FUNCTIONAL EXAMINATION
INDIAN DENTAL ACADEMY Leader in continuing dental education www.indiandentalacademy.com www.indiandentalacademy.com
INTRODUCTION Modern orthodontics is not restricted to static evaluation of the teeth and their supporting structures,but also includes all functional units of the masticatory system (Eschler 1952). Function is the common denominator joining the individual parts of the oro-facial system. Disturbance in one part of this system do not remain isolated but effect the equilibrium of the whole system. www.indiandentalacademy.com
Nowadays, functional examination constitute a considerable part of clinical examination. It is not only significant for the etiologic part of evaluation of the malocclusion but for determining the type of orthodontic treatment indicated. The three most important aspects of orthodontic functional examination are : • EXAMINATION OF THE POSTURAL REST POSITION AND MAXIMUM INTERCUSPATION. • EXAMINATION OF TMJ • EXAMINATION OF OROFACIAL DYSFUNCTIONS.
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EXAMINATION OF THE POSTURAL REST POSITION AND MAXIMUM INTERCUSPATION
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EXAMINATION OF THE RELATIONSHIP – POSTURAL REST POSITION & HABITUAL OCCLUSION The initial task of functional examination is the assessment of mandibular position as determined by the musculature. The position in the adult dentition is generally centric relation.
Centric relation of the mandible is a superior limit position of the condyles in the fossae with the mandible centered and at its most closed position.
Source: JCO Volume 1981 Jan(32 - 51): Functional Occlusion for the Orthodontist. www.indiandentalacademy.com
The movement of the mandible from postural rest to habitual occlusion as of special interest for all functional examination. It consists of 2 components : 1. Hinge (rotary) action 2. Translating (sliding) movement The objective of examination is to assess not only the magnitude and direction of these movements but also the extend of action of each hinge or sliding component. www.indiandentalacademy.com
During closing from the rest position, several maneuvers can occur A. A normal arc can progress into the occlusal position. B. In such a case the condyle action is primarily rotary C. An abnormal and posteriorly deviated path can produce translatory condylar movement. www.indiandentalacademy.com
During the closing maneuver from rest position, 2 phases of movement can be observed 1. The free phase from postural rest to the point of initial premature contact 2. The articular phase from initial contact to the centric or habitual occlusal position
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A slight sliding component (as much as 2mm) is a normal phenomenon. If the pattern is abnormal, the sliding may be caused by neuromuscular abnormalities, disturbances in the interrelationships, or compensations of skeletal discrepancies. The abnormal pattern may combine component from one or more of these causes,therefore differential diagnosis is important for planning. Source: JCO Volume 1984 May(335 - 341): The Influence of Three Types of Positioners on Mandibular Condyle Relationships - EUGENE H. WILLIAMSON, DDS, MS, JACK C. FISH www.indiandentalacademy.com
The regimen for the examination 1.
Determination of the postural rest position
2.
Registration and measurement of the postural rest position.
3.
Evaluation of the relationship of rest position to occlusal position in the following dimensions.
• • •
Saggital Vertical Transverse www.indiandentalacademy.com
Assessment of the postural rest position The rest position of the mandible depends on head and body posture as they are influenced by gravity. For this reason, postural rest position must be determined from a standard head position. The patient is seated upright, preferably with the back unsupported. The head is oriented with the patient looking straight ahead at eye level. Having the patient look directly into mirror helps establish optimal head posture. www.indiandentalacademy.com
In order to determine the postural rest, the patient’s Orofacial musculature must be relaxed. Muscle exercises (e.g..tapping test) can be used to help relax the musculature prior to carrying out the actual examination. When using the “tapping test” the patient is told to relax and the clinician opens and closes the mandible. Should the patient be very tense the musculature can be relaxed with mild electric impulses(e.g..myomonitor).
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Head posture for determining rest position and tapping test
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The space between the teeth, when the mandible is at rest, is referred to as FREEWAY SPACE or INTER OCCLUSAL CLEARENCE.
Source: JCO Volume 1981 Jan(32 - 51): Functional Occlusion for the Orthodontist. www.indiandentalacademy.com
Methods to determine the postural rest position of the mandible 1. 2. 3. 4.
