the third stage of comprehensive treatment

The Third Stage of Comprehensive

Treatment:Finishing

Done by Me :- Dr Wesam AlsaadiSupervision:-

Dr Ahmad AltarawnehDR Raed Alrbata

Dr Nancy Alsarayrah Always Remember to

Keep smiling

Definition

• The Correction of errors made prior to finishing and detailing, over correction

as needed, and settling the case

Finishing Stage

• Finishing Starts at the moment of fitting the appliance and it is part of planed treatment strategy

The American Board of Orthodontics

• ABO has introduced a grading system for models and panoramic radiographs. This is oriented toward occlusal detail

• A measurement instrument has been devised to ensure reliability in measurements.


• Things ABO examine and grade1.Alignment2.2. marginal ridges3.Buccolingual inclination4.Occlusal contacts5.Occlusal relationship6.Overjet7.Interproximal contact8.Root angulation


• In general a case which loses more than 30 points will fail and a case that loses less than 20 points will probably pass .

Finishing Stage • By the end of the second stage of

treatment:- - The teeth should be well aligned - extraction spaces should be closed - Teeth roots should be reasonably parallel - The teeth in the buccal segments should

be in a normal Class I relationship.

Finishing Stage

• In Begg technique, major root movements remained to be done in the 3rd stage

• With contemporary edgewise technique much less treatment remains to be acomplished at finishing stage, because of :-

- The built in features of the preadjusted appliance

- Emphasis on bracket placement

Finishing Stage Most cases require: - Some adjusmtments of tooth position to

get marginal ridges levelled - obtain precise in-out position of teeth

within arches - Overcome any discripancies produced

by errors in either bracket placementor appliance prescription

- Some cases, it is neccessary to alter vertical relationship of incisors too

Aims of Finishing Stage

Enhance AestheticEnhance Individual Tooth Position

within archesEnhance Occlusion Enhance Stability

Aesthetic Aims 1- Extra oral Aims It mainly involve a) correct position of Upper incisors

to APog plane " -1 to 5 mm" b) Lower incisor position in relation

to Apog plane and MP

Aesthetic Aims 2- IntraOral Aims a) Tooth Size Discripancy - It is the 7th key to normal occlusion - As a general rule, 2mm tooth size

discripancy noted from Bolton analysis is the threshold for clinical significance (othman2007)

Tooth Size Discripancy • Managment to this problem could be 1- Reduction of interproximal enamel

(stripping) is the usual strategy to compensate for discrepancies caused by excess tooth size.

* It is more common to be found in Lower teeth , in this case IPR can be carried out in initial stages

* If its in the upper teeth, IPR done in late stage of treatment, other wise it could lead to spacing

Tooth Size Discripancy • Topical Fluoride treatment is always

recommended immediately after stripping is done

Tooth Size Discripancy2- When the problem is tooth size

deficiency, it is necessary to leave space between some teeth, which may or may not ultimately be closed by restorations.

• In case of peg shaped laterals, 2/3 of the space should be distal to lateral and 1/3 mesial. (for best aesthetic, Kokich 2003)

Tooth Size Discripancy• More generalized small deficiencies can be

masked by altering incisor position in any of several ways.

• To a limited extent, torque of the upper incisors can be used to compensate: leaving the incisors slightly more upright makes them take up less room relative to the lower arch and can be used to mask large upper incisors,

• while slightly excessive torque can partially compensate for small upper incisors.

Tooth Size Discripancy

• These adjustments require third-order bends in the finishing archwires. It is also possible to compensate by slightly tipping teeth or by finishing the orthodontic treatment with mildly excessive overbite or overjet, depending on the individual circumstances.

IntraOral Aesthetic Aimsb) Gingival Levels

Four characteristics contribute to ideal gingival form.

1. First, the gingival margins of the two central incisors should be at the same level.

2. Second, the gingival margins of the central incisors should be positioned more apically than the lateral incisors and should be at the same level as the canines.

