Right First

Inferior INIolar.

ceded, to advantage, by

first

trimming the anterior angle

of the crowns with the angular cutter.

The above

(See Fig. 140

points on the molars

may

be blunted with but

little

without provoking resentment from the horse. ods

may

)

simply "a" method by which the sharp

serve the

labor,

and

Other meth-

same purpose, providing they can be

carried out without the use of force.

Occasionally a horse that has been roughly handled or

ANIMAL DENTISTRY.

200

one that has never l)econK' accustomed to l)eing handled about

the

mouth when

head, first

will

resent

attempt to open

the

Such animals can never be

approached.

conquered by force or rough treatment,

sufficiently to enable

the operator to properly carry out the procedure, but the use of kindness and gentle manijmlations to

few

the patient's confidence,

abandoned on account

dental

of resentment.

first

gain

operations need be It will

be found that

Fig. 140.

Position of the

ITaiifl

and

I''ile

Revel and RInnt the Left First Inferior

Molar.

the most resistance is

offered by such horses while the float

being adjusted to the teeth or while the hand

placed

in position to

being-

receive the float, and that the resistance

immediately ceases as soon as the

filing begins.

The

re-

markable fact that a horse will stand "at attention" while the rasping proceeds suggests itself as a

advantage of a resisting horse.

hand into the interdental space,

method

Instead of the

float

first

of taking

placing- the

may

first

ANIMAL DENTISTRY.

201

promptly passed into the mouth, and as the horse becomes attracted by the unusual sound and sensation produced the filing no further resistance

may

be offered and the hand

then be placed unresented into the interdental space to

guide the

float.

Enamel

points will recur in about three months, but not

to a sufficient degree to

the eighteenth

month

produce injuiy

after the operation.

Fin.

Position of the

Hands and

until the twelfth to

File

At the age

of five

141.

Complete the Rlnnting Process on the

Superior Molars, Externally.

to eight years their recurrence

more rapid than

aged

animals.

Modifications

â&#x20AC;&#x201D; \\'hen

one of the arcades contains a de-

cayed or elongated molar the normal arcades are floated

and

The

filed

before any attention

given to the abnormal one.

painful part of the operation

performed

last to

the resistance that might be provoked thereby, and

tooth

extracted, to avoid

working

avoid

when

bloody mouth.

ANIMAL DENTISTRY.

202

In very vicious animals the recumljcnt position

sary to properly trim

be neces-

molar teeth, hut such animals are

tlic

In our experience with

rarely encountered.

may

upwards

of fifty

thousand horses only two such cases have been met

was

a trotting bred stallion

Both

and the other

— one

hackney gelding.

animals would resent any attempt to place a

of these

mouth

float into the

striking viciously with

l:)y

In such cases the veterinarian

warranted

appropriate means of restraint,

tlie

fore feet.

resorting to an

the recumbent position.

FLOATING THE TEETH OF THE OX. The ox

head low, has an imyielding tongue

carries the

and

about the mouth that

and a strong

jaw^

for dental operations.

so unaccustomed to being handled

unwelcome subject These obstacles are met by securing makes

a rather

the head and neck to the post of the

stall,

an upward

and by keeping the mouth open with

inclination,

strong

speculum consisting of an ol)long loop of iron placed within the interdental s])acc. frail

The ordinary horse speculum jaw

to withstand the forcible

The

too

of an ox.

superior arcades are floated with the hand in the

same position

as in the horse, but in the inferior ones

kept

in the interdental

and

The

teeth.

float

space and not between the tongue is

directed from within

outward

follow the direction of the arcades.

Enamel

points are less harmful in the ox

owing

to the

toughness of the buccal mucosa, yet buccal wounds from sharp teeth are not

uncommon

animals past the age of

three years.

WOLF TEETH. Synonyms

— Remnant teeth.

plementary teeth. Definition sive teeth

I'^ye

Supernumerary

teeth.

Sup-

teeth.

— The wolf teeth

representing the

may

be defined as retrogres-

premolars

the

prehistoric

ANIMAL DENTISTRY horse.

They

ment but

203

are not the result of accidental dental developof the equine denture un-

normal part

a constant

dergoing degeneration under the influence of selection, as

"wisdom teeth"

the

man

lluence of civilization.

The

are disappearing under the in-

use of the bit through innumer-

abe generations appears to have rid the interdental space of the premolars.

Wolf

teeth are constant in foetal

and superior dentures, and many

life in

both the inferior

them never develop

the point of eruption, but instead degenerate,

and become

Those which

finally erupt

incorporated with the maxilla.

vary from small

homogeneous masses

of soft dentine to well

Fig. 142.

Wolf-Teeth.

developed teeth possessing istics of

all

the distinguishing character-

the herbivorous molar.

Symptoms

â&#x20AC;&#x201D; Wolf teeth

are harmless with the exception

of their possible interference with the overcheck bit or

plicated coach-horse rigging, such as bridoons.

effect

tion.

jaw,

upon

They have

the eyes, and are diagnosed solely by palpa-

Their position

more or

com-

the interdental space of the upper

less closely related to the first molar.

some

instances they are located on the inner aspect of the molar

and occasionally on the lower jaw.

Treatment

â&#x20AC;&#x201D;The

wolf tooth should be extracted, as

serves no useful purpose and

may

some time

interfere

ANIMAL

204

DKN'IMS'l'RV.

with the bitting ri^g^ing of a driving horse.

ment

of eye affection their extraction

able,

owing

They

In the treat-

particularly advis-

to the popular prejudice against them.

are difficult

extract without fracture because

their location j^rexents direct

outward traction and l)ecausc

of the impossibility of perfectly immobilizing the

Their removal

especially the lower jaw. first

head and

accomplished by

disturbing their implantation with the wolf tooth sep-

arator (Fig. 93) prior to the application of outward traction

with the forceps, or with the separator alone.

Fig.

143.

Supcrmimcrary Incisors of

6- Year-Old

Gelding.

SUPERNUMERARY TEETH. Definition

ber

'Jliey

any

â&#x20AC;&#x201D; Teeth

existing in excess of the normal

of the arcades, are designated as

must be

num-

supernumerary.

differentiated from wolf teeth, which are nor-

mal structure and from persisting temporary teeth, due to displacement of the permanent tooth germ.

Etiology jection of

germ.

â&#x20AC;&#x201D; The supernumerary teeth

more than one

This occurrence

der normal development,

one predominates. one another

stalk

from the

frequent

all

from the pro-

common enamel

not universal, but un-

the stalks degenerate as a chief

Whenever two

until tooth

result

development

more keep pace is

witli

well advanced, the

ANIMAL DENTISTRY. result at a

the formation and growth of

Some such

given point.

remain imbedded

teeth

205

more than one tooth

may

never erupt, but

the jaw along the arcade.

additional seventh molar frequently occurs behind the

This incident

sixth in either arcade.

Fig.

of the

the result of the

144.

Supernumerary Incisors of

backward extension

9-Year-Old Horse.

common enamel germ from

pre-

cocity of the sixth molar.

Symptoms

â&#x20AC;&#x201D; The

incisor arcades teeth.

abnormality

observed chiefly

the

which may contain an entire double row

In most instances one or

Fig.

two additional

incisors are

145.

Supernumerary Molars.

observed projecting of the arcade.

The

an irregular fashion to the table level

lateral incisors are

most frequently the

seat of the abnormality.

In the molar arcades they

may remain hidden through

ANIMAL

206

or remain un()l)scr\c(l until their existence

life,

DKX'nSTF-iV.

the treatment of diseased conditions

revealed

â&#x20AC;&#x201D; extracting,

trephin-

ing, etc.

Treatment

â&#x20AC;&#x201D; As

long as the supernumerary tooth pro-

duces no apparent harm no treatment

worse appear-

incisor arcades their extraction gives even a

ance to the arcade than

When

they had been

encountered within the sinuses

operations they are removed or

tal

cording to whether they are involved

left

undisturbed.

the course of den-

left

In the

advisable.

undisturbed,

ac-

the morbid process.

ELONGATIONS OF THE INCISORS. As decay

or loss of incisor teeth

a rare condition ac-

quired elongations of the incisors by growth into vacant cavities are also rare.

The gradual lengthening

of the

whole

superior incisive arcade as an animal becomes older

natural condition resulting from a gradual receding of the alveolar border, and the constant increase in the inclination.

The common

impression, especially

among laymen,

that

the elongation of the incisors prevents contact of the molar

denture

The only detriment

erroneous.

the evidence

they furnish of the real age of the animal, on which account alone their shortening

advisable.

incisors of the old horse

the

amount removed.

Shortening the superior

always harmful

proportion to

Prehension of attached food

im-

paired.

SHORTENING THE INCISOR TEETH. The

incisor teeth of the horse are reduced in length for

the purpose of disguising the evidence they furnish as to the age of the subject.

The popular impression

prevent contact of the molars is

physically impossible.

The

as the molars will permit

instances the veterinarian

that they

as positively ridiculous

incisors can only

wear

them, and vice versa.

as fast

In rare

re(|uired to reduce their length,

â&#x20AC;&#x201D; ANIMAL DENTISTRY. to hide the

crowns beneath the hps, when the

cover them completely, is

207 latter

no longer

which case only the operation

excusable.

The operation

performed only upon the superior

cade, as the inferior one

seldom inspected for

its

ar-

senile

changes. First, cut ofY the internal table angle

Modus Operandi of each corner tooth

and

file

them

to the length decided upon,

and then use the length as a guide for reducing the remainder of the arcade. Second, file a deep groove, through the laterals

and centrals connecting the new

table level of the corners.

Third, cut off the laterals with

enamel across the

Fig.

Fig. 145b.

14S.\.

Lip Retractor and Mouth Gag, useful

the nippers and

file

them

shortening incisor teeth.

to the level of the corners.

them

to the level of the laterals.

cut off the centrals and

file

Fifth, bevel the tables

backwards by patient

remove the crusta petrosa and

Fourth,

tartar

filing.

Sixth,

and polish with emery

paper.

In cutting the incisors great care

necessary to prevent

chipping of the enamel, which accident will leave an unsightly defect in the arcade.

cutting

the

transverse

The

groove

accident

completely

prevented by

through

the

enamel and by not grasping too much substance with the nippers.

It is

preferable to cut an incisor tooth by small

sections, rather than

by grasping the

entire crown.

ANIMAL DKNTISTRV.

208

EROSION OF THE ENAMEL. Definition

—A

disease of the anterior face of the superior

incisor teeth, cliaracterized l)y a i^ra(hial n])\var(l denudinu,- of

the external enamel covering.

Etiology

— The

cause depends solely upon a faulty con-

struction of the teeth, both anatomically and morphologically.

The

softness of acteristic

disease occurs

the teeth.

all

soft

animals having an observable

The dentine

hardness and the crusta petrosa

devoid of is

its

char-

deficient in qual-

Defective cementing of the enamel

ity as well as quantity.

to a

underlying dentine favors the gradual breaking

and wearing away and the habit

Iron feed boxes, cribbing

of the former.

gnawing hard objects hurry the denuding

process, but are never solely responsible.

Treatment appearance

— Polishing with

emery paper

to give a better

the only possible help.

TARTAR. Definition

— An

accumulation of calcareous matter along

the gingival margin of the teeth.

Etiology body.

It is

mucus on

— Tartar

simulates calculi in other parts of the

the result of the chemical action of saliva and

the calcium sa'ts of the food.

It is

composed

Phosphates

80.

Mucus

1.5

Ptyaline

Animal matter

7.5

Symptoms the gums. incisors;

— Tartar occurs as

yellow incrustation along

found mostly on the canines and

on the canines

frequently accumulates in large

In animals

quantities and gives the strosity

(odontoma).

crown the appearance

It is

of a

mon-

difTerentiated from the latter by

being readily removed, and from the normal crusta petrosa

ANIMAL DENTISTRY. by

its

lighter color

Treatment

209

and by not adhering firmiy to the crown.

—Tartar

removed with

a curette or

file.

produces slight irritation of the gums.

