Changing Trends in Preadjusted Edgewise system Dr. Anand Patil

In Andrews 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 1st and 2nd upper molars.

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 2nd molars.

Andrews 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 wasnt 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

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.

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.

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 Andrews except for a decrease from 35 to 30 on the second molar which decreases the rolling effect (lingual tip) sometimes noticed with Andrews torque.

After Roth, Terrel Root 1981, proposed Level Anchorage - Tweed PhylosophyMedium or regular anchorageMaximum or major anchorageRemoved Roths anti-rotation system and increase the angulation on the lower molars to 10

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 2nd bicuspid, the 1st molar, and the 2nd molar. Major anchorage with a -6 , -10 and -15 distal tip respectively on the 2nd bicuspid, the 1st molar, and the 2nd molar.

Wick Alexander : Combination of Andrews and RothHilgers : - 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.

Bennett and McLaughlin: Combination of Andrews 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 6

Ricketts Bioprogresive Therapy :Modification of Andrews and RothThe 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

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 by adding information to the wire.

Fully Programmed Translation brackets by Andrews - 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

Minimum translation brackets

Medium Translation Brackets

Maximum Translation Brackets

Andrews Roth Alex Root Benett HilgersIncisor torque

Andrews Andrews Roth Alex Root Bennett Hilgers MaxCanine Position

Evolution toward facial typeThis 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.

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

On the canines 0 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 12 on the first molars in mesiofacial and brachyfacial.

Dolichofacia

Brachyfacial

Swing Towards Facial PatternsNormally, 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

Steiners recommended U/L incisor positions relative to line NA & NB and varied according to ANB angle.

Cl. III Cl. I Cl.II Cl. III Cl. I Cl. II Cl. III Cl. I Cl. II

Maxillary deficiencyNormal transverse relationshipMandibular deficiencyAt the incisor level:

Hypo-maxilliaNormo-transversalHypo-mandibulieAt the Canine Level

Maxillary deficiencyNormal transverse relationshipMandibular deficiencyAt the Molar level:

Thus, In the absence of functional anomalies: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.

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

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.

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 buccalsegments from the canine of the second molar. On the lower arch, the lower incisor uprighting of the canines bicuspids and molars.

On a normodivergent Class I skeletal pattern, coherence of 3rd order iformation on the incisors (torque on inclinations) with the second order informaiton in the buccal segments (inclinations)

On a normodivergent skeletal pattern with a Class II tendency, coherence of the 3rd order information on the incisors (torque on inclinations) with the 2nd order information in the buccal segments (angulations).

In this case, the high torque level on the incisors doesnt come with a sufficient angulation of the buccal segments; this creates a high risk of root approximation.

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.

In a normodivergent Class III skeletal pattern, incisor angulations are less pronounced, torque in a buccal segments will be more pronounced thus rather positive.

In a normodivergent Class I skeletal pattern, coherence of 2nd order incisor information (angulations) with the 3rd information in the buccal segments (torque or inclinations)

In a normodivergent class II skeletal pattern, incisor angulations are more pronounced, toruqe in the buccal segments will be less pronounced thus rather negative.

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.

Class III transversal Class I transversalClass 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.