Phonetic exercises Command methods Non-command method Combined method
ď Ž
H Dentofacial orthopedics with functional appliances Thomas m. graber , alexandre G. petrovic
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Phonetic Exercises The patient is told to pronounce certain consonants words repeatedly (e.g.. ‘M’ Mississippi). The mandible returns to the postural resting position 1-2 seconds after the exercise. The patient is instructed not to move the lips or tongue at this time, even while the dentist gently parts the lips to observe the inter occlusal space. www.indiandentalacademy.com
Command Method Usually, having the patient lick the lips and then swallow produces the desired relationship because the mandible returns to postural rest within 2 seconds after the exercise.
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Non- Command Method The patient has no idea of the parameter being examined. Careful observations are made as the patient talks, swallow and turns the head while being questioned on a number of unrelated subjects. While being distracted, the patient relaxes, causing the musculature to relax as well and the mandible reverts to the postural rest position. www.indiandentalacademy.com
Combined Method The combined method usually provides the best reproduction of the postural rest position. The patient performs a prescribed function(e.g.. Swallowing) and then relaxes. After instructing the patient not to move, the clinician gently palpates the submental muscles to assess whether they are relaxed. muscle tone is increased in occlusion and closing maneuvers. www.indiandentalacademy.com
Components affecting the rest position Short Term
Long Term
1. Inconsistency in muscle tonicity 2. Respiration 3. Body Posture 4. Stress 5. TMS dysfunction
1. Attrition 2. Premature loss of teeth 3. Diseases of neuromuscular system
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Registration of the rest position Registration of the mandibular rest position is important in those orthodontic cases where the functional analysis is significant for the treatment planning. Various methods are recommended for producing the best record • Direct intraoral method • Direct extraoral method • Indirect extraoral method www.indiandentalacademy.com
Direct intraoral method In addition to the visual observation, the clinician can perform a direct intraoral procedure by using a plaster tape registration similar to that one sometimes used in prosthodontics. Measurement is difficult, although millimeter calipers can be used to record the interocclusal space in the canine and incisor area. www.indiandentalacademy.com
Direct extraoral method Direct caliper measurement can be made on the patient’s profile measuring the distance from the soft tissue nasion(at the bridge of the nose) to menton (on the lowest curvature of the chin). This measurement is done in both postural rest and habitual occlusion. The difference between the two measurements constitutes the interocclusal clearance. The disadvantage of this procedure are that of the soft tissue reduce reliability and no record of the saggital relationship is produced. www.indiandentalacademy.com
Direct extra oral assessment method enables the examiner to measure the difference between rest position and occlusal position using lower face height to sub-nasale to gnathion or menton. www.indiandentalacademy.com
Indirect extraoral method Cephalomertric registration offers the most uniformly successful results. The clinician takes 2 or 3 lateral cephalograms under identical exposure and patient positioning conditions. The first in postural rest, the second in initial contact and the third in full habitual occlusion.The measurements can be performed on each head film. www.indiandentalacademy.com
The rest position and freeway space can be determined by comparing the radiographs.
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Guiding the mandible into centric relation begins with having the patient recline and directing the chin upwards. Okeson JP: orofacial pains,ed www.indiandentalacademy.com
5,chicago,1995,pp 147-150
Evaluation of Path of closure in Saggital plane Condylar movement from postural rest to occlusion can consist of : • Pure rotational movement(hinge movement) • Hinge and anterior translatory displacement • Hinge and posterior superior translatory displacement www.indiandentalacademy.com
Class II malocclusion 1. In class II malocclusion without functional disturbance the path of closure is straight up and forward with a hinge movement of the condyle in the fossa. These are true class II malocclusion.
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Hinge movement from the rest To occlusal
Position in a functionally class II relationship with path of closure. www.indiandentalacademy.com
2.
In class II malocclusions with functional disturbances a rotary action of the condyle in the fossa from postural rest to occlusion is evident. From initial contact to full occlusion, condyle action is both rotary and translatory up and backward (posterior shift).Thus the movement combines rotary and sliding components. This type of activity is the most common, particularly in cases of excessive overbite. www.indiandentalacademy.com
Posterior translation or sliding into the occlusal position in an abnormal functional pattern with a deviated path of closure
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3.