FRACTURE OF THE TEETH. Fracture of the teeth occurs to the incisors from falling or stumbling on hard pavements, blows or kicks from other animals.

The molars seldom

ture of incisors

sustain such injuries.

Frac-

usually complicated with considerable con-

tusion and laceration of the

must be removed and the

lip.

lip

The

fractured loose sections

treated according to the char-

acter of the injury.

SPLITTING OF THE MOLARS.

— Fissuring of Definition— A condition Synonym

the molars. peculiar to the molars of her-

bivorous animals consisting of a division of a decayed molar into

two or three

Etiology

plate-like segments.

— Splitting of the teeth

vanced stage of decay. accident.

It is

an incident of the ad-

not a separate entity nor an

Pulpitis, alveolar periostitis

and the subsequent

necrosis following these inflammatory conditions, deprive the tooth of

its

nutrition and moisture, and the resulting

desiccation, predisposed

tooth, favors splitting

disease process.

and fissuring as

of the

a termination of the

In the long process of decay which the

molar teeth undergo, final ejection of

by the "layer arrangement"

splitting

the tooth from

the incident preceding the

its

cavity

— self-extraction.

Fissuring limited to the buccal or lingual surface of the

crown

in the

absence of any gross lesion

also of

occurrence to the back molars of both arcades. tion

common

This condi-

evidently due to an inadequate union between the

external enamel and dentine of the crown, and greatlv re-

AXl.MAL DHNTIS'IRV.

210

known

scniblcs the abnormality of the incisors

or "ilenuchni^."

harmless condition

as "erosion" in

Ijut

itself,

should be regarded as evidence of a poor quality of teeth.

Anatomy

Pathological

— The

incfdent occurs

fjuently to the superior molars, Init ferior ones.

The

splitting

may extend through greatest

number

may

most

seen also in the

In the

terminates just l)eyon(l the

veolar margin on the lingual side of the tooth, dividing into

two very unequal segments, one

principal part of the tooth,

in-

be limited to the crown or

the entire length of the tooth.

of cases

fre-

alit

which comprises the

and the other

a thin shell consist-

ing of the crusta petrosa and external enamel.

In other instances the tooth

ments

— two lateral

shells

and

broken into three segwhich

a central large one,

in-

cludes the fang and roots. In rare cases a superior molar

divided into

two equal

portions by splitting from table to root between the two layers of the internal enamel.

The

condition

and necrosis from gin,

complicated with considerable osteitis

lateral pressure against the alveolar

and from the decomposition

impacted food.

mar-

In the

old case the opposing tooth will be found elongated and the

tongue and cheek

may

be severely

wounded from

friction

of the protruding segments.

Treatment

— Removal

opposing arcade.

of the

tooth and leveling of the

(See extraction.)

FOREIGN BODIES IN THE MOUTH. Foreign bodies become lodged In the horse and

mestic animals. sticks of

and

the

wood become wedged between

pins, tacks

mouth

ox pieces

i)ig,

the do-

the superior arcades,

and splinters lodge between the

the dog, cat and

all

corncob and

teeth:

pieces of bones are frequently found.

ANIMAL DENTISTRY.

gll

In one case a tack was found firmly lodged in the infiindibii-

lum

of the lateral superior incisor.

Diagnosis

—Attention

attracted to disturbed mastica-

tion, rejection of partially masticated food, disinclination to eat,

ptyalism and later to the fetor caused by pressure necro-

sis,

and the decomposition

Treatment

— Removal

mouth with

tions of the

of food.

of the object followed

solution of borax,

irriga-

alum or boric

acid.

FRACTURE OF THE INFERIOR MAXILLA. Varieties

(i)

Simple fracture of the neck of one ramus.

(2)

Simple fracture of the neck of

(3)

Simple fracture of one ramus along the molar

l)Oth rami.

arcade.

Fracture of the angle without dental complica-

(4)

tions.

(5)

Comminuted

(6)

Fracture near the articulation.

Etiology

— Kicks

fracture along the molar arcade.

from horses sustained as the victim

walking through the stable

aisle is the

of fractures of the inferior maxilla.

and cars and other forms bone.

most common cause

Collisions with vehicles

of violence

seldom fracture

this

Solutions in the continuity of the ramus from bit

gnathitis

an occasional cause (see page 214).

And

finally

too forcible blows on a misdirected punch while repulsing teeth occasionally fractures the jaw. the bite sustained during a fight

In the dog and cat

the chief cause of this

injury.

Symptoms is

— The

by no means

subject

diagnosis of fractured inferior maxilla

a simple

matter under

all

circumstances.

The

usually presented several days after the accident, at

which time the tumefaction

will require differentiation

from

other diseased condition characterized by enlargement of

ANIMAL DENTISTRY.

212

the inferior maxilla.

In the recent

equally difficult owing to the

case

]ial)i]ity of

diai^nosis

tlie

the fracture remain-

ing a suhperiosteal one until displacement occurs from move-

ments

some days

of the jaw,

masked by

tion continues to be

Deformity

later, at

which time the condi-

swelling.

at the angle, crepitation or

fractured ends

felt

mouth

within the

movement

of the

jaw

moved

as the

with the other hand, and the loosening of one or more molars,

wiU confirm

plain

pathognomonic symptoms the nature

remain masked

a diagnosis, but in the al)sence of these

tmtil

Fir;.

of the injury

may

an abscess forms and points to the

146.

Well Healed Comminuted Fracture of the Inferior Maxilla, with Dental Complications.

surface and thereby admits direct palpation

Fracture

of the

neck of one or both rami

the bone

easily recog-

nized by palpation. In addition to the above

phenomena

serious disturbance to mastication. clination to eat during the

food

starvation,

condition lose

will

flesh

always a little

in-

days, but finally, from sheer

the feces.

become emaciated,

The suffer

which

subject will

from

colics

die.

Treatment f(KKl

will

be ingested unmasticated,

be found

rapidly,

and probably

crushed

will

first

there

There

â&#x20AC;&#x201D; The

and

principal treatment consists of feeding

licjuid

food, in order to prevent unnetessary

ANIMAL DENTISTRY.

Appliances to immobolize the fracture are

use of the jaw.

never satisfactorily retained, and

When

213

prove

service.

little

abscesses form their contents are evacuated and the

wound searched

The

comminuted segments.

for

loose teeth

must be extracted. In fracture of both rami near the incisor teeth, in small

animals amputation can be successfully performed.

Prognosis

â&#x20AC;&#x201D; In

young animals even

may

nuted fractures

bone, and the patient

make

a rather tardy

permanent tumefaction

siderable

the bad fracture

near the neck

severe commi-

always

fatal.

new

recovery with conIn old animals

of the jaw.

Fractures of one ramus

not serious and will reunite with but

deformity and only slight interference health.

the

reunite by an extensive deposit of

with

little

general

the

Fractures without dental complication are less

seri-

ous than those involving the molar teeth.

FRACTURES OF THE PREMAXILLA AND PERIOR MAXILLA. Although the premaxilla is

remarkably

rare.

The

an exposed bone,

superior branch

fractured from a kick, and the incisor teeth.

The

body from

superior maxillary

fracture

occasionally

its

SU-

upon the

fall

frequently frac-

tured conjointly with the other facial bones as a result of kicks or other of the usual forms of violence. the

fixed

articulations

these

bones

promptly and without much deformity.

Owing

fractures

recover

Crushing of the

maxillary spine leaves a somewhat unsightly blemish, but

otherwise these lesions are not serious.

DISLOCATION OF THE TEMPORO-MAXILLARY ARTICULATION. Etiology nivora.

â&#x20AC;&#x201D;This

dislocation

possible only in the car-

In the herbivora the arrangement of the condyle and

ANIMAL DENTISTRY.

214

coronoid process prevents luxation. while masticating bones, or

Anatomy

Pathological

one

in all

dislocation

luxations

all

occurs

yawning.

— The

instances and like

dog

In the

forward

accompanied with

considerable injury to the binding and secretory ligaments. It

Symptoms be closed

The jaw

Treatment

will

the pathogno-

be locked open and cannot

In the unilateral luxation the jaw

1)y force.

turned to one

be unilateral.

— Inability to close the mouth

monic symptom.

but

may

usually bilateral, but

—A

open

side.

piece of hard

wood two

feet

long and

about one-half inch thick, wide enough to rest along both mferior arcades,

mouth)

the

adjusted teriorly.

l^y

firmly fastened to the lower

wrapping with strong cord.

jaw (within

The

stick thus

then used as a lever to depress the jaw pos-

When

sufficient pressure

condyle snaps into

its

brought to bear the

cavity.

BIT GNATHITIS.

— Bit contusions. Fractured jaw. Bit sores. —A traumatic inflammation of the interdental

Synonyms Definition

space of the low^er jaw^ produced by bruising with the

Etiology

— Bit gnathitis

especially curb bits. ally

The

produce the trouble

upon

reins in the

hands

caused by the use of harsh

to control

condition

bits,

straight or snaffle bit will occasionin

horses inclined to "pull" heavily

of a

powerful reinsman.

"pullers" are the susceptible subjects,

made

bit.

them by the use

Habitual

when attempts

of harsh

riggings.

are

The

seen most frequently in the coach horse, saddle

horse, hunter and polo ponies, and in the light harness horse that

difficult to control.

Pathological

Anatomy

— The lesion consists of an intense

local stomatitis, periostitis

ously.

and

osteitis

occurring simultane-

The indammatory action may be confined

to a small

ANIMAL DENTISTRY.

215

circumscribed area at the very edge of the jaw, or extend

Tbe process

across the entire ramus to the inferior border.

subsides by the separation of the bone from the soft sur-

rounding structures, and by the exfoliation

of a

sequestrum

the size of which will vary with the extent and severity of the

Complete division

pre-existing inflammation.

ramus

of the

may result in the extremely aggravated forms. Symptoms Tenderness manifested in adjusting

â&#x20AC;&#x201D;

the

bit,

ptyalism, side reining and disinclination to "take" the bit are

prominent symptoms.

Palpation and inspection of the inter-

dental space will reveal a

The abrasion

mucous membrane.

in the

usually large enough to expose the edge of

the jaw, which

the

wound

easily felt with the finger.

mucous membrane may remain

of a small almost imperceptible

with a bistoury,

will reveal

In other cases

intact with the exception

opening which,

enlarged

the bare jaw beneath.

In the

may

be con-

early stage, before the abscess points, there

siderable swelling externally across the ramus, giving

appearance of an external trauma. the process, the bare bone

removed.

wound

With

this

tlie

In the advanced state of

found to be loose and easily

event the process terminates and the

heals rapidly, but leaves a tenderness of the "seat of

the bit" for several months.

Treatment

â&#x20AC;&#x201D; Bit

gnathitis

must be treated on the ex-

pectant plan until the exfoliating process until the

rowing

sequestrum

of pus

well loosened.

in the

prevent the bur-

as well as to hurry the exfoliation,

be exposed by a free longitudinal

The

incision

lifted

removal

then kept free from food by daily is

sufiiciently loosened to

with a small lever or curette. of the

sequestrum

the wound.

Undue

haste

harmful by retarding the

About five days the sequestrum the bottom of the wound

final closure of

may

irrigations until the sequestrum

be easily

complete, that

downward,

the edge of the jaw incision.

after is

removal

curetted to

AMMAL

216

DENTISTRY.

remove small roughened projections that might delay the cicatrization.

During the inflammatory period and is

removed

small,

the bit

must not be used,

sequestrum

until the

unless,

when

the w^ound

can be adjusted at a safe distance above.

OSTEOMATA OF THE SUPERIOR MAXILLA. Definition

—A

non-inllammatory tumefaction on the su-

perior maxillary of

young

ward growth

permanent molars.

Etiology

of the

—This

horses, due to obstructed

abnormality occurs chiefly over the fang

of the third superior molar, the last of the

permanent molars,

At the period

having temporary predecessors to erupt. its

down-

eruption, three years old,

ward course blocked

in a

frequently finds

its

down-

wedge-shaped space, between the

second and fourth molars, which occupy fixed positions

The growth

the jaws.

of the tooth in its

blocked position

produces pressure against the skull and a tumor

Anatomy

results.