3. Third, the contour of the labial gingival margins should mimic the cementoenamel junctions of the teeth.

4. Last, there should be a papilla between each tooth

Gingival Level

Gingival Level• The cause of These discrepancies could

be Abrasion of the incisal edges delayed migration of the gingival margins.

• The proper solution for the problem: - orthodontic movement to reposition the

gingival margins or - surgical correction of gingival margin

discrepancies.

Intra Oral Aesthetic Aimsc) Gingival Form1. The presence of a papilla between

the maxillary central incisors is a key aesthetic factor in any individual. Occasionally, adults will have open gingival embrasures or black triangles between their central incisors. These unsightly areas are often difficult to resolve with periodontal therapy.

Gingival Form2. This space is usually due to one of

three causes: a - tooth shape (corrected by IPR or

composite restoration) b - root angulation (corrected by

uprighting) c - or periodontal bone loss (corrected by

orthodontic extrusion to relocate the papillae)

II. ENHANCE INDIVIDUAL TOOTH POSITION WITHIN ARCHES

At the finishing stage of treatment, if the bracket positioning were perfect, such adjustments would be unnecessary.

When the bracket is poorly positioned, usually it is time-efficient to rebond the bracket rather than place compensating bends in archwires


After the bracket is rebonded, a flexible wire must be placed to bring the tooth to the correct position.

Rectangular steel finishing wires are too stiff in bending for tooth positioning.

In the 18-slot appliance, 17 x 25 beta-Ti usually is satisfactory;

in the 22-slot appliance, 21 x 25 M-NiTi often is the best choice, “21 x 25 beta-Ti too stiff in bending”.


Placing bends in the finishing archwire to enhance tooth position should be placed in a flexible full- diminution wire. The next to last wire in the typical sequence

17 x 25 beta-Ti used in 18 – slot appliance21 x 25 M-NiTi used in 22 – slot appliance Any step bends must be repeated in the final wire

that is used for torque adjustments 17 x 25 steel in 18 – slot appliance21 x 25 beta-Ti used in 22 – slot appliance


1. Correct Prominence of Teeth “first order bend”Prominence includes both in-out and rotation According to the American Board of Orthodontics (ABO, 1998) (Kokich 2003).a) In the mandibular anterior sextant, the incisal edges of the mandibular incisors and canines are used to establish proper alignment.

1. CORRECT FIRST ORDER BEND b) In the mandibular

posterior sextants, the buccal cusps of the mandibular premolars and molars are used to determine proper tooth position.

1. CORRECT FIRST ORDER BEND

c) While in the maxillary anterior region, the lingual surfaces of the maxillary incisors and canines are used to assess proper alignment. This surface was choosing because it is the functioning surface of the maxillary anterior teeth, and if these surfaces are aligned properly, the maxillary incisors appear to be in their proper aesthetic relationship


D) In the maxillary posterior sextants, the central grooves of the maxillary premolars and molars are used to assess proper alignment.


Errors in prominence arise from unusual tooth anatomy or poor base adaptation

Correction of these errors can be done by first order bend

Typical Location - mesial to lateral incisor “ inset or step

in bends - canines “ offset , step out bends - First molars “ offset, step out bends”


Methods to correct rotation At initial stages by exaggerated bracket

positioning, partial ligation of aligning AW, piggy back, sectional cantilever spring (Whip), couple moment using elastic, TPA or even HG, open coil spring, or surgical replantation or luxation but with high risk of ankylosis.


For final deroataion and over correction use: •Steiner rotation elastic•Repositioning the bracket•Wire bending•Abrahamian techniques: This involves placing a figure of eight elastomeric ligature over the tie wing which it is desired to move away from the archwire and tying in the other tie wing with a steel ligature.