In class II malocclusion with functional disturbances if the path of closure is up and forward from rest to initial contact(usually in the molar region) , the mandible may be anteriorly displaced from initial contact as the cusp guide the mandible into the forward position, with translatory movements of the condyle down and forward on the posterior slope of the articular eminence. The path of closure appears more up and forward than it is without tooth interference. This malocclusion is more severe than it appears with the teeth in occlusion. However, this variation of path of closure is least frequent for class II malocclusion. www.indiandentalacademy.com
Anterior translation or sliding into the occlusal position in a severe class II malocclusion
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Class III malocclusion Hinge type Condylar function is often associated with class III malocclusion with straight paths of closure. The closing path can be divided into 3 types: • • •
Rotational movement without sliding action Rotational movement anterior sliding action Rotational movement with posterior sliding action www.indiandentalacademy.com
Various functional relationship in class III malocclusion A. Anterior rest position in a severe class III malocclusion B. Posterior rest position in a forced bite type of class III malocclusion (e.g. pseudo 窶田lass III). www.indiandentalacademy.com
TRUE Class III True Class III: It is a skeletal malocclusion showing
Edge to edge relationship or anterior cross bite Narrow upper arch and broad lower arch Crowding in upper teeth and spacing in the lowers Concave profile with prominent chin May show anterior open bite
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• Edge to edge relationship or anterior cross bite
• Concave profile with prominent chin
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Pseudo Class III (Postural or Habitual Class III): It involves the forward movement of the mandible during jaw closure. Causes: • Occlusal prematurities • Premature loss of deciduous posteriors • Enlarged adenoids in children
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Mandibular Prognathism – true and pseudo forced bite In cases of mesiocclusion, an anterior sliding action is not always a symptom of a functional Cl III malocclusion. With this functional diagnosis, the “true forced bite” with its favorable prognosis and the “pseudo forced bite” with its unfavorable prognosis, must be differentiated.
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Pseudo bite The term pseudo bite includes those true skeletal class III malocclusions where due to partial dentoalveolar compensation of the skeletal dysplasia in the anterior region(Labial tipping of the upper and lingual tipping of the lower incisors),the mandible occludes at the end of the closing path by means of an anterior sliding action. If one reconstructs the tipping of the anterior teeth in a pseudo forced bite, these cases have pronounced negative overjet. The dentoalveolar compensation of the skeletal dysplasia which already exists when treatment is started, gently restricts the range of orthodontic treatment possibilities and unlike a true forced bit, indicative www.indiandentalacademy.com of a very unfavorable prognosis.
Pseudo-forced bite relationship with labial tipping of the upper incisor and lingual tipping of the lower incisors. This is a true class III problem with a marked basal sagittal malrelationship. After uprighting of the incisors, the severity of the class III relationship is quite evident. www.indiandentalacademy.com
Evaluation of path of closure in vertical plane Two types of deep overbite can be differentiated: 1. The true deep over bite with a large inter occlusal clearance is caused by infra occlusion of the posterior segments.It often results from a lateral tongue posture or tongue thrust habit. 2. The pseudo deep over bite with a small inter occlusal space has normal eruption of the posterior segment teeth. The bite is combined with over eruption of incisors.