— Osteoma of the maxilla

non-

inflammatory growth due to a proliferation of bone

cells

Pathological

somewhat is

loosely arranged.

Their macroscopic appearance

that of dense cancellated tissue, unlike the osteophyte of

inflammatory origin.

They

are difTused over the anterior

end of the superior maxilla and are occasionally Differential

—They

Diagnosis

are

bilateral.

differentiated

from

osteo-porosis by the absence of any general symptoms, the

absence of any abnormality

in the

lower jaw and by their

anterior location, and from growth of traumatic origin by the

absence of heat, pain or swelling of the soft tissues;

odontomata by the age

fron:

of the patient.

Symptoms and Treatment

— (See

abnormal

eruptions,

page 1/5).

CARCINOMATA OF THE PALATE.

The

palate of the horse, opposite the

sixth molars,

fourth,

flftli

and

frequently the seat of carcinomatous growths.

ANIMAL DENTISTRY.

They begin by ing

foci,

the appearance of one or

palate and establish

mouth and

They

free

look-

usually perforate the

communication

may

offensive catarrh of the

of origin

through the

They become complicated with an nasal mucosa and with more or less

Fig.

of a

between the

extend backward to the ethmoid

and sphenoid bones and from the point fauces into the pharynx.

bony

In the old cases that are allowed

nasal cavities.

to survive, the process

Effect

more malignant

and gradually invade more and more widely into

the surrounding tissues.

The

217

147.

Carcinoma Beginning

disturbance to the eye.

One

at the Palate of a

case

coming

Young Horse.

to our notice ex-

cavated a large opening externally through the malar and

lachrymal bones and totally destroyed the globe of the eye

The condition is of course incurable and met by recommending the killing of the patient. (Fig

and is

its

appendages.

I47-)

SARCOMATA OF THE MOUTH. Sarcomatous growths frequent occurrence.

in the palate of the

They begin

in the

horse are of

periosteum of the

ANIMAL )ENTISTRY.

218

palate, usually in the religion of the fifth molar,

upward hetween

They

are

first

the teeth and

alonsj;-

and traverse

the alveolar border.

ol)served by the appearance of a (hfifused swell-

ing of the palate extending along the molars and transversely

They extend upward

across the raphe.

into the alveolar

cavities

around two, three, or even four molars, into

sinuses,

and even produce bulging

molars loosen and fingers,

and

their

fall

of the facial bones.

the

The

out or are easily extracted with the

removal

always

followed

by severe

hemorrhage. After the teeth are removed the cavities rapidly fill

with sarcomatous tissue, which will bleed profusely

disturbed by mastication.

The course

of the process

when slow

in the early stages but very rapid after the teeth have be-

Fic. 148.

come in

Sarcoma of

the

Jaw Involving

seriously involved.

the Entire

They occur

Molar Arcade.

as clinical conditions

horses past the age of ten years, but probably escape

notice during the early period of growth.

The

category of incurable diseases.

They belong

the

disease must not be

designated "osteo-sarcoma," a condition

we have never had

the opportunity of seeing in the domestic animals, although its

existence

not doubted.

(See Fig. 148.)

ACTINOMYCOSIS.

— Lumpy jaw. Definition— Actinomycosis Synonym

a chronic infectious disease

due to the actinomyces, characterized by the formation of a

neoplasm

at the seat of infection.

Susceptible Animals

The

disease

— Ox,

sheep, swine, horse and man.

not entirely foreign to any of the domestic

ANIMAL DENTISTRY. or wild herbivora and omnivora, and

experimentally

Etiology

— The

actinomyces saprophyte

has been produced

rodentia and carnivora.

cause of lumpy jaw

219

forage,

the

growth

of the

The organism is a through which medium it gains

infected

tissue.

entrance into the body by inhalation into the air passages

and by ingestion into the digestive dental irregularities and

Eruption of teeth,

tract.

wounds produced by

fibrous forage

produce favorable channels of entrance, hence the frequency of the disease is,

The organism

about the mouth and pharynx.

however, capable of producing

its

pathogenicity

in the

148A.

Fig.

Lumpy Jaw

the

Ox.

where wounds are

nasal cavities, lungs, stomach and liver

not etiological factors.

Affected Organs salivary glands,

rumen, omasum, Diagnosis

— Mouth,

lips,

nostrils,

Schneiderian membrane, velum, pharynx, liver, lungs,

— The

and mammae.

early signs of actinomycosis located in

visible parts of the body, consist of the

wart-like nodes which may,

the size of a pea.

ous center.

tongue, jaws,

when

These nodes contain

formation of one or first

noticed, be only

a calcareous or case-

In the tongue the condition usually remains

unnoticed until the organ has become indurated (wooden tongue).

In the jaw the disease

first

manifested by the

ANIMAL DENTISTRY.

220

appearance of

less diffused

tumefaction of the

l)y rounded exostoses. As the become structures involved more and more by spread-

ing of the diseased process, the head

may assume an

sightly appearance from the enormity of the swelling.

condition

further complicated by dental disorders

Fig.

by tumefaction

of the parotid region

may

manifested

Symptoms

lead a diagnostician to suspect the ex-

Fig.

istence of the disease in

148c.

districts

in the

Ox.

where actinomycosis

prevalent, but a positive diagnosis of

the internal struc-

not possible in the living animal.

Treatment is

and by dysphagia and

Actinomycostic Inferior Maxillary

â&#x20AC;&#x201D; loosen-

Ox.

diagnosed only at the autopsy.

organic disorder

tures

The

Actinomycosis of the lungs and other internal

dyspnoea. structures

in the

In the pharynx the disease

ing of the teeth.

un-

148B.

Actinomycostic Superior Maxillary

tion

in-

(lumpy jaw) or

ferior maxilla soft

more or

the

â&#x20AC;&#x201D; In

most

the operable effectual

line

actinomycotic tumor ablaof

treatment.

further

ANIMAL DENTISTRY.

221

*g^B>^t^,j^

Fig.

149.

Dental Teratoma and Concha! Fistula. 1.

2. 3.

4. 5.

Mouth of the conchal fistula. Bottom of the fistulous tract. Guhernaculum dentis. Bony plates from the temporal 9. The tooth.

External auditory meatus.

Wall of the

Petrous temporal bone.

10.

11.

fistulous tract.

Zygoma. Temporo-maxillary

articulation.

hone.

(Williams),

ANIMAL DENTISTRY.

222

wound may

assure destruction of the organism the surgical

be treated with powdered copper sulphate at intervals of four to five days during

healing

the

tumor on the surface

body

of the

The

process.

injected with a solution

containing some form of iodine.

Lugol's solution, potas-

sium iodide, 2 per cent, or tincture of iodine,

The

may

be used for

Internally potassium iodide will prove bene-

this purpose. ficial.

inoperable

must be extracted and the caustic

loose teeth

treatment applied to the entire diseased area when possible.

DENTAL TERATOMATA. Synonyms

— Dentigerous

cysts,

dental

mastoid

cysts,

fistulac.

Definition

— An abnormality of early embryonic origin

two teeth develop on the temporal bones near

^vhich one or

the base of the ear.

It is a

but occurs occasionally 'Etiology

— The cause

common

abnormality of solipeds

other mammals. of dental

teratomata

found

aberration of the embryonic evolution of the teeth, guttural

pouch and external

mechanism

which

cated as to be susceptible to variations.

The

car, the

closely allied to conchal fistula, with which

so compli-

condition

frecjuentlv

associated.

Symptoms exist

— Dental

from the time of

tion until maturity, of a fistulous

margin

although they

may

escape detec-

lliey appear at the surface

the form

of the conchal cartilage, discharging a limited cjuan-

mucoid

They

which may

presence.

When

The channel is lined with membrane continuous with the

secretion.

organized epithelial

skin at the orifice. ditions

birth,

mastoid region

opening below the base of the ear or along- the

tity of a viscid

a well

teratomata of the

are susceptible to pathological con-

for the first time direct attention to their

they become infected the resulting

osteitis.

ANIMAL DENTISTRY. and

periostitis

dentitis

character into a

its

becomes

augment

fetid,

the discharge, and

223

change

purulent secretion, and the region

painful to the touch.

When

opened by

incision the cyst

found to contain a

tooth or two, which vary from the size of a hazel nut to that

The

of a full sized molar.

smaller

ones are quite round,

Fig. 150.

Two

Teeth Removed from the Squamous Temporal Bone of a Clydesdale Mare.

while the larger ones assume the typical tooth dimensions.

Treatment

â&#x20AC;&#x201D; The

patient

placed in the lateral recum-

bent position, preferably under the influences of an anaesthetic,

liberal incision

made over

expose the hard object within. be

a tooth.

When

the tumefaction so as to

This will always be found to

a part projects

can be extracted with

ANIMAL DENTISTRY.

224

an ordinary ing's will

\\ olf tootli foccps,

require chiseling- to

When removed

the cavity

second tooth, and

loosen

first

from

must be searched

the canal

the entire lining

fistula,

but frcc|uently the surround-

is long-,

its

cavity.

for a possible

as in the case of conchal

must be resected

to prevent a per-

petual discharge.

DENTAL FISTULAE. Definition

—A

fistulous

related to the

tract

ex-

teeth,

tending from within the mouth to the outer surface of the jaw.

Etiology

— Dental

fistulae result

from the outward point-

ing of an abcess accompanying a decayed molar. trance channel

may

The

be the infundibula or alveolar perios-

In the upper jaw they are occasionally caused by

teum.

defective of the

gums admitting food

second or third molar,

along- the in

external surface

the grooves between the

prominent longitudinal ridges which exist on these

and

en-

the lower jaw they

external violence. to remain

And

may

teeth,

instances result from

in rare

again, sequestra of bones allowed

between the alveolar plates

after the repulsion of

may produce a chronic fistulous opening. Pathological Anatomy In addition to the

teeth

—

companying tula

apex

lesions

ac-

decayed molar (see page 152) the dental

fis-

nothing more than a tract through the bone from the

of the tooth to the surface of the jaw.

Symptoms

—They are seen most frequently on the lower

jaw opposite the apex sixth molars.

of the second, third, fourth, fifth

and

In the upper jaw the second and third molars

are the teeth usually responsible for the condition.

They

appear as small openings, always near the border of the jaw,

which discharg-e a limited amount of pus. the skin

drawn inward by the process

jaw around the ofi^cnding molar

In the old case

of cicatrization.

The

thickened to a perceptible

ANIMAL DENTISTRY. extent.

The

diagnosis

dental arcade.

When

225

confirmed by an examination of the

the tract

direct a small probe

may

be passed from the external opening to the mouth, but ordin-

FlG.

Inferior

arily

Molar Responsible

comes

I50A.

for a Fistula of the

Jaw

in a 7- Year-Old

Horse.

pursues a tortuous course through the bone and

to the surface at a point

more or

less

remote from the

affected tooth.

Treatmentâ&#x20AC;&#x201D; The treatment

of the dental fistula should

ANIMAL DliXTlSTRV.

226

be limited to the extraction of the offenchng niokir with

first

the forceps. skull

four weeks the tract

If after

around the

plate

well curetted alonq-

openins:^

exists the

still

trephined and the tract

course into the alveolar cavity.

its

TRAUMATIC STOMATITIS. Definition

— Stomatitis

mucous membrane Etiology disease of

of the

— Primary,

inflammation

signifies

the

common

seen

the most

traumatic stomatitis

the domestic animals.

all

mouth.

aggravated forms from

the

It is

accidental

ingestion

irri-

tants and from the administration of irritating medicines.

Among

the other causes are dental irregularities, severe bits,

traction on the tongue and the prehension of sharp objects.

But

these instances the inflammation

of a circumscribed

rather than a diffused character.

The mucosa of herbivora wounding by masticating coarse

Beards of cereals

food.

however, occasionally penetrate through terior portion

the

mouth

stomatitis simultaneously in a

cause

and

against

protected

well

around the an-

produce

number

will,

alarming

of animals before the

discovered.