ABRAHMAIN TECHNIQUE


2. Correct Teeth Angulation and root paralleling “second order bends”.

In contemporary edgewise practice, it has been almost totally abandoned in favor of angulated bracket slots that produce proper root paralleling when a flexible full-dimension rectangular wire is placed

2. CORRECT SECOND ORDER BENDS

Root angulation should be checked using an orthopantomogram once rectangular wires are placed , no need to wait until working stailess steel archwires are in place

This check comes normally around 6 months of treatment, and can be combined with an evaluation of any signs of early root resorption


when some crown angulation need to be corrected second order bends will achieve that.

While its more time effient to do bracket repositioning in earlier stage .

2. CORRECT SECOND ORDER BEND

If a small amount of tipping will occur in some patients during space closure, and therefore some degree of root paralleling at extraction sites often will be necessary

2. CORRECT SECOND ORDER BEND With the 18-slot appliance, the finishing archwire

is either 17 x 22 or 17 x 25 steel.

These wires are flexible enough to engage narrow brackets even if mild tipping has occurred, and the archwire will generate the necessary root paralleling moments.

If a greater degree of tipping has occurred, a more flexible full-dimension rectangular archwire is needed.

To correct more severe tipping, a beta-titanium (beta-Ti) or even a nickel- titanium (M-NiTi) 17 x 25 wire might be needed initially, with a steel archwire used for final expression of torque.


With wider 22-slot brackets on the canines and premolars and with the use of sliding rather than loop mechanics to close extraction sites,

A 21 x 25 beta-Ti wire is the best choice for a finishing archwire under most circumstances

if root positioning is needed, 21 x 25 M-NiTi should be used first.

2. CORRECT SECOND ORDER BENDS A root-paralleling moment is a crown-

separating moment in edgewise technique just as it is in Begg or any other technique.

To Avoid this effect; Either the teeth must be tied together or the entire archwire must be tied back against the molars to prevent spaces from opening.


Not only extraction sites but also maxillary incisors must be protected against this complication. Also tying the maxillary incisors together, which can be done conveniently with a segment of elastomeric chain from the mesial bracket of one upper lateral incisor across to the mesial bracket of the other, is necessary during finishing.


3) Correct Tooth Torque “ third order bend” The overall inclination of the maxillary anterior

teeth is best evaluated with a lateral cephalometric radiograph.

The importance of correct teeth inclination are:

Aesthetic purpose Functional purpose Stability PD health

3. CORRECT THIRD ORDER BEND The errors in the third order bend could be

Known by assessing: The incisal edges of the anterior teeth. If a

discrepancy exists in anterior inclination, the incisal edges of the anterior teeth will not be in the same plane. Even in-setting or offsetting the incisors relative to one another will not correct the problem.

A second criterion to evaluate is the clinical crown length of contralateral teeth. If contralateral teeth are different lengths, the cause could be relative discrepancies in the inclination of contralateral incisors.

3. CORRECT THIRD ORDER BEND

The third criterion to evaluate is root prominence

The fourth and final criterion is best evaluated from an occlusal perspective. When the incisors are viewed from an occlusal perspective, the cingulum of an improperly inclined incisor is more prominent or more visible.


Ligual Root Torque of Incisors If protruding incisors tipped lingually while they

were being retracted, lingual root torque as a finishing procedure maybe required.

lingual root torque is accomplished with an auxiliary appliance that fits over the main or base archwire.

The torquing auxiliary is a "piggyback arch" that contacts the labial surface of the incisors near the gingival margin, creating the necessary couple with a moment arm of 4 to 5 mm


Ligual Root Torque of Incisors These piggyback torquing arches can be used in

edgewise technique in the same way as in Begg technique . Although they come in a number of designs, the basic principle is the same:

the auxiliary arch, bent into a tight circle initially, exerts a force against the roots of the teeth as it is partially straightened out to normal arch form.