TROUTEN, JAMES C., ENLOW, DONALD H., RABINE, MILTON, PHELPS, ARTHUR E., SWEDLOW, DAVID. 1983: Morphologic Factors in Open Bite and Deep Bite. The Angle Orthodontist: Vol. 53, No. 3, pp. 192–211 www.indiandentalacademy.com
A. True deep overbite with a wide freeway space. B. Pseudo-deep overbite with a small freeway space
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Evaluation of path of closure in transverse plane Two types of cross bite with lateral shifting of Mandibular midline can be differentiated 1. A cross bite in which the midline shift of the mandible can be observed only in the occlusal position. The mandible slides laterally from rest position into a cross bite in occlusion. This is called as “laterocclusion or pseudo cross bite”. 2. A cross bite in which the midline shift are present in both occlusal and postural rest position.This is referred to as “laterognathy.” www.indiandentalacademy.com
• Laterooclusion Skeletal midline shift of mandible can be observed only in occlusal position,in postural rest both midlines are well aligned www.indiandentalacademy.com
• Laterognathy The center of the mandible is not aligned with the facial midline in rest and in occlusion. These dysplasia constitute true neuromuscular or anatomical asymmetry. A lateral cross-bite with laterognathy is termed true cross-bite. The prognosis is unfavorable for causal therapy. www.indiandentalacademy.com
EXAMINATION OF TMJ
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Examination of TMJ and Condylar movement Symptoms of TMJ problems include: • Clicking and Crepitus • Sensitivity in the Condylar region and masticating muscles • Functional disturbances – hypermobility limitation of movement deviation • Radiographic evidence of morphologic and positional abnormalities. www.indiandentalacademy.com
The term temporomandibular joint disorders (TMD) describes a condition characterized by pain in the preauricular area, the temporomandibular joint (TMJ) or the muscles of mastication, by a limitation of the range of mandibular motion, and by the presence of joint sounds during jaw function. 1.In addition, pain on movement and deviation on opening have been considered signs of TMD. 2.Temporomandibular joint sounds have been described as clicking, popping, crepitus, and grating and are the most prevalent of all the signs of TMD. Source: AJO-Volume 1994 Mar (279 - 287): TMJ sound risk factors in children - Keeling, McGorray, Wheeler, and King www.indiandentalacademy.com
The simplified examination of the TMJ area consists of three steps. 1. Auscultation 2. Palpation 3. Functional analysis
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Auscultation • •
A stethoscope is used to check for sign of clicking and crepitus. The examination is performed by having the patient open and close the jaw into full occlusion. If clicking or crepitus is noted, the patient is instructed to bite forward into incision and then repeat the opening and closing movements. These movements are checked for any sounds with the stethoscope. Most often, sounds disappear in the protruded position. www.indiandentalacademy.com
Types of clicking Initial clicking
Retruded condyle in relation to disc
Intermediate clicking
Unevenness of condylar surface in relation to disc
Terminal clicking
Condyle is too far forward with relation to disc
Reciprocal clicking
Incoordination between displacement of condyle and disc www.indiandentalacademy.com
ITEM Reciprocal click
DESCRIPTION Noise made on opening and closing from centric occlusion position that is reproducible on every opening and closing.
Reproducible opening click
Noise with every opening, no noise when closing
Reproducible laterotrusive click only
Noise with every full laterotrusive movement, no noise on opening
Reproducible closing click
Noise with every closing, no noise when opening.
Non reproducible click
Present on opening in laterotrusion but not repeatable
Crepitus (fine)
Fine grating noise suggestive of mild bone-on-bone contact
Crepitus(coarse)
Coarse grating noise suggestive of gross bone-on-bone contact
Popping
Distinctly audible sound on opening.
Source: AJO-Volume www.indiandentalacademy.com 1990 Dec (512 - 515): TMJ sounds - Rinchuse, Abraham, Medwid, and Mortimer.
Palpation The condyle and the fossa are palpated with the index finger during opening and closing maneuvers. The posterior surface can be palpated by inserting the little finger in the auditory meatus. The condyles can thus be checked for tenderness, synchrony of action and coordination of relative position in the fossae. www.indiandentalacademy.com
Palpation of the TMJ. •
Lateral aspect of the joint with the mouth closed.
•
Lateral aspect of the joint during opening and closing.
•
With the mouth fully open, the finger is moved behind the condyle to palate the posterior aspect of the joint.
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The prevalence of TMJ sounds in children determined by palpation/unaided listening has been reported to range from 2.7% to 26.6%. In studies that used a stethoscope, prevalence rates range from 0% to 35.8% In an adult population, TMJ sound prevalence has been described as dependent on the method used with rates increasing to 78% when a stethoscope was used and to 94% when phonographic recordings were made.
Source: AJO-Volume 1994 Mar (279 - 287): TMJ sound risk factors in children - Keeling, McGorray, Wheeler, and King www.indiandentalacademy.com
Functional analysis Dislocation of condyles and discoordination of movement are symptoms of functional disturbance. Functional movements of the mandible and condyle are carefully assessed. The extent of maximum opening is measured between the upper and lower incisors. www.indiandentalacademy.com
Measuring the amount of mandibular opening. A Boley gauge may be used. The distance is normally between 40 and 65 mm.