Pathological

Anatomy

promptly terminating

—A

simple inflammatory process Purulent, catarrhal or

in resolution.

necrotic inflammations of the

mouth

The

are rare.

severity

and extent depend, therefore, upon the trauma.

Symptoms

— Ptyalism, champing the jaws, disturbed pre-

hension and mastication and principal

symptoms.

The mucous membrane

the touch and the patient

inspection there

desquamation

Treatment

will

a disinclination to eat are the

will

sensitive to

resent examinations.

redness

and

the severe case

of the superior surface of the tongue.

— Stomatitis

not a serious disease.

of the cause, the administration of soft diet,

Removal

and demulcent

ANIMAL DENTISTRY. or mild, astringent solutions,

ment.

mouth wash

useful

227

the only necessary treat-

for the treatment of either cir-

cumscribed or diffused stomatitis

is:

Alum Sodii boras aa

Spirits gaulthcria

Aqua

q.s.

480

et sig.

Inject

mouth three

the

into

free'y

four

times

daily.

STOMATITIS, INFECTIOUS. Synonyms

— Contagious

pustular

stomatitis;

aphthous

stomatitis; contagious aphtha.

Definition

— An

infectious inflammatory condition of the

buccal mucosa characterized by the formation of a multiplicity of pustules.

Etiology

— Infectious

stomatitis evidently

istence to a specific virus, the identity of

owes

which

its

ex-

unknown.

—

Symptoms Contagious aphtha usually occurs simultaneously in a number of horses belonging to the same stable. Outbreaks often occur which few

of the

first clinical

exia,

which

The virus is the mouth through the medium of cleaning utensils, bridles, etc. The

exposed

evidently carried into

watering places,

at race tracks, fairs or sale stables in

pails,

animals

symptom observed is

escape.

ptyalism and slight anor-

followed by the rapid development of

some cases mouth becomes in-

small pimples which point and leave an ulcer. the skin around the commissures of the

many

fected and leaves behind a depigmentated spot at the seat of

each ulcer.

Treatment

— Infectious stomatitis runs a favorable course

ANIMAL DHXTISTRY

ANIMAL DENTISTRY. in

every case and

requires but

little

229

treatment.

Preventive

measures are the most important and these consist animals

tion of the affected

and

the

of isolaof the

disinfection

infected stalls, implements, feed boxes, etc.

(For a more complete description see works on General Medicine.)

ULCERATIVE GINGIVITIS OF DOGS. Definition

— Ulcerative

gingivitis

carnivorous animals beginning as

gums.

however spreads rapidly

young

a disease of

inflammation of the

to the

surrounding mucosa,

alveolar periosteum and jaw.

Etiology

— The

cause of the disease

undoubtedly the

propagation of microbes which habitually inhabit the mouth of

meat eating animals, and which become pathogenic under Attempts

the influence of a lowered vitality of the animal. to isolate a specific microbe have thus far failed.

Symptoms

— Foetid

with red or bluish red

symptoms. of tartar

The

breath

gums

simultaneously

occurring are

the

first

distinguishing

teeth are found to be coated with an excess

around the gingival margin, and

in the

more ad-

vanced stage they are loosened and easily extracted.

The

gums, cheeks and tongue may become the seat of numerous ulcers as the disease progresses, but often this feature

wanting. in

The process

usually terminates favorably or fatally

from one to two weeks, according to

vitality of the patient, or

long as four to

Treatment

five

— The

its

may become

severity and the

chronic and last as

weeks. first

treatment

should

consist of ex-

tracting the loose teeth and removing, with the curette, of the tartar

washed

from the

stable

ones.

The mouth

freely with mild antiseptics, boric acid

water being the most appropriate ones

all

then

and borax

for the purpose.

50 per cent solution of tincture of iodine painted carefully

ANLMAL DENTISTRY.

230

over the

.e:ums, ulcers

saliva has cess,

and vacant tooth cavities after the

been wiped away

will

frcf|nently arrest the pro-

and would undoubtedly prove

did not prevent

its

a specific

its

toxicity

repetition.

RETENTION CYSTS. Besides the large cyst that occurs

the fraenum of the

tongue (ranula), the mucous membrane of the mouth of horses is occasionally the seat of mucoid cysts varying from the size of a millet seed to that of a pea. location

inferiorly.

fectly

around the commissures, either superiorly or Anatomically they consist of a dilated mucous

resulting from an obstructed outlet.

follicle

The common

They

are per-

benign and yield to evacuation of the contents by

incision.

TUMORS OF THE MUCOUS MEMBRANE OF THE MOUTH. The

following

affecting the

an enumeration of the various tumors

mucous membrane

of the

mouth

(i) Actinomycosis, see page 218.

(2)

Sarcoma, see page 218.

(3)

Carcinoma, see page 217.

(4)

Ranula, see page 250.

(5)

Retention cysts, sec page 230.

LAMPAS. Definition

â&#x20AC;&#x201D;Tumefaction

of the

hard palate just behind

the superior incisor arcade.

Etiology

â&#x20AC;&#x201D; Lampas

a physiological condition occurring

from dental nutrition during the growth of the teeth. occurs at a time wdien the crowns of the teeth are short to overlap the first bars of the palate.

still

too

In old horses

ANIMAL DENTISTRY. the palate

wear

may

project

of the incisors,

Symptoms

beyond the

when

from

level of the arcade

the latter are soft in texture.

—Tumefaction and redness of the

Sensitiveness

the palate.

231

first

bars of

not a characteristic feature.

The

bars project to the level or below the tables of the incisors.

Treatment

—The

impression

popular

lampas

that

inimical to the welfare of an animal necessitates the appli-

cation of efforts to diminish the size of the tumefaction.

This is

done by

scarification

and actual cautery. The

The thermo-cautery

the effectual method.

latter

par excel-

lence the neatest micthod of satisfying the popular prejudice

Confine the horse with the dental halter and

against them.

Pass a round stick through

twitch, and elevate the head.

the interdental space and hold

together with the tongue,

Hold the mouth open by downward pres-

hand.

in the left

it,

sure upon the stick and tongue and keep the upper lip

elevated with the twitch, and then with the right hand cauterize the first

two or three bars

until

they shrink below the

table level.

SECONDARY CHRONIC NASAL CATARRH. Synonyms rhinitis.

— Chronic

Nasal gleet.

nasal

catarrh.

Ozena.

Unilateral

chronic

Purulent accumulations in

the facial sinuses.

Etiology in the

— Primary chronic nasal catarrh

herbivorous animals.

the horse and ox has

its

The chronic

a rare disease

nasal catarrh of

origin in the surrounding structures

and hence can only be described as a secondary condition. The primary lesion can usually be found in the superior dental arcades.

Decayed

teeth, usually the fourth superior

molar, are responsible for 95 per cent of the cases. Alveolonasal fistula, fractures, foreign bodies, parasites, glanders,

tumors and chronic bronchitis constitute the primary lesions of the other five per cent.

ANIMAL DEXTISTRY

232

Pathological

Anatomy

— The

features of a typical case

Purulent or muco-purulent catarrh of the affected

are:

accumulation of the secretions

the recesses of the sinuses,

and bulging

over-filling of the sinuses

side,

of the bones, pressure

necrosis of the turbinated bones and the septa of the sinuses,

outward discharge

of the secretion, alveolar periostitis

and

necrosis of a molar.

Diagnosis

— The pathognomonic symptom

fetid, unilateral

the chronic,

discharge from the nostril occurring simul-

taneously with a dental disorder on the affected

decayed tooth to locate, but

in the early

owing

stage of decay

side.

may be

The

dif^cult

to the frequency of this cause a special

examination of the superior

arcade must be

dental

made

before the other causes are given any consideration. Negative results

from the pa'pation or inspection of the teeth

with or without a mouth speculum

in a

recumbent

and by the

justed,

not sufficient reason

The patient must mouth speculum ad-

decayed tooth as a cause.

to exclude the

be placed

position, a

good

aid of

beginning

light each tooth,

with the fourth, must be carefully examined with a sharp steel pick.

which would

Diseased teeth

escaped notice are

in this

manner found

otherwise

to have one or both

infundibula admitting food into the pulp cavity. teeth have been excluded

the attention

but

no case

may

this

AVhen the

circumspect investigation

be directed to the other possible causes,

of chronic catarrh

teeth be omitted.

may

have

Even

must the examination

be found on one side of the head and

decayed teeth co-exist on both sides Differential Diagnosis

of the

the bilateral catarrhs the lesion in

many

instances

of the head.

— Nasal gleet

differentiated from

glanders by the mallein test; from guttural pouch catarrh

by the profuse discharge during mastication disease

;

in the latter

from bronchitis by the absence of cough and con-

stitutional disturbance,

and by the frothy bubbles usually

ANIMAL DENTISTRY. contained

233

secretion coming- from the lower air passages.

â&#x20AC;&#x201D; The

Treatment

treatment includes:

(i)

Removal

the primary lesion; (2) evacuation of the accumulated secre-

from the sinuses, and, (3) irrigation of the diseased mucous membrane. Internal medication is of little value in tions

terminating nasal catarrh. of

Local applications

in the

form

douches are equally useless.

Fig. 151.

Correct Locations of Openings to Perfectlj' Drain the Sinuses of a Horse's

Head. forating

The upper opening its

drains the frontal sinus outward, and hy per-

floor in the turbinated bone,

The

nasal cavity.

also drains the sinus into the

dotted line on the lower opening shows the direction

to elongate the orifice

when

a tooth

to be repulsed.

OPERATION OF TREPHINING THE SKULL FOR NASAL CATARRH.

â&#x20AC;&#x201D;Two

Equipment

scalpels, three-fourths inch circular tre-

phine, one inch circular trephine, dissecting forceps, chisel, artery forcep, needles and thread teeth are to be repulsed), razor,

and

antiseptics.

(punches and mallet

wadding

of cotton or

oakum

ANIMAL DENTISTRY.

234

Restraint

— Horses

may

be trephined

sition witli the dental halter

be repulsed or

when any

the recumbent position

and twitch.

the stanchnj^ po-

When bone

chiseling- of the

teeth are to is

necessary

essential.

U Fi:;.

i5i.\.

Plain Circular Trephine.

ist

Step

—

Clip,

shave and disinfect the space intervening

between the maxillary spine and longitudinal suture

of the

nasal bones.

2nd Step

— First open the maxillary sinus about one

l''i(,.

1511;.

Assorted Trephines and Tooth

from

its

tremity.

inch

Drills,

with Brace.

external border and one inch from the anterior exl)Ut

vary

the antro-posterior direction according

to tooth to be repulsed.

3rd Step

— Make

with the base of the head.

T-shaped

incision

through the skin

pointing to the median line of the

ANIMAL DENTISTRY 4th Step

— Dissect the

235

muscle and connective tissue from

the bone and arrest the hemorrhage.

5th Step

— Cut a

circular ring in the periosteum slightly

larger than the diameter of the trephine to prevent tearing it

beyond the area 6th Step

of the circle.

— Remove the

skull plate with the three-fourths

inch trephine.

7th Step

—

If a

tooth

to be repulsed, enlarge the open-

FiG. 152.

Surgical Areas of the Sinuses.

A, A.

Maxillary sinuses.

B, B.

Frontal sinuses.

ing toward the median line of the head with chisel and mallet, so that the

punch can be placed on

a straight line

with the tooth.

— (See repulsion of teeth, page 161). 9th Step — Open the skull with the one-inch trephine,

8th Step

point 4 to 5 centimeters obliquely

from the nasal canthus loth Step

— Break

at a

downward and inward

(See Fig. 151.)

down

the thin,

bony septa with the

AXI.MAI. I)K\TIS'rR^'.

236

Ihigcrs so as to freely drain the frontal sinus into the maxil-

and nasal

lary sinus

nth

Step

— Empty and

irrigate the sinuses in the stand-

wad

oakum

ing position and 1

2th Step

cavity.

the openings with

or cotton.

— Suture the transverse incision of the T-shaped

wound, leaving the longitudinal one

for

wadding and drain-

age.

— Irrigate

with 3 per cent zinc sulphate soluPrevent food from entering the cavity by wad-

After-care tion daily.

ding the tooth cavity.