3. CORRECT THIRD ORDER BEND Torquing auxiliary

archwires exert their effect when the auxiliary, originally bent in a tight circle as shown, is forced to assume the form of a base archwire over which it will be placed. This tends to distort the base archwire, which therefore should be relatively heavy—at least 18 mil steel.

3. CORRECT THIRD ORDER BEND Ligual Root Torque of Incisors Other method same like the above but include

bending a loops parallel to occlusal plane in 016 or 014ss. This has been described by Sandler in the Art Meets Science course.


Ligual Root Torque of Incisors A torquing force to move the roots

lingually is also, of course, a force to move the crowns labially. For that reason, Class II elastics are likely to be necessary when active lingual root torque is needed during the final stage of Class II treatment

3. CORRECT THIRD ORDER BEND Another method is to use the built in torque

and express it with full dimension AW or adding torque to the wire or sometime inverting the brackets.

Three factors determine the amount of torque that will be expressed by any rectangular archwire in a rectangular slot:

the inclination of the bracket slot relative to the archwire,

the tightness of the fit between the archwire and the bracket.

Torsional stiffness of the wire

3. CORRECT THIRD ORDER BEND With 18-slot appliance, a 17 x 25 steel

archwire has excellent properties in torsion, and torque is entirely feasible

While in 22-slot appliance full dimension steel rectangular wires are far too stiff for effective torque

So with 22 – slot some prescriptions have extra built in torque to compensate for rectangular finishing archwires that will have more clearance

For Full expression of torque built into 22-slot bracket, use 21 x 25 beta-Ti

3. CORRECT THIRD ORDER BEND Torque control is the weakness of the

preadjusted appliance system , and this is related to 3 factors

1. to have a good torque expression , play degree should be of 1mm , and this will make tooth movement difficult

2. to have some sliding of the wire within bracket , we go for smaller size wires, which reduces torque expression effectiveness

3. the upper and lower anterior torque needs of patients vary greatly


To over come this problem specially when it is related to a single tooth “e.g palatally erupted maxillary lateral incisor”

Third order bends of the wire can be done

Using torqueing plier

3. CORRECT THIRD ORDER BEND Buccal root torque of premolars and

molars Zachirson has pointed out that

negative torque “ lingual crown torque” has a negative effect on smile esthetic

To obtain a broader and more pleasing smile, is not to further expand across the premolars” with risk of relapse “ , but to use buccal crown torque so that crowns are uprighted

III. Enhance Occlusion 1) Anteroposterior Correction It is often necessary to consider horizontal

overcorrection of class II and class III cases Overcorrection can be done with class II ,

clsass III elastics and headgear “for ex” .

1) Anteroposterior Correction

After correction has been completed, these methods can be discontinued or worn on a part time

Patient is then observed for a period of 6-8 weeks

If the case appear to be stable , the appliance can be removed

III. Enhance Occlusion 2) Correction Of Vertical Incisor

Relationship A) Excessive overbite Before attempting to correct excess overbite at

the finishing stage of treatment, it is important to carefully assess why the problem exists

particularly to assess two things: the vertical relationship between the maxillary lip and maxillary incisors, and anterior face height

2) Correction Of Vertical Incisor Relationship A) Excessive overbite

If the display of the maxillary incisors on smile is appropriate, it is important to maintain this and make any overbite correction by repositioning the lower incisors.

If display is excessive, intrusion of the upper incisors would be

indicated.

If face height is short, elongating the posterior teeth slightly (the lower posterior teeth) would be acceptable

If face height is long, intrusion of incisors would be needed

2) Correction Of Vertical Incisor Relationship If intrusion is indicated and a rectangular

finishing archwire is already in place, the simplest approach is to cut this archwire distal to the lateral incisors and install an auxiliary intrusion arch.

Remember that when a maxillary auxiliary intrusion arch is used, a stabilizing transpalatal lingual arch may be needed to

maintain control of transverse relationships and prevent excessive distal tipping of the

maxillary molars.