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Opening and closing movements of the mandible •
The opening and closing movements of the mandible as well as its protrusive, retrusive and lateral excursion are examined as part of the functional analysis • The path taken by the midline of the mandible during maximum mouth opening is observed. Any alteration in opening are recorded. Two types of alteration can occur 1. Deviation 2. Deflection www.indiandentalacademy.com
Deviation is any shift of the jaw midline during opening that disappears with continued opening(a return to midline). Deflection is any shift of the midline to one side that becomes greater with opening and does not disappear at maximum opening(does not return to midline). It is due to restricted movement in one joint www.indiandentalacademy.com
The cause of TMD remains a subject of great controversy and is generally viewed as multifactorial. A few articles have implicated orthodontic treatment as a possible cause of TMD. Ricketts stated that clinical symptoms of joint derangement have been noted as occlusions were changed, and he suggested that the various orthodontic forces provided during therapy may predispose patients to temporomandibular joint problems. Other studies indicate that orthodontic treatment does not lead to increased occurrence of TMD. In a study by Sadowsky and BeGole the status of TM joint function and functional occlusion was evaluated in 75 subjects who received treatment as adolescents 10 to 35 years previously. The findings suggested that in the orthodontically treated group, the prevalence of TMJ signs and symptoms were similar to those of untreated controls. Source: AJO-Volume 1992 Jan ( www.indiandentalacademy.com Study of): signs of TMD - Hirata, Hernandez, and King.
EXAMINATION OF OROFACIAL DYSFUNCTIONS
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Assessment of Orofacial dysfunction • Swallowing • Tongue • Speech • Lips • Respiration www.indiandentalacademy.com
Swallowing In neonates the tongue is relatively large and located in the forward suckling position for nursing. The tip inserts through the anterior gum pads and assists in the anterior lip seal. This tongue position and coincident swallowing are termed infantile or visceral. With eruption of the incisors at around 6 months, the tongue position starts to retract. Over a period of 12 to 18 months, as proprioception causes tongue postural and functional changes, a transitional period ensues. Between 2 to 4 years the functionally balanced , or mature, somatic swallow is seen in normal developmental patterns. www.indiandentalacademy.com
Visceral swallowing can persist well after the fourth year of life, however, and is then considered dysfunctional or abnormal because of its association with certain malocclusive characteristics(e.g. tongue thrusting).
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Various deglutitional patterns. A. visceral suckle swallow in the neonates. B. Persistance of the infantile type of swallowing C. Somatic, or mature, type of swallowing www.indiandentalacademy.com
Normal deglutition In the normal mature swallow, no tongue thrust or constant forward posture occurs. The tip of the tongue is supported on the lingual of the dentoalveolar area; the contraction of the perioral muscles is slight during deglutition, and the teeth are in momentary contact during the swallowing cycle. www.indiandentalacademy.com
Based on the work by Gwynne-Evans (1954), Ballard(1965) the deglutitional cycle may be divided into 4 stages. Stage 1. The anterior third of the superior surface of the tongue is flat or retracted. The food bolus is collected on the flat anterior part of the tongue or in the sublingual area in front of the retracted tongue. The posterior arched part of the dorsum is in contact with the soft palate. The posterior seal is closed; swallowing cannot yet take place. The teeth and lips arewww.indiandentalacademy.com not in contact.
Variations in the first phase of swallowing. A. Collecting phase in front of the tongue tip B. Collecting phase on the dorsum of the tongue. www.indiandentalacademy.com
Stage 2. The soft palate moves in a cranial and posterior direction. The palatolingual and palatopharyngeal seals are now open. The tip of the tongue moves up as the dorsum drops, creating a groove or depression in the middle third and permitting posterior transport of the bolus. Stage 3. The superior constrictor muscle ring in the epipharyngeal wall (known as Passavant’s pad) starts to constrict. The soft palate assumes a triangular form, both tissues together form the palatopharyngeal seal, often reffered to as velopharyngeal seal. With the closing of the nasopharynx the posterior part of the dorsum of the tongue drops more, this allows the bolus of food to pass through the isthmus faucium. www.indiandentalacademy.com
Stage 4. The dorsum of the tongue now moves posteriorly and superiorly as the palatopharyngeal tissues moves down and forward. The tongue pushes against the tensed soft palate, squeezing the residual food bolus out the oropharyngeal area.
