In Andrew’s Original System: Concerning the 1st order information: There is no antirotation system on any tooth, except a 10° distal offset on upper molars. Concerning the 2nd order information: Teeth of the buccal segments all present a positive angulation, meaning that they all have a mesial crown tip, mostly for the 1 st and 2nd upper molars. www.indiandentalacademy.com
Concerning the 3rd order information: On the upper arch: - The upper incisor only has a 7° torque - The upper canine has a negative torque of –7, equal to the torque of the biscuspids. - The torque if slightly greater on molars. On the Lower arch: - The torque on the buccal segments is progressive from the canines to the 2 nd molars. www.indiandentalacademy.com
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Andrew’s system soon got the reputation of being an “anchorage burning appliance” - - A torque of 7° on central incisors was soon found to be insufficient, since the play between archwire and bracket slot, which wasn’t taken into account, creates important loss of information during retraction stages and hence the amount torque necessary to compensate for the unwanted lingual tipping was clearly greater than 7° www.indiandentalacademy.com
In 1974, Ronold Roth: Based on anticipation of relapse during and after treatment
came up with his fully
programmed universal appliance. Thus he systematically included the information for over correction in all three planes of space. www.indiandentalacademy.com
Concerning the 1st order information: All teeth in the buccal segment – anti rotation system. Upper molars reinforce distal offset from 10° to 14° and lower molars 4° anti-rotation Concerning the 2nd order information : Canine angulation increased to 11° to 13° Maxillary buccal segment lose their mesial tip and are in more anchorage situation. www.indiandentalacademy.com
Concerning 3rd order information: The torque on the upper incisors is increased by 5° - Torque on the upper canines decreased by 5° - Torque is markedly greater on molars. (-14° instead of -9°) On the lower arch : - Torque on the buccal segments stays identical to Andrew’s except for a decrease from 35° to 30° on the second molar which decreases the “rolling effect” (lingual tip) sometimes noticed with Andrews’ torque.www.indiandentalacademy.com
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After Roth, Terrel Root 1981, proposed ‘Level Anchorage’ - Tweed Phylosophy a. Medium or regular anchorage b. Maximum or major anchorage Removed Roth’s anti-rotation system and increase the angulation on the lower molars to 10° www.indiandentalacademy.com
The Mandibular buccal segments are available with two types of anchorage preparation. -“ Regular” anchorage with a -4°,-6° and -10° distal tip respectively on the 2 nd bicuspid, the 1st molar, and the 2nd molar. - “Major” anchorage with a -6 °, -10 ° and -15 ° distal tip respectively on the 2 nd bicuspid, the 1st molar, and the 2nd molar. www.indiandentalacademy.com
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Wick Alexander : Combination of Andrew’s and Roth Hilgers : - Upper incisors have a considerably increased torque. 22° for the central incisor, 14 ° for the lateral incisor. - Upper canine has a 7 ° torque, this creates a transverse differential of 14 ° between canine and biscuspid. www.indiandentalacademy.com
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Bennett and McLaughlin: -Combination of Andrew’s and Roth with few changes - Anti rotation system was removed, all the mesial tip has been removed. -Upper incisors have markedly increased torque of 17 ° and 10 ° and upper canine -7 ° torque. -The torque on the lower incisors increase to www.indiandentalacademy.com
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Ricketts’ Bioprogresive Therapy : -Modification of Andrew’s and Roth -The angulation in buccal segment t is 0° except for mandibular molar with -5° -Upper incisor markedly increased torque 22° for the central, 14° for the lateral -Upper canine has 7° torque www.indiandentalacademy.com
www.indiandentalacademy.com
As Summary -All the above prescriptions globally reflect the treatment philosophy of their different authors. -It will be necessary for the practitioner to complete
the
programme
information to the wire. www.indiandentalacademy.com
by
adding
“Fully Programmed Translation brackets” by Andrew’s - These are three sets of information mixed according to the treatment needs. -The come in 3 sets bearing values of angulation, torque and anti rotation www.indiandentalacademy.com
“Minimum translation brackets�
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“Medium Translation Brackets”
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“Maximum Translation Brackets”
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Incisor torque
Andrews
Roth
Alex Root Benett Hilgers
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Canine Position
Andrews Andrews
Roth Alex
Root
Bennett
Max www.indiandentalacademy.com
Hilgers
Evolution toward facial type This evolution is also taking place in cephalometrics where the notion of mean now tends to be replaced by growth considerations. This corresponds to the need for individualization of information. Since variability in the morphology of the facial skeleton necessarily implies variability in the dento-alveolar compensations. www.indiandentalacademy.com
SYNERGY INFORMATION SYSTEM –