2) Correction Of Vertical Incisor Relationship

If slight elongation of posterior teeth in indicated , step bends in a flexible archwire would be satisfactory

The intermediate archwire before final torquing archwire is the one for imlemintation of these step bends

For 18- slot appliance , 17 x 25 TMA wire For 22-slot appliance , 21 x 25 M-NITI

2) Correction Of Vertical Incisor Relationship B) Anterior Open Bite

It is important to analyze the source of the difficulty if an anterior open bite persists at the finishing stage of treatment,

To Determine what to do :- • The Upper incisor relation to upper lip

should be checked• Anterior face height


Excessive use of inter arch elastic could lead to such an open bite, by extruding molars

Using a triangular Class III elastic, helps to control the open bite tendency. Use of these elastics, lead to elongation of the molars and incisors is acceptable.

2) Correction Of Vertical Incisor Relationship Mild Open bite can be due to excessively

levelled lower arch This condition is managed best by

elongating lower incisors , but not upper . Steps 1.Use flexible lower arch2.Maintain stiffer upper arch3.supplemented with light vertical elastics


If display of the upper incisors is inadequate, elongation of those teeth to close the bite would be indicated, and the same approach with the flexible / stabilizing archwires reversed would be indicated.

Elongation of lower incisors to close moderate AOB is a stable procedure compared to elongation of upper incisors

III. Enhance Occlusion 3) Correction of Midline The common problem at the finishing

stage of treatment is a discrepancy in the midlines of the dental arches.

This can result either from a preexisting midline discrepancy that was not completely resolved at an earlier stage of treatment or an asymmetric closure of spaces within the arch.

Minor midline discrepancies at the finishing stage are no great problem

3) Correction of Midline

it is important to establish as clearly as possible exactly where the discrepancy arises.

dental midlines are a component of functional occlusion

If a dental midline discrepancy results from a skeletal asymmetry, it may be impossible to correct it orthodontically, and treatment decisions will have to be made in the light of camouflage vs. surgical correction


caused only by lateral displacements of maxillary or mandibular teeth accompanied by a mild Class II or Class III relationship on one side.

the midline can be corrected by using asymmetric Class II (or Class III) elastic force.

As a general rule, it is more effective to use Class II or Class III elastics bilaterally with heavier force on one side than to place a unilateral elastic.

3) Correction of Midline a combination of

Class II, Class III, and anterior diagonal elastics are being used, with a rectangular archwire in the lower arch and a round wire in the upper arch, attempting to shift the maxillary arch to the right


Prolonged use of Class II or Class III elastics during the finishing stage of treatment should be avoided.

Problem with anterior diagonal elastic, it may cause lower incisor crowding , ligating these teeth together wil reduce this undesirable side effect

III. Enhance Occlusion 4) Settling of Teeth "arch-bound" phenomenon:- They

found that with fitting wires, it was almost impossible to get every tooth into solid occlusion, although one could come close.

.As a final step in treatment, the teeth should be brought into a solid occlusal relationship without heavy archwires present.This is called Settling

4) Settling of Teeth

Feature of optimal interdigitation: 1. The buccal cusps of the mandibular

premolars and molars should contact the fossae or marginal ridges of the maxillary molars and premolars.

2. The lingual cusps of the maxillary premolars and molars should be in contact with the marginal ridges or fossae of the mandibular premolars and molars.


Methods for Settling the Teeth 1) By replacing the rectangular archwires at the

very end of treatment with light round arches that provide some freedom for movement of the teeth (16 mil in the 18-slot appliance, 16 or 18 mil in the 22-slot appliance) and using light vertical elastics to bring the teeth together. It was the original method for settling, recommended by Tweed in the 1940s. The difficulty with undersized round wires at the end of treatment is that some freedom of movement for settling of posterior teeth is desired, but precise control of anterior teeth is lost as well.

4) Settling of Teeth 2) Using laced posterior vertical elastics after

removing the posterior segments of the archwires.