Note

— The

two openings above referred

to are the only

ones necessary to drain the sinuses of the horse's head.

Openings higher up along the purpose.

The important

sinuses

the

bony

septa.

into

the

feature of the operation

nasal

Unless there

frontal sinus serve

cavity by breaking free flow

no useful is

to drain

down

the

from the upper opening

to the nostrils the trephining operation for nasal catarrh

a useless procedure.

CHRONIC PERFORATION OF THE SKULL.

— Under

Definition

this

head we include the openings of

the skull covering the facial sinuses or nasal cavities, that persist after the regenerative process has ceased.

Etiology

— The

chronic or peristent perforations of the

skull of horses follow large surgical

openings necessary to

remove nasal tumors, severe contusions

of the skin compli-

cated with comminuted fractures of the skull plate, attended

with sloughing of the injured area, and circular trephine

openings followed by necrosis of the surrounding bone. The sequel

most

liable to

occur

old horses from the dimin-

ished nutrition of the bone tissue and periosteum.

seldom seen

young animals, except

tion of large dimensions,

area

common

accidental perfora-

accompanied with

integument.

Surgical

loss of a large

perforations,

al-

ANIMAL DENTISTRY. though quite horse but

large, will

may

237

always heal eventually

threaten to

become permanent

in the

young

horses past

The most aggravated forms occur

the age of eighteen years.

from comminuted fractures.

Fjg.

Prof.

Edw.

Cperation

for

153.

Closing

Chronic

Skull

Pcrforatio:-:^.

3rd step of operation.

A. I,

Merillat's

"Melon

slice" resection of the

4th step of operation.

6th step of operation.

Treatment

â&#x20AC;&#x201D; Large

of considerable skin

skin.

See description.

See description. See description.

perforations accompanied with

may

be incurable, but

when

loss

the orifice

ANIMAL 1)KXTISTR\.

?38 IS

of nomin.'il

dimensions

closure

its

lowing operative intervention Step

ist

— Secure

effected

by the

fol-

the subject

the lateral

recumbent

position without anaesthesia.

2nd Step

3rd Step

— Shave the hair from

— (hig. 153A.)

Make

the skin, extending above and

include the orifice within

4th Step — (Fig. 153B.

the surgical area and dis-

mercuric chloride solution 1-500.

infect with

its

153B.)

a "melon-slice" resection of

below the

so as to

orifice,

widest portion.

Make

a longitudinal incision (Fig.

through the skin on each side of and about one

3. 3.)

inch from the orifice, extending the entire length of the re-

sected skin.

5th Step

— Loosen

from the bone

of the skin

all

between

the longitudinal incisions.

6th

Step

wound with

— (Fig.

153C.

Suture

5.)

the

"melon-slice"

interrupted stitches, bringing the raw edges into

'perfect apposition.

— Protect the whole area with clay dressing. After-care — Alaintain perfect protection during eight days 7th Step

and then remove the sutures. the gaping longitudinal

wounds

Apply astringent (Fig. 153C.

4. 4.)

lotions to

which

will

heal by granulations.

APPLICATION OF GUTTA PERCHA PLUGS. An

artificial filling for

the vacant alveolar cavity subse-

quent to the extraction of

r.iolars

indicated

when

the

cavity refuses to close and thereby admits food into the nasal cavities or sinuses, in chronic dento-nasal fistula and in

wadding

a recently

made tooth

cavity that cannot receive

daily attention.

The

filling

suitable

for this

purpose

gutta percha

mixture known to the human dentist as "temporary stop-

ANIMAL DENTISTRY ping."

It is

becomes

hard at the temperature of the body but readily

pliable with heat.

Modus Operandi in

239

hot water and

the cavity to be

— Soften

roll

filled

;

a liberal

amount

of the filling

into an egg-shaped mass, larger than

then, with the aid of a speculum to

open the mouth, force the mass into the cavity to mold to the proper shape

Then remove

and dimensions.

and

trim of¥ the superfluous portion, re-heat and re-adjust to the cavity, leaving

its

exposed end beneath the table

level of

the arcade.

The gutta percha plugs should reach beyond

the alveolar

margin, but not to the bottom of the alveolar cavity, and to prevent disturbance

from mastication the opposing crown

should be removed with the claw-cutter.

When

applied as temporary

filling

after five or six days to clean the

and then be readjusted

secretions,

which time

a tooth cavity

(Fig. loo.)

should be removed

cavity of accumulated for

one week more, at

usually safely

filled.

CRIBBING AND WIND-SUCKING. Definition

identical, the

being an aggravated form of the former.

latter

may

— Cribbing and wind-sucking are

Cribbing

be defined as a pertinacious habit of the horse, charac-

terized

by attempts

defined as the

Etiology

to ingest air, while wind-sucking

same habit

which the attempt

— The actual cause of cribbing

factorily demonstrated.

Idleness and the

may

successful.

yet to be satis-

empty manger are

circumstances generally accepted as favoring the acquire-

ment

of the habit.

Nervousness, gastric indigestion and ob-

scure neuroses, are also mentioned

among

the possible etio-

These assertions are based only upon specuand are doubted most by those who have had the

logical factors. lation,

widest range of observation.

may, however, be safely

ANIMAL DENTISTRY

240

Stated that

llic

habil

or pastime having-

Symptoms

its

one of domestication, a stable habit

some unknown

origin in

â&#x20AC;&#x201D; Grasping

an object with the teeth, contrac-

ting the inferior cervical muscles, istic

grunt consecutively,

cribber.

Some

cause.

and

uttering- the character-

the clinical picture of

subjects follow this

typical

tlie

phenomena by

the de-

glutition of a considerable quantity of air at each attempt, until

marked tympany

Others again succeed

abdomen becomes

of the

apparent.

the deglutition without grasping an

object with the teeth.

Fu;.

The Mouth

Treatment tightly

â&#x20AC;&#x201D; The

strap

place.

stall all

Young

number

will

Cribber.

wide

leather

made

strap

prevent the ingestion of

the attempts at cribbing.

equii)ped with tacks that will prick the throat

the attempt is in

53 A.

application

around the throat

and diminish

of a

air

the

when

the cril)l)ing will cease while the strap

second method consists of removing from the

ol)jects that

can be grasped with the teeth.

The surgical intervention once recommended, consisting of a myotomy of the sterno-maxillary muscle in the upper third of the cer\-ical region, has become obsolete through the revelation of

its

uselessness as a permanent remedy.

ANIMAL DENTISTRY.

The by Mr.

241

pertinacity of the cribbing habit

Des

Plaines,

111.,

was demonstrated

the case of a large

Shetland pony that acquired the habit at the age of three years.

This pony was confined

w^ith the walls inclined at

in a

polished

hardwood cage

an angle of forty-five degrees from

above downwards and outwards, for three

during

years,

which time special care was taken to prevent any contact

At the

with objects that could be touched with the teeth.

end of three years with a manger.

and continued

was experimentally placed

into a stall

In less than ten seconds the cribbing begun

until

returned to the hardwood cage.

HABITUAL PTYALISM.

— Slobbering. Definition— A habit of

Synonym

carriage horses characterized by

an excessive flow of saliva from the mouth while driving.

Etiology

—Habitual ptyalism

by the abnormal curbing

upon the

"pull" heavily

of carriage horses

of the

reins.

neck

The

caused

horses inclined to

position of the head as-

sumed under such circumstances prevents

the free degluti-

tion of the saliva secreted, which in the "pulling horse"

alwa3^s excessive.

riage horse is

Besides, the

mind

of the "pulling" car-

so occupied wMth the bit that no deglutition

attempted.

Ptyalism

wounds,

bit

also caused

gnathitis,

by sensitiveness

and other forms

of the

mouth,

stomatitis, but

these causes "constitute an entirely different entity than that referred to in this paragraph.

Symptoms

— An

excessive flow of saliva while driving in

the absence of any lesion of the

habitual ptyalism. froth,

and

The

mouth determines

secretion

a case of

churned into a stringy

blown by the wind over the harness, horse,

riage and even the coachman.

wards "champing" the

bit

when

There

car-

also a tendency to-

the reins are relaxed.

ANIMAL DENTISTRY.

242

Treatment horses, the ties

â&#x20AC;&#x201D; In

the treatment of

requisite

first

remove

carriage

dental irregulari-

all

that would tend to provoke a flow of saliva by irritating

The

the buccal surface.

Wounds

well rounded.

front of

molars must especially be

the interdental space

The

healed and wolf teeth extracted.

be directed to the bitting. the head chin.

The

attention must then

The bridoon

removed and

reins are placed in the "cheek" or "half-cheek"

rubber cover

to the

must be

checked with an overdraw passing beneath the

loop of the curb a

ptyalism

bit is

or,

the horse cannot be

placed over the

middle or lower bar.

The

l)it

managed

thus,

and the rein attached

bridle

fitted neatly so as

Fin, 154.

The Best

Rit for a Side Pulling Light

to bring the bit to a

molars.

comfortable position near the inferior

"Dropping the

advantage of a

Harness Horse.

bit" a habit of

coachmen

"pulling" horse must be avoided.

And

to gain finally,

by patient "schooling," the horse must be taught to drive with a "light line."

SIDE REINING. Definition

â&#x20AC;&#x201D;A

habit of driving horses consisting of con-

stant inclination to carry the head to one side of the median line of the

Etiology

body.

â&#x20AC;&#x201D; The habit

of side reining

due to an ingenious

attempt to take advantage of the reinsman by placing the

ANIMAL DENTISTRY. head

in a

more advantageous

243

Such

position for leverage.

animals often have serious lesions of the jaws, but these are effects rather

than causes of the habit.

The

habit

acquired by driving an ambitious, prompt horse

often

with

"loafer."

that drives on but one line without pulling

The horse

heavily and shifts gradually to one side of the street belongs In this incident the cause

to an entirelv different class.

Fic.

Fk;. 155-

The

156.

suitable bit to equip witli the flexible

rubber hose.

See

description below.

Fig. 157.

Tongue Lolling A.

Port

Spoon bit. Combined

Bits.

bit.

snaffie

and overcheck

always due to some defect

bit.

the

locomotory

apparatus.

Spavin or other slight painful condition of the hind extremity is

the usual cause of this defect.

Treatment

â&#x20AC;&#x201D;The side reining horse

for defects of the teeth

and lesions

must

first

be treated

of the interdental space.

ANIMAL

244

The

molars must be well rounded to prevent buccal

first

The

wounds.

I)l-:N"riS'lRV.

bit

then kept on a

straig-ht line

by means of washers fastened inside the fortable check

well

mated

used, and the horse

with the jaws

rings.

com-

driven only with one

promptness.

HABITUAL PROTRUSION OF THE TONGUE.

— Tongue Definition — The habit of extending the end of the tongue Synonym

lolling.

from the commissure of the mouth while Etiology

—The habit may be

its

continuation

the tongue

pharynx

due to the

first

acquired

mouth from

to protect an al^-asion of the

driving:.

an attempt

further injury, but

relief to the respirations.

When

dropped from the fauces the lumen of the

increased and the respirations are facilitated suf-

induce a continuation of the habit.

ficiently to

of the tongue, in

which retraction

Paralysis

impossible,

entirely

another condition, occurring as a result of progressive bul-

—a disease. Treatment — Dental irregularities

bar paralysis

fatal

must be corrected and

the head while driving must be elevated with the overdraw

check to bring the

mouth may be

air

When

line.

The

closed with a nose band attached to the bridle.

Attaching the check rubber hose,

passages toward a straight

bit to the

will frequently

these measures

main

bit

by means

of a flexible

prevent the habit.

fail,

amputation of the tongue

the only recourse.

OPERATION OF AMPUTATION OF THE TONGUE. Restraint

— Lateral

recumbent position under chloroform

anaesthesia. ist Step

—

i\Lake

circular

incision,

convexity forward,

from the center of one border to the center of the opposite, so as to

make

one-half of a dove-tail

flap.

ANIMAL DENTISTRY. 2nd Step surface,

—Turn the tongue

and by

upward

245 to expose the lower

complete the inferior half of

a similar incision

the dove-tail.