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Four stages of the oral phase of swallowing. The changes in tongue position as the food bolus is transported into the oropharynx during the deglutitional cycle. Function of the posterior seal in the four stages(velopharyngeal valving) www.indiandentalacademy.com
Tongue Size: The tongue can be small, long or broad. A long tongue can usually reach the tip of the nose. Macroglossia implies a large tongue. Position: •It may be affected by enlarged tonsils/adenoids •In class III cases, the tongue is broad and low lying and extends over the dental arches. In such cases, the size of the dental arch should not be decreased by further Orthodontic treatment (E.g.:- Extractions) www.indiandentalacademy.com
Normal Tongue Position
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Tongue Movements: • They may be restricted due to ankyloglossia. • Proffit has stated that the resting pressure of the tongue is one of the primary factors in the maintenance of dental equilibrium
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Tongue Thrusting •It is also called as deviated swallow, visceral swallow, and reverse swallow, retained infantile swallow. •Tongue thrust is actually a misnomer as it implies forced forward placement of tongue. However, swallowing is not a learned behaviour but, is integrated and controlled physiologically at subconscious levels. www.indiandentalacademy.com
Tongue Thrusting •According to Proffit and Mason, it is the combination of one or all of the 3 conditions, 1. Forward placement of tongue during swallowing so that tip of tongue contacts the lower lip 2. Inappropriate placement of tongue between or against anterior dentition during speech 3. Forward positioning of tongue at rest so that the tip is against or between the anterior teeth www.indiandentalacademy.com
During rest the position of the anterior teeth has been altered by the forces of the tongue. An anterior open-bite developed www.indiandentalacademy.com
Tongue Thrusting Types (Moyers) Simple A tongue thrust with the teeth together Associated with digital habit.
Complex Tongue thrust with teeth apart
Retained Infantile www.indiandentalacademy.com
Tongue Thrusting •Tongue thrusting results in Contraction of the circumoral musculature,
Separation of the mandibular and maxillary posteriors , Protrusion of tongue between incisors.
Proffit W, Mason R Myofunctional Therapy for tongue thrusting. Background and recommendations J AM Dent. Association 90:403 – 411, 1975 www.indiandentalacademy.com
SPEECH The tongue ,pharynx,velum, palate and teeth play central roles in phonation. In malocclusion with malposed teeth, malposition of the tongue may also occur impairing normal speech. A simple test the dentist may use is to ask patient to count from 1 to 10 or 1 to 20. The dentist watches closely how the tongue and lips adapt to the structures with which they are supposed to articulate and listen to how the consonants sound. Disturbance of resonance, phonation, rate, loudness, pitch and articulation have all been reported in cleft palate patient. Hypernasality and defective articulation are the most predominant speech disturbance, in cleft patients. www.indiandentalacademy.com
Speech difficulties related to malocclusion Speech sound
Related malocclusion
{s}, {z} consonents
Ant. Open bite, large gap between incisors
{t}, {d} Linguoalveolar stops
Irregular incisors, especially lingual position of maxillary incisors
{f}, {v} Laboidental fricatives
Skeletal class III
{Th},{sh},{ch} Linguodental fricatives Voiced or voiceless
Anterior open bite
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Lips Normally the upper and the lower lip touch each other when the jaws are at rest to form a lip seal. The upper lip is 2-3 mm above the incisal edge of the upper central incisor. The lower lip extends up to the incisal third of labial surface of upper anteriors.
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Lips • Based on the lip seal the lips can be classified as, Competent – Lips are in slight contact when the musculature is relaxed
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Lips
• •
Incompetent – They are morphologically short lips which do not form a lip seal in relaxed state.lip seal is achieved only by active contraction of Orbicularis oris and circumoral muscles. (a) Short Upper Lip (b) Short Lower Lip
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Lips Potentially Incompetent – Normal lips that fail to form a lip seal due to protruding upper incisors.
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Lips • Everted / Curled – They are hypertrophic lips with redundant tissue but weak muscular tonicity.
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Lip Projection • According to ideal E-Line relationship (Ricketts – E esthetic line) lower lip should coincide with a line from the nasal tip to anterior chin and upper lip should be 1 mm behind it. • Lip projection is affected by both dental and skeletal protrusion or retrusion. Lip projection is an important factor in facial esthetics and it decreases with ageing. www.indiandentalacademy.com
Lip Projection • Lip prominence can also be evaluated by relating the upper lip to a true vertical line passing through the concavity at the base of upper lip and relating the lower lip to a similar true vertical line passing through a point in the concavity between the lower lip and chin.