It should not be used in patients who had major rotations or posterior crossbite. For the majority of patients who had well-aligned posterior teeth from the beginning, however, this is a remarkably simple and effective way to settle the teeth into their final occlusion. These elastics should not remain in place for more than 2 weeks, and 1 week usually is enough to accomplish the desired settling.


Use of laced elastics for settling the teeth into final occlusion at the end of treatment.

The Light elastics can be used either with light round archwires, or (usually preferred) with rectangular segments in the anterior brackets and no wire at all posteriorly.


3) By using a tooth positioner after the bands and brackets have been removed


A positioner is most effective if it is placed immediately on removal of the fixed orthodontic appliance. Normally, it is fabricated by removing the archwires 4 to 6 weeks before the planned removal of the appliance, taking impressions of the teeth and a registration of occlusal relationships, and then resetting the teeth in the laboratory, incorporating the minor changes in position of each tooth necessary to produce appropriate settling

The positioning device is then fabricated by forming an elastic material (formerly rubber, now usually polyurethane) around the repositioned and articulated casts


Asking the patient to wear it as nearly full time as possible for the first 2 days. After that, it can be worn on the usual night-plus-4 hours schedule. The patient is advised to wear the appliance and practice repeated cycles of clenching then relaxation to encourage the desired tooth movements.

IV. ENHANCE STABILITY • At the conclusion of class II or class III

correction, particularly if interarch elastics have been used, the teeth tend to rebound back toward their initial position despite the presence of rectangular archwires

• Rebound is a 1 to 2 mm phenomenon; posturing can lead to 4 to 5 mm relapse, and obviously it is important to detect it and continue treatment to a true correction.

IV. ENHANCE STABILITY

• Relapse after orthodontic treatment has two major causes:

• 1. Continued growth by the patient in an unfavourable pattern: this need an “active retention” takes one of two forms.

• One possibility is to continue extraoral force in conjunction with orthodontic retainers (high-pull headgear at night, for instance, in a patient with a class ii open bite growth pattern).

• The other, which often is more acceptable to the patient, is to use a functional appliance rather than a conventional retainer after the completion of fixed appliance therapy.

IV. ENHANCE STABILITY • 2. Tissue rebound after the release of

orthodontic force. There are two ways to deal with this phenomenon:

• A) Overtreatment, so that any rebound will only bring the teeth back to their proper position,

• B) Adjunctive periodontal surgery to reduce rebound from elastibc fibres in the gingiva.

IV. ENHANCE STABILITY • Adjunctive periodontal surgery• Surgery to section the supracrestal elastic

fibres1.The first method, originally developed by

edwards is called circumferential supracrestal fibrotomy (CSF).

No periodontal pack is necessary, and there is only minor discomfort after the procedure.

IV. ENHANCE STABILITY

• 2. An alternative method is papilla-dividing procedure to make an incision in the centre of each gingival papilla, sparing the margin but separating the papilla from just below the margin to 1 to 2 mm below the height of the bone buccally and lingually

REFRENCES

• CONTEMPORARY ORTHODONTIC, FIFTH EDITION , WILLIAM PROFIT “ CHAPTER 16”

• EXCELLENCE IN ORTHODONTICS 2012, DIVIDE BRINIE, CHAPTER 23

• SYSTEMISED ORTHODONTICS TREATMENT MECHANICS, MCLAGHLIN & BENNET.

• AMERICAN BOARD OF ORTHODONTICS GRADING SYSTEM FOR DENTAL CASTS AND PANORAMIC RADIOGRAPHS 2012

KEY PAPERS

1. KOKICH VG (2003)2. MCLAUGHLIN RP AND BENNETT JC (1991)3. MCLAUGHLIN RP AND BENNETT JC (2003)4. POLING (1999)

THANK YOU ALL

Salam

the third stage of comprehensive treatment

Health & Medicine