— Close the wound with interrupted sutures. eight After Care — Feed on soft diet and remove sutures 3rd Step

days.

Amputation

convenience

of the

tongue produces a temporary

prehension of liquids but

in the

in-

otherwise a

The above method leaves

flat

ex-

fault or habit of coach, light-harness

and

harmless operation.

tremity similar to that of a normal tongue.

BIT-LUGGING. Definition

—A

saddle horses, consisting of a constant or periodical tendency to pull heavily

Etiology

upon the

bit.

— Dental irregularities,

cause of the habit,

while never the primary

and render

irritate the seat of the bit

its

cure impossible, by aggravating the animal's temper.

The whip, reinsman

or equestrian recognizes three dis-

tinct

classes of bit-luggers.

that

lugs

from

failure

The

first

the

young horse

understand the nature of the

complicated bitting riggings applied for the

first

time; the

second class comprises the mature horse that has developed the habit

from improper training; and the third class

the

lugger by nature that will "pull to the end of the road" spite of the

punishment

Complications

— Bit

inflicted

by severe

bits.

gnathitis from severe pressure and

lacerations of the buccal surface opposite the

superior molars from

friction of the

enamel points are certain to in

first

and second

cheek against the sharp

result in the lugging horse,

and

turn these injuries, which are frequently of no small pro-

portions, are prone to

—The

Treatment

augment

a bad disposition.

treatment of bit-lugging belongs more

to the domain of that part of horse training known as "bitThe ting" or "mouthing" a horse than that of dentistry.

ANIMAL DENTISTRY.

246 latter

is,

liowcvcr, an essential

proficient teacher of

tlie

horse of (luality will

that the anterior extremities of the all

projections that

may

The always demand

feature of the cure.

irritate

molar arcades be

rid of

the buccal surfaces, as a

prerequisite to the development of the tactile sense of the seat of the sists of

The

bit.

trimming- and

dental operation for this purpose confiling the

anterior molars smooth and

round with the angular cutter and addition, be n^adc to

file.

become gradually accustomed

I5it.s

California

the mouth.

and a

to the

for

Confirmed Luggers.

Iiit.

cnrl),

and

complicated riggings.

dumb-jockey

Fig. 159.

Fig. 158.

The horse must,

port.

the coach and saddle horse the

indispensalde, to develop the sensibility of

should be equipped with a soft

bit

one to one

half inches in diameter to develop the tactile sense

over as large an area as possible, and the elastic reins should

made tighter from day and more accustomed to be

coachmen

to its

day as the horse becomes more

mechanism.

Among

the best

the custom to e(|uip the dumb-jockey with a

ANIMAL DENTISTRY.

247

The Hght harness

straight and snaffle bit on alternate days.

horse

trained to the bit by jogging in the breaking cart

with the simplest possible riggings and

forcible restraint

all

avoided, the aim being to drive the youngster

hand" and teach

''light

upon the

bit.

habitual confirmed lugger that has formed the habit

from the faulty

lessons

first

same manner, and

in the

to respond to the slightest touch

instead of pulling heavily

The

vi^ith

may

be improved by handling

must

in addition careful attention

be given to the w^ounds of the mouth, by attending to the teeth and application of bits that will control the horse and

same time

at the

inflict

no further

example, the covered port

for

protecting the

ment

may

bit

the jaw

sore,

be serviceable by

part and transferring the punish-

to the palate, while

may

curb

wounded

injury.

the palate

sore the straight

be applied, and the lines attached to the lower bar,

the ol)ject point being to prevent the unnecessary aggravation of the horse's disposition.

habitual lugging

over-checking. it

will

may

be palliated considerably by proper

The higher the horse is checked the easier The chin-overdraw is probably the

be to control.

best rigging for this purpose,

mouth

In the light harness horse

owing

kept closed, and that there

irritate the interdental space.

no over-check

will

answer

for

bit to

must,

one horse

prove useless for another, and vice versa.

The confirmed lugger

of the third class

cept by giving plenty of hard in

In this connection

however, be understood that what will

to the fact that the

many

habit

cases

may

abandoned.

work

to lower

incurable ex-

its spirit,

which

impair the animal's health before the In such animals

more than the others

the anterior molars must be free from points to mutilate the inferior molars

soft structures.

Beveling the

gingival margin

backward over the crown

first

from the

to the posterior

border of the table has often been practiced for the purpose

ANIMAL DENTISTRY.

248

from lodging against the teeth, or to

of preventing the bit

prevent grasping the

bit

between them, but

never

eiifectual in palliating the

horse

harmful

molar

The

substance

in that the sensitive dentinal

Extraction of the

in-

first

likewise ineffectual.

veterinarian's

duty ends when

full

all

sharp points

removed from the molars, and when appropriate

are

In the young

lugging habit.

thus exposed to the surface.

ferior

this operation

bits

have been recommended.

FACIAL PARALYSIS. Synonyms— Bell's

Paralysis of the

paralysis.

Par-

lips.

alysis of the seventh cranial nerve.

Definition alysis of the

Etiology

—A

complete unilateral motor par-

partial or

muscles controlled by the seventh cranial nerve.

— Facial

paralysis

caused by injuries to the

mastoid region where the seventh nerve leaves the cranial

The contusion

cavity. in

the recumbent

sustained by hanging in the halter

during surgical restraint or

Symptoms

—The upper

the corner of the lower

mucous membrane, the and

lip is

lip

these

drawn

to the opposite side,

draws inward during

symptoms

When

lip,

inspira-

the paralysis

are less pronounced.

when both

symptoms presented difficulty to retain

par-

Bilateral facial

sides of the

are contused simultaneously from the above causes.

cases the

its

the severe case food will accumulate in the check

paralysis occurs occasionally

either

dis-

dropped so as to show

nostril

from paralysis of the buccinator. tial

floor

in the struggles of painful

from blows.

eases, or

tion

striking the head to the

position,

head

In such

are total inability to

move

food between the teeth and

audible inspirations from vapidity of the nostrils. Differential Diagnosis

— Facial paralysis of

this variety

recognized from that of central origin by the sensibility of

ANIMAL DENTISTRY.

249

the paralyzed region determined by pricking- the parts with a pin.

Treatment

— Removal of the cause,

massage along the course

The

the recovery.

occurs

from

six

liniments, blister and

of the seventh nerve will hasten

return of motion to the parts usually

weeks

to three months.

the injury

was

severe enough to destroy the continuity of the axis cylinders of the nerve the paralysis

may

Fig.

Facial

continue through

life.

i6o.

Paralvsis,

Right Side.

LACERATIONS OF THE

LIPS.

Injuries to the lips are of considerable import in the horse,

owing

to their prehensile

and

of the unsightliness of a

tactile functions,

permanent division

and because of their con-

tinuity.

Etiology

pavement.

— Contact Dog

Treatment of the

with sharp objects.

Falls

on hard

bites.

— The

border of the

labial lip,

wound, which includes

division

requires scrupulous attention in

order to prevent a permanent defect.

Perfect disinfection

ANIMAL DENTISTRY.

250 l)y

prolonged

with weak antiseptic solution

irrimalioti

Hrst necessary

wound

'I'hc

stej).

the

brought together

fn-sl

with mattress or button suture to immobili/cc the edges, and

then closed neatly with interrupted stitches. ing of collodion will

and serve as

thick coat

•

further hold the parts in apposition

still

a protection against injur\-

patient iiuist be fed only

upon

gruel,

and

infection.

The

on the

pillar

tied

rein for at least six days.

RANULA. Definition

—A

cystic tumor, belonging to the class of re-

tention cysts, located

under the

Susceptible Animals

— Dog,

free extremity of the tongue. cat,

ox and man.

Rare

the

horse.

Etiology

— Ranula

generally supposed to be caused by

obstruction of one of the ducts of the sublingual salivary gland.

Diagnosis

— Disturbed

prehension and mastication

;

pal-

pation and inspection.

Treatment to

— Ranula

no treatment except

Evacuation

ammonia,

an obstinate disease and

will yield

total resection of the entire cyst wall.

of the contents

and injections

silver nitrate, etc.,

never

of irritants, iodine,

a lasting success.

ACTINOMYCOSIS OF THE TONGUE. (See i)ages 218-19.)

FOREIGN BODIES IN THE TONGUE. Pins, needles, tacks, spicula of

wood, bones or iron

fre-

quently become lodged deeply into the substance of the

tongue near

its

base.

The

condition

manifested by

dis-

turbed mastication, ptyalism, rejection of partially masticated food and disinclination to eat freely. is

The

penetration

usually well under the base of the tongue at a location

that defies detection Ijy an ordinary palpation or inspection

ANIMAL DENTISTRY. of the

With

mouth.

of the base of the

â&#x20AC;˘

251

mouth specukmi palpation

the aid of a

will reveal a hard, painful area in

tongue

the center of which the penetrating

body

will

be found pro-

truding.

The treatment

body and

free incision across the infected area, followed

consists of removal of the foreign

mild astringent irrigations, alum, borax, sodium chloride, or boric acid solutions.

FROST BITES. Frozen tongues are common

horses having the habit

of protruding the tongue while driving (tongue lolling), and

not infrequently the injury thus sustained will cause necrosis Radical treatment must be de-

of the entire free extremity.

ferred until the extent of the frozen area

by the appearance

Amputation

of a well

becomes apparent

defined line of demarcation.

hasten recovery.

will

LACERATIONS OF THE CHEEKS. Lacerations of the cheek that mutilate or divide the buccinator muscle transversely

ment

to animals

contractility.

by destroying

movements

frequent results.

wounds should Careful

its

of the

permanent

detri-

necessary elasticity and

Constant packing of food

striction to the

are

may prove

jaw

therefore

in the

cheek or

re-

(cicatricial trismus)

evident

that

these

receive intelligent and circumspect attention.

disinfection,

ingenious closure and drainage, and

immobilization of the parts should not be omitted

the

treatment.

TUMORS OF THE

LIPS

AND CHEEKS.

Carcinomata, sarcomata, actinomycosis, warts and retention cysts are the classes of tumors usually found on these organs.

when

first

^n area.

The growths should be promptly removed

observed to prevent their diffusion over too great

Pedunculated warts are removed by surgical abla-

ANIMAL DENTISTRY.

252 tion or lij^ation and

diffused ones by the use of caustics.

tlic

Copper sulphate and arsenic are

man recommends

specific ag^ainst warts.

Quit-

the external and internal use of Fowler's

remedy

solution as a spccil'ic

at^'ainsl

warts coverinj^

a larc^e

Retention cysts usually yield to simple evacuation

surface.

of their contents

a free incision.

Widely spread carcino-

mata and sarcomata arc incurable.

LACERATION OF THE TONGUE. Etiology

mouth

— Traction

the

tone^ue

or administration of medicines

common

the

The body iron work of

examining the

cause

organ sustains

of laceration of the fraenum.

of the

injury from the

the stall or by being

bitten

chain,

tie

by animals

tlie

neighboring

Sudden

stall.

fright

while sleeping with the tongue between the incisor teeth

probable cause of the mysterious lacerations of the

the

tongues of horses.

Symptoms champing

— Ptyalism,

disinclination

of the jaws, rejection of food

and

— Reposition

Treatment

and drink,

the later stages

symptoms.

of severe lacerations, fetor, are the chief

and retention

with sutures and amputation.

eat

of the lacerations

(Operation of amputation see

page 244.) Prognosis well

— The

when sutured

turbed.

tongue

well nourished and will heal

the blood supply

not too greatly dis-

In the horse amputation of the free extremity causes

only tem])OTary inconvenience in the prehension of liquids. In the ox,

dog and

manent impediment

cat loss of the free extremity in

a per-

the prehension of food.

INFLAMMATION OF THE TONGUE.

— — Ingestion

Synonym Etiology

Glossitis.

of irritants,

tating medicaments, bit bruises,

administration of

wounds from

irri-

dental irregu-

ANIMAL DENTISTRY.

Specific inflammations of the

pin punctures, etc.

larities,

tongue are seen

Symptoms

253

actinomycosis and infectious stomatitis.