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Lip Projection If the lip is forward to the line, it is prominent. If it falls behind the line, it is retrusive. If both the lips are prominent and are separated by more than 3-4 mm, it indicates dento alveolar protrusion.
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Respiration The mode of respiration is examined to establish whether the nasal breathing is impeded or not Following are typical of patients with oronasal respiration. 1. A high palate 2. Persisting “tooth germ position”of upper incisors 3. Narrowness of upper arch 4. Cross bite 5. Poor oral hygiene. Humans may exhibit 3 types of respiration • Nasal • Oral www.indiandentalacademy.com
A number of simple test exist that can be employed to diagnose the mode of respiration. • Mirror test – A double-sided mirror is held between the nose and the mouth. Fogging on nasal side of mirror indicates nasal breathing and fogging on oral side indicates oral breathing. • Cotton Test – A butterfly shaped piece of cotton is placed over the upper lip below the nostrils. If the cotton flutters down, it indicates nasal breathing. • Water Test – Patient fills the mouth with water and retains it for some time. Oral breathers fail to perform this test. • Observation of external nares – The external nares dilate during inspiration for nasal breathers. No change is observed in oral breathers. www.indiandentalacademy.com
Muscle strength testing MUSCLES
FUNCTION
TEST PROCEDURE
LIP-CHEEK
Lip movement and puts pressure on the six anterior teeth
Place thumb and index finger in corners of mouth; while patient holds lips together, tester attempts to pull lips apart
Orbicularis oris Internal fibers External fibers
Contact when teeth “pouch” Attempt to deflate cheeks
Buccinator
Lateral margins compress Tester places index finger the cheek against the buccal straight against the cheek surface of the teeth interiorly as the patient pulls the cheek against the teeth .Tester cannot break if strength is normal tTMJ and craniofacial pain James R. fricton; Richard J. kroening
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Muscle strength testing Muscles TONGUE
Function
Test procedure
Geniohyoid
Elevates tip of the tongue and Hyoid bone
Patient touches tip of the tongue to tester’s finger as tester resists
Stylohyoid
Elevates hyoid bone and base Test procedure same as above of the tongue.
Extrinsic tongue muscles Genioglossal Hypoglossal Styloglossal
Depress,elevate, and laterally deviate the tongue
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To test lateral motion, instruct the patient to move to left; hold against your resistance. Repeat on right. To test protrusion, have the patient push the tongue forward against your finger.To test retraction, hold the patient’s tongue with gauge. As the patient retracts it, the tester attempts to bring it forward.
Muscles strength testing Muscles MASTICATORY
Function
Test procedure
Masseter
Elevates jaw
Resist closing of jaw from a two finger-width opening
Superficial fibers Deep fibers
Protrudes jaw slightly. Retracts jaw slightly.
Not possible
Temporalis Posterior fibers
Elevates jaw. Retracts jaw.
Resist closing of jaw as above
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Muscle strength testing Muscle MASTICATORY
Function
Test procedure
Lateral pterygoid Superior fibers Interior fibers
Inferior belly contracts during translatory motion of protrusion and during rotary motion of early opening. Superior belly relaxes during opening allowing disk to rotate posteriorly on condyle
Resists jaw at end range of lateral motions and protrusions.
Medial pterygoid
Primary motion is jaw elevation and assists lateral and protrusive motions.
Resists jaw at range of lateral motions and protrusions
digasrtic
Pulls mandible back and down. When the hyoid is fixed, it aids in jaw opening. Raises the hyoid bone and base of the tongue and also steadies the hyoid bone
Attempts to pull jaw forward.
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References
tTMJ and craniofacial pain
James R. fricton; Richard J. kroening
Management of TMJ disorders and occlusion Jeffery P. okeson
OOrthodontics Current Principles and Techniques
Thomas Graber , Robert Vanarsdall, Katherine Vig
OOrthodontic diagnosis – Thomas Rakosi HDentofacial orthopedics with functional appliances Thomas m. graber , alexandre G. petrovic
CContemporary Treatment of Dentofacial Deformity
William R. Proffit
Contemporary Orthodontics - William R. Proffit
OOrthodontics Principles and Practice - T.M.Graber
EEnlow DH: Handbook of facial growth 2nd Edition Philadelphia, PA: WB Saunder 1982
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