Rocky Mountain Company: This is according to the mechanical requirements depending on facial pattern in the vertical dimension. The inclination of the upper incisors varies from 12 ° to 22 ° from dolichofacial to brachifacial while the angulation remains identical for the normofacial www.indiandentalacademy.com
-On the canines 0째 torque for the dolichofacial and mesofacial and positive torque for the brachifacial. - For dolichofacial torque values are higher on the molars to prepare an anchorage. -Anti rotation values are markedly increased to 12째 on the first molars in mesiofacial and brachyfacial. www.indiandentalacademy.com
“Dolichofacia”
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“Brachyfacial”
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Swing Towards Facial Patterns Normally, the dento-alveolar sysem acts as a buffer between the skeletal bases, and adjusts for the best according to sagittal vertical and transverse discrepancies. Incorporating dental compensations according to skeletal relationships, facial patterns and growth trends www.indiandentalacademy.com
Steiner’s recommended U/L incisor positions relative to line NA & NB and varied according to ANB angle. -10
00 240
10
250
20
230
30
220
40
210
50
200
190
60
70
180
170
80 160
6 7
5
4
230 220
3
1
0
-1
-2
240 250
3.25
2 260
270
280
290
300
310
3.5 3.75
4
4.75 4.25
4.5
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5
5.25
5.5
Cl. III
Cl. I
Cl.II
Cl. III Cl. I Cl. II
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Cl. III Cl. I Cl. II
At the incisor level:
Maxillary deficiency
Normal transverse relationship
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Mandibular deficiency
At the Canine Level
Hypo-maxillia
Normo-transversal
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Hypo-mandibulie
At the Molar level:
Maxillary deficiency
Normal transverse relationship
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Mandibular deficiency
Thus, In the absence of functional anomalies: 1. The dento-alveolar compensations (inclination and angulation) take place in a coherent way, in accordance with every single facial type, determined by skeletal relationships, either established in the three planes. www.indiandentalacademy.com
2. No matter what technique is used, the information (torque and angulation) we apply must also be coherent in the three planes. In the sagittal plane, the inclinations (or torque ) of the incisors must be coordinated with the angulations of the buccal segments in a well balanced dento-alveolar system www.indiandentalacademy.com
•The torque level is high on the incisors, the angulation values in the buccal segments, especially on the canines will be greater. •On the contrary, if the torque level on the incisors is low, the angulations in the buccal segments, especially on the canines, will be smaller. www.indiandentalacademy.com
In a normodivergent skeletal pattern with a Class III tendency on the upper arch, the high torque value comes with a higher positive value of the angulation in the buccal segments from the canine of the second molar. On the lower arch, the lower incisor uprighting of the canines bicuspids and molars. www.indiandentalacademy.com
On
a
normodivergent
Class I skeletal pattern, coherence of 3rd order iformation incisors
on (torque
inclinations)
with
the on the
second order informaiton in the buccal segments (inclinations) www.indiandentalacademy.com
On a normodivergent skeletal pattern
with
a
Class
II
tendency, coherence of the 3rd order
information
incisors
on
(torque
the on
inclinations) with the 2nd order information
in
the
buccal
segments (angulations). www.indiandentalacademy.com
In this case, the high torque level on the incisors doesn’t come
with
a
sufficient
angulation of the buccal segments; this creates a high risk of root approximation.
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Here, the high level of torque on the incisors comes with a sufficient canine angulation but an insufficient angulation of the bicuspids; this creates an occlusal disturbance and a risk of root approximation. www.indiandentalacademy.com
In a normodivergent Class III skeletal pattern, incisor angulations
are
less
pronounced, torque in a buccal segments will be more
pronounced
thus
rather positive. www.indiandentalacademy.com
In a normodivergent Class I skeletal pattern, coherence of
2nd
order
information
incisor
(angulations)
with the 3rd information in the buccal segments (torque or inclinations)
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In a normodivergent class II skeletal pattern, incisor angulations
are
more
pronounced, toruqe in the buccal segments will be less
pronounced
thus
rather negative. www.indiandentalacademy.com
Here, the canine has a positive torque, which is adopted to the transverse skeletal relationships: if the torque on the bicuspids is not coordinated, an occlusal dysharmony is creted. www.indiandentalacademy.com
Class III transversal
Class I transversal
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Class II transversal
“A normal face is no longer one where cephalometric values are closest to the mean, but one whose cephalometric values show harmony in their relationships defined in variable association tables.
In this
concept, there is no such thing as a unique normal face defined by a mean value, there are a series of normal faces� - J. Dibbets. www.indiandentalacademy.com
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