— Same as lacerations of the tongue. — Removal of the cause; food;

Treatment

soft

mild as-

tringent irrigations; alum, borax, boric acid.

Prognosis

may

— Seldom

Necrosis of the extremity

serious.

require amputation.

ABERRATIONS OF THE FUNCTION OF MASTICATION. The common

aberrations of mastication in animals are

quidding, ejecting, bolting, and wadding of food.

QUIDDING. Definition the food

— Quidding

rolled

refers to that aberration in

and shifted about

finally ejected into the

—

Symptoms This abnormality occurs in forms: (i) From dental irregularities which when attempt is made to masticate, or from

three distinct

produce pain

lesion of the temporo-maxillary articulation.

cases the food in the

(2)

mouth and then

manger.

Etiology and

some

in the

not comminuted, but

mouth and

From

molars

will

which

In these

simply rolled about

ejected in large masses soaked with saliva. dissolution

senile

the

be found irregular, short

molar arcades. in

The

the crowns and fre-

and the food

quently loosened

ejected, as in the

former cases, because the molars are no

their

cavities,

longer capable of performing their function. neurosis affecting the nerves of deglutition. of quidders the

food

ejected into the manger.

quently

finely

The

(3)

will

From

In this variety

comminuted before condition

being

seen most fre-

horses past the age of fifteen years.

Treatment

— The

cording to the cause.

quidding horse must be treated ac-

Sometimes the extraction

of a tooth,

ANIMAL DHXTISTRY.

254

the trimming- of an elongation, or the

filint^

whieh wound the mucous meml)rane,

will

aberration.

cases of senile

orii^in,

enamel points

promptly cure the

loose teeth are ex-

tracted and the elongations are carefull}' hlunted without

The food should be mastication. Ground corn,

further disturhing their implantations. of a character recjuiring but

ground

and bran, given dr}\

oats, cut ha}-

able diet to i)r()long the

In the third

little

life

may

the aberration

fcMMii

the most suit-

of an old animal so afflicted.

often be

For reasons

by withholding hay from the food allowance. difficult

hay

explain,

overcome

foodstuff usually c|uid(lcd.

the

Corn, oats, barley and bran are seldom ejected

in this

form.

In addition, the molars must be well examined to exclude

them

as the cause of the disorder.

EJECTING FOOD.

The

ejection of food, partially or completely masticated,

occurs as a

symptom

of (|uidding,

from causes enumerated

above, and from abnormalities of the mouth or teeth that

produce pain when mastication tooth that

wounds

sarcoma

ate,

attempted.

split

molar

the buccal surface, carcinoma of the pal-

of the jaw,

foreign bodies in the tong-ue or

cheek, and a decaying molar, are

among

the lesions often

responsible for this condition.

BOLTING FOOD. Bolting food refers to the aberration of eating rapidly

and without suf^cient comminution. than a disease, and

The nose-bag method

persistent mastication.

that

the production of the habit, which

augmented by dental disorders colics,

and results

of a habit

often acquired by allowing animals to

become too hungry. prolific in

The

feeding

still

further

that induce animals to avoid

habit causes indigestion and

the loss of no small

found unmasticatcd

of is

the feces.

amounts

of food,

The treatment

ANIMAL DENTISTRY. consists of

255

attending to the molar teeth, and of feeding

first

such a manner as to effectually prevent rapid eating.

Nose-bag feeding should be discontinued.

When

fed in harness the grain. should be spread

upon the ground

over a large surface. out and the grain

In the stable the feed

horses are

box

taken

spread over the entire surface of the

hay manger or upon the

along the front of the

floor

Rapid eating under these circumstances the habit will soon be abandoned.

stall.

impossible and

Specially appointed feed-

ing troughs which allow the food to flow slowly outward as it is

eaten are commendable.

WADDING OF FOOD The accumulation arcades

common

of food

THE CHEEK.

between the cheek and molar

aberration.

a serious dental disorder

It is

â&#x20AC;&#x201D; fissured

caused frequently by

molar, loss of the outer

molar crown, elongation that wounds the cheek,

half of a

The most

etc.

obstinate form of this disorder, however,

due to a defect

buccinator muscle.

in the

be either a partial or complete paralysis,

may which may be

The

defect

either co-existent with a general facial paralysis (see facial paralysis,

page 248) or which may

paralysis of the

when

muscle

circumscribed,

The cause

itself.

of the paralysis,

usually a trauma of the buccinator

branch of the seventh nerve as the masseter.

exist as a circumscribed

lacerated

passes superficially over

wound over

the masseter, that

divides the continuity of the branches of the nerve, liable to

Impactions of food

wounds normal

may

always

be followed by this condition. in

of the buccinator contractility.

the cheek

are

also

caused

muscle which interfere with

trivial surgical or accidental

by its

wound

disturb the function of this highly motile muscle suf-

ficiently

to interfere with

mainder

of the animal's

its

life.

function throughout the re-

And

finally cicatrices of the

ANIMAL DENTISTRY.

256 l)iiccal

mucosa which destroy

injury to

1)C

its

scnsibihty arc

sufficient

followed by this aberration of mastication.

When

due to

hand by correcting the

defect.

The treatment must vary with a dental disorder a cure

the cause.

The cicatricial somewhat by thoroughly beveling the buccal border of the superior molar arcade. The paralytic form is either curable forms are incurable, but can be benefited

or incurable, according to the severity and duration of the injur}'.

INDEX A BERRATIOXS

of the Function of 25."'. Mastication .17.'! Abnormal Eruption of the Teeth. Accidents 160 Acquired Elongation i,f Molars. ... 18r> Actinomycosis 218, 251 Age Determination of 71, 113 74 Ago Birth to One Year

Blood Vessels Blunting of Left

-^*-

— — Age — One Years Age — Two

Two

and

One-half

— Five —Nine

Blunting

First

Superior

108

Right

Molar Bodies in the Mouth Bolting Food

Brachygnathism

r V\NL\ES

Five

^-^

Canine

.18. 51,

.54,

61, 64, 65. 127

Teeth

the

S'.i Eight Years 8!) to Old Age Twenty to Twenty-five Yefsrs..li;5 Age— Old Age li:: Age Routine of Examination to De11.'. termine a Horse's 4S Alveolar Cavity 7."! Alveolar Margin Kcctding cf 152 Alveolar Periostitis Alveolar Plate Removal of Exter107 nal l!l, Alveolo-Dental Periosteum 2 Alveolo-Xasal Fistula 100 244 Amputation of the Tongue 15 Animal Dentistry Scope of Anomalies Artificial 110 Anomalies of the Teeth Natural 117 and Artificial Anorexia 157 Aphtha Contagious 227 Aphthous Stomatitis 227 47 Apical Foramen Application of Gutta I'crcha Plugs. 2:!8 Arcades Inferior 34, 35 Arcades Superior 3:5, 35 Artificial and Natural Anomalies of 117 the Teeth Artificial Anomalies 110

27,

— —

—

107 210 254 179

— Foreign

Ouo-IIalf

Y'ears

Age Age Age

Superior

Molar

and

19 First

—

Horse

28, 30,

Carcinomata Carcinomata of the Palate Caries Caries Dentium

152,

— — —

Catarrh Ctironic and Primary Chronic Nasal 231 Catarrh Persistency of 166 Catarrh Secondary Chronic Nasal.. 231 Champing 241 Character of the Food 119 Cheeks Lacerations of the 251 Cheeks The 130 Cheeks Tumors of the Lips and... 251 Chin Prominent 181 Chin Receding 170 Chronic Nasal Catarrh 231 Chronic Nasal Catarrh Primary and 231 Secondary Chronic Perforation of the Skull. .236 2."{1 Chronic Rhinitis T'nilateral 106 Chronic Sinuses of Lower .T;uv Cement 10, 22

— — — — —

—

Central

— —

Incisors

.40, 51, 52, 54, 56, 00, 63, 64,

Common Enamel Germ Complete Denture of a Horse Contagious Aphtha Contagious I'ustular Stomatitis Contusions Bit Corner Incisors

—

BELI/S

Paralysis 245 Beveling of the Molars 182 Beveling of First lufrrior Left Jlolar

Beveling

Right

Molar Bishoping Bites Frost Bit Contusions

—

Bit Gnathitis Bit Lugging Bit Sores

First

— Polishing the — Shortening of

100

Crowns Crowns

lO.s

Crusta Petrosa

120 251 214 214 245 214

Cupping the Incisor Teeth Cups of the Infundil3ula Cups Renewal of the Cuticle of the Enamel

— Cysts — Dental Cysts — Retention 257

10,

65 47 18 227 227 214

65 239 120 120 22, 23 123 118 120 22 177. 222 230. 251

50, 51, 52, 54, 57. 01. 01.

Cribbing

Inf(M'ior

120

175 251 217 172 172

INDEX.

258

DECAYEI*

Tooth Docayod Tooth

of...l(>i»

rneumonia

DeRhitition

Dental

1712

ir.li,

— Kractmo

Artery

— IIemorrha>;e

107

—

.'?."

—

Denuding Destruction of Temporary Tooth the Permanent Determination of Age Determination of Age Routine

—

EJECTING

174.

Food

17;") .")4

220

Gingivitis of

—

2.54

Elongation of the Molars Acquired 183 Elongation Operation of Cutting. .18G 200 Elongations of the Incisors 44 Embryonic Evolution 21 Enamel 19, 22 Enamel^CnticIe of the 208 Enamel Erosion of the 47 Enamel Germ Common 47 Enamel Organ 187 Enamel Points 187 Enamel Points of Ilerbivora 2(tS, 210 Erosion of the Enamel 117 Eruptions of the Teeth Eruptions of the Tooth Abnormal .. 17.5 Evolution and Retrogression of the 124. 12.5 Teeth Tabulated 44 Evolution Embryonic 5s Evolution of Permanent Teeth 40 Evolution of Temporary Teeth 190 Examination of the Mouth {•Extraction of the Canines of Horses. 172 171 Extraction of the IncisofS

—

Facial

Paralysis Sinuses

cumulations

— Flat

Ac-

231 47 137 209 166 100. 224 222

and Rasp

File

245

— Purulent

Fang

I'issuring of the Molars Fistula Alveolo-Xasal

—

Fistula —Dental

Fistulae— Mastoid Float- The Angular

1.36

Float— The Straight Floating and Filing Floating and Trimming Molars Floating the Teeth of the Ox

130 191 189

202 and Files Methcds of Using on Molars 192 Floats and Float Blades 135. 130

—

I'loats

— —

Foramen l.".."'.

Food— Wadding

113

—

T^ ACIAL

74 of

Diagnosis Dental Digastricus Muscle The 131 Diseases and Irregularities of Teeth. 1.52 Dislocation of the Tomporo-^Iaxillary Articulation 213 Divisions of a Tooth 19 Dog— Denture of.... 30. 40. 41. 42. 43

— Dogs— Ulcerative

.174 159

202

liy

Dog Speculums Dog Temporary Teeth

'I'eetli

Follicle— Dental Food-Bolting Food Character of the Food Ejecting

210

Examination

Eye

from

the 101 Dental Cysts 177. 2:22 Dental Diapnosis i:5.'{ Dental Kvohition and Ketrofression Applied to Determination of Age Summary of 74 48 Dental Follicle Dental Fistula IGG. 224 Dental Halter 148 Dental Instruments Their Uses 1 47 Dental Papilla Dental Teratomata 222 Dental Tissues Arrangement of in Incisor 24 Dentigerous Cysts 222 Dentinal Substance 47 Dentine 2."i 10. 20, Dentitis l.-)2

—

F.xl Taction of the Teeth of Dogs. Extraction with Forceps

of in

— Apical

48 2.54

119 254 the Cheek.... 225

47 210 250

Month Tongue Temporary and

Foreign Bodies F'oreign Bodies

the in the

Formulae of manent Dentures

Per.\nimals

00. 67 160 Fracture of Decayed Tooth .211 Fracture of the Interior Maxilla. 209 Fracture of the Teeth' 214 Fractured .Taw Fractures of the Premnxilla and 213 Superior Maxilla 251 Frost Bites 127 Functions of the Teeth .

GERM — Common Gingivae Gingival Cushions of

Gingivitis

Dogs

Enamel

— Ulcerative

(Jleet- Nasal Glossiti-s

Gnathitis— Bit Porcha Gutta

Plugs

— Applications

47 19 45 229 231 252 214 2.38

HABPriTAL

Protrusion

the

244 241 130 19

Tongue Habitual

Ptyalism

Hard Palate—The Hard Tissues

llomorrhage from the Dental Artery. 101 100 Palatine 18 Horse Complete Denture of 49 Horse— Temporary Teeth of

Hemorrhage

—

INCISOR

—

Nippers

Incisor Teeth of the Ox.

.37.

143 51

INDEX.

— —

Incisor Teeth Sheddinpr of 175 Shortening Incisor Teeth 123, 206 Teeth -Polishing, Cupping Incisor 123 and Staining the IS, 127 Incisors Incisors Central

—

— Incisors — Corner Incisors — Elongation Incisors — Extraction Incisors —

49, 51, 54, 56, 60, 03. 64,

50, 52, 54, 57, 61. 64,

65 206

of of

171 51 64

Inferior

— Intermediate — Lateral 50, 51, 54, Incisors — Permanent of Horse. Incisors — Permanent of Ruminants. Incisors — Temporary of Horse Incisors Incisors

.51,

65 .27, 28 34 50 227 35 34, 51

56, 60, 64.

Infectious Stomatitis Inferior Arcades Inferior Incisors Fracture of the. .211 Inferior Maxilla Inferior Maxillary 129 39 Inferior Molars 32, 33, 34, 38 Inferior Molar of Ox 252 Inflammation of the Tongue

—

Infundibula— The Infundibula Cups of the Infundilmlum Inspection of the Mouth

118 118

—

21 135 Instruments Dental Their Uses ..135 51. 57 Intermediate Incisors Introduction 13 Irregularities and Diseases of Teeth. 152

—

19.

—

T AW— Fractured ^ Jaw — Prominent Jaw

214 181 179

— Receding

T ACERATIONS

of the Cheeks

-'—'

251

259

tions 237 Micro-Organisms 17;! Molar Crown Cutter 144 Molar Cutter Angular 142 Molar Cutter Or Trimmer Closed. 1.".7 13,s Molar Cutter Open Molar Extractor Closed Ill Molar Extractor Open 14 Molar Separator 140 Molar Fourth 54 Molar Natural Cavities of,...:... 23 176 Molar Teeth Molars IS, 30, 127 Molars Acquired Elongation of. ...1S5 209 Molars Fissuring of the Molars Fourth and Fifth.. 62. 04, 65 Sixth ^lolars 63,64, 65 Second and Third Molars First,

— — —

—

— —

— — — — — 65 57, 61, 39 32, Molars — Inferior Molars — Permanent of Ruminants.. 30 184 Molars — Projections on 209 Molars — Splitting of the 32 Molars — Superior Floating and Molars— Trimming 189, 191, 192 135 Mouth — Inspection of the 133 Mouth — Palpation of the 217 Mouth — Sarcomata of the 144, 145, 146 Mouth Speculum 131 Muscle — The Digastricus 64,

50, 54,

—The Mas.seter —The Pterygoid

Muscle Muscle Muscle Muscle Muscle Muscle

—The —The —The —The

33,

34,

30,

31,

130

Externus ...131

Pterygoid Internus ...131 131 Sterno Maxillaris 131 Stylo Maxillaris 131 Temporalis

—

Catarrh Chronic, Primary Chronic and Secondary Chronic

N ASAL

50, 51, 54, 56, 60, 64, 65 Lips and Cheeks Tumors of the... 251 liips 249 Lacerations of the Lips Paralysis of the 245 Lolling Tongue 244 Lugging Bit 245 Lumpy Jaw 218

231 231 Nasal Gleet Natural and Artificial Anomalies of 117 the Teeth i" Neck Necrosis of the Teeth of Herbivora 152, 154 Nerve and Blood Supply of Horses' 25 Teeth 19 Nerves 143 Nippers Incisor 18 Nomenclature of the Teeth

MARGINS

ODONTOMATA

Lacerations of the Lips Lacerations of the Tongue

Lampas Lateral Enamel Projections Lateral Incisors

— —

249 252 230 187

—

— —

of the Teeth Masseter Muscle The Mastication Mechanism of Mastoid Fistulae Maxillary The Inferior Maxillary The Superior Maxillo-Nasal Notch

— — —

Mechanism

—

of IMastication Merillat's (Prol. Ed's) Operation for Closing Chronic Skull I'erfora-

20 130 129 222 127 127 130 129

—

Opening the Skull

17S 164 .186

Operation of Cutting Elongations. Operation of Trimming and FloatISO ing Molars 70 Osteo-Dentine 176 Osteoma of the Maxilla 210 Maxilla Osteomata of Superior 202 Ox Floating Teeth of 51 Ox Temporary Teeth of .

— —

INDEX.

260

231

O7.ona

"P AI.ATR- Carcinomala

— Tho

I'alalc

I'alatine

the... 217

Hard

i:{(t

Ilemorrliairt'

I'alpation of the

— Dental raralysis —

1<'><^

Mouth

i:'.:{

I'apilla

Boll's, Facial, of tho Lips,

of the Seventh Cranial

Nerve. .248 .-. Parrot Mouth 170 182 ParviffnatUism Perforation of the Skull— Chronic. 230 Pericementitis 152 .

Peridentitis

Permanent

Teeth

Incisor

Permanent Permanent Permanent Permanent Permanent

Incisors of Uuminants. Molars of Ruminants ... Teeth Evolution of ... Teeth Number of Tooth IJotrogression of. Persistency of Catarrh IMs Temporary Teeth of .

— — —

—

Polishing the Crowns Polishing Incisor Teeth Poll Strap Predisposing Causes Preface

Prehension Premaxilla Fractures of the Premaxilla The Primary Chronic Nasal Catarrh

—

Prognathism

Projections on the First and Sixth Inferior ]MoIars Projections on Superior Corners

184 .185 Prominent Chin 181 181 Prominent .Taw Habitual. 244 Protrusion of the Tongue .131 Pterygoid Externus Muscle The. Pterygoid Internus Muscle The... 131 241 Ptyalism Habitual 241 Pulling

— — —

—

Pulp

47 153

19, 24,

Pulpitis

152,

Purulent Accumniulatinns in Facial 231 Sinuses .227 Pustular Stomatitis Contagious.

—

/^UIDDING

253

RANULA

250 Receding Chin 179 Receding .Taw 179 Receding of Alveolar Margin 71 Reining Side 242 Remnant Teeth 202 Removal of External Alveolar Plato. 107 Removal of Teeth by Si)lilting witli

—

Chisel Renewal of the Cups Repulsion of Teeth with

251 217 182 134

Sarcomata of the Mouth

Mouiu

Search Light Secondary Chronic Nasal Catarrh. .231 167 Septicaemia Cranial Nerve Paralysis Seventh 248 of 187 Sharp Teeth 175 Shedding of the Incisor Teeth 56 Sheep Temporary Teeth of 120 Shortening of the Crowns Shortening of the Incisor Teeth.... 123 242 Side Reining Sinuses Chronic of Lower .Taw.... 100 Chronic Perforation of the.. 2.36 Skull 104 Skull— Opening the 102 Skull— Trephining the Trephining for Nasal Catarrh2.33 Skull 241 Slobbering 19 Soft Tissues 214 Sores— Bit 209 Splitting of the Molars 123 Staining the Incisor Teeth Sterno Maxillaris Muscle The ....131 Aphthous 227 Stomatitis .227 Contagious Pustular. Stomatitis 227 Stomatitis Infectious Traumatic 226 Stomatiti-s 19 Structures of the Tooth 131 Stylo Maxillaris— The Summary of Dental Evolution and Retrogression Applied to Deter74 mination of Age Fractures of the. 213 Superior Maxilla 33, 35 Superior Arcades 129 Superior Maxillary 32 Superior Molars 30, 31, Superior .Molar Arcade of Ox 38 39 Superior Molar Table of Ox 19 Surfaces of the Teeth 2i)2, 201 Supernumerary Tooth 202 Supplementary Teeth Susceptible Animals 173 .

.34

37 58 05 OS 100 52 120 123 149 173 10 128 213 129

.231 181 Superior .

SARCOMATA Scissor

Horse

—

l.")2

27,

Mallet

Repulsion of the Tooth 105 Restraint 148 23it, 251 Retention Cysts Ri'trogression and Evolution of the Teeth Tabulated 124, 125 Retrogression of the Permanent Teeth 68 68 Retrogression of Temporary Teeth TTnilateral Chronic 231 Rhinitis Routine of Examination of Horse's Mouth to Determine the Age. .113

.170 12(»

—

101

—

TABLE

of Superior Molar of Ox..

Tabulated

Evolution

trogression of Tci'th

and

Re124. 125

208 Tartar Teeth —Abnormal Eruptions of the. .175 Teeth Anomalies of the Natural and Artificial 117

—

Punch and

—

— — —

INDEX. 175 — Canine of Horse —Decayed 172 —Diseases and Irregularities 117 Teeth — Eruption the Teeth — Evolution and Retrogression Tabulated 125 Teeth — Evolution the 44 Teeth — Evolution the Temporary. 49 Teeth — Eye 202 Teeth — Fracture 209 the Teeth — Function the 127 Teeth — Incisor Horse (Per-

Teeth Teeth Teeth

..27,

28,

152,

1.52

124,

of of of

manent

28 39 43 20 Teeth— Molar 18, 30, 127, 176 Teeth Nerve and Blood Supply ( Horses' ) 25 Teeth Nomenclature of the 18 Teeth Number of Permanent 65 Teeth Number of Temporary 65 Teeth Repulsion of 161 Teeth Retrogression of Permanent 68 Teeth Retrogression of Temporary. 68 Teeth Structures of the 19 Teeth Supernumerary 202, 204 Teeth Textures of the 118 Teeth Ulceration of 172 Teeth Wolf 202 Temporalis Muscle The 131 Temporary Teeth Evolution of 49 Temporary Teeth Number of 65 Temporary Teeth Retrogression of. 68 Temporo-Maxillary Articulation Dis27,

)

Teeth of Ruminants 36, 37, 36, Teeth of the Dog .39, 40, 41, 42, Teeth Margins of the .

— — — — — — — — — — — — —

— — — —

location of

—

Teratomata Dental Texture of the Teeth Tie Ropes

—

21.!

222 118 149

261

— —

Tissue Interdental Cancellated .... 48 Tissue Ossifled Connective 48 Tissues Hard 19 Tissues 19 Soft Tongue 130 Tongue Foreign Bodies in 250 Tongue Habitual Protrusion of the. 247 Tongue Inflammation of the 252 Tongue Laceration of 252 Tongue Lolling 244 Tongue Operation of Amputation of the , ... .244 Tooth Divisions oi: a 19

— — — — —

— — —

—

Tooth Chisel The Tooth Repulsion of the

—

Tooth— Self

144 165 153 176 226 162

Extraction of the

Tooth Tumors Traumatic Stomatitis Trephining the Skull Trephining the Skull

for

Xa.sal

Catarrh

233

Trimming and Floating Molars.

... 189

Tumefaction on Superior Maxillary .216 Tumors of the Lips and Cheeks. .. .251

Tumors

of the

the

Mouth

Mucous Membrane

I TLCER.VTIONS of Teeth ^-^ Ulcerative Gingivitis of

Undershot Unilateral Chronic Rhinitis

230 172

Dogs.. 220 181 231

WADDING

of Food in the Check. 255 Warts 251 Wear from Mastication 10

Williams' Operation

Wind Sucking Wolf Teeth Wolf Tooth Forceps Wolf Tooth Separator Wooden Tongue

167 239 202 140 140 219

Vv'ebster i-amiiy Library of Veterinary

Cummings School

of Veterinary Medicine at

Tufts University

200

V\/estboro

North Grafton,

Medicine

Road

MA 01536

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