lingual orthodontics / orthodontic courses by indian dental academy

INDIAN DENTAL ACADEMY

Leader in continuing dental education www.indiandentalacademy.com

www.indiandentalacademy.com

Seminar by:Dr. Sandhya Anand

Done under the guidance of:Dr. Ashima Valiathan BDS (Pb), DDS, MS (USA)Professor and HeadDirector of postgraduate studiesDept. of Orthodontics and Dentofacial OrthopedicsManipal College of Dental Sciences, Manipal


Contents• Introduction.• Historical perspective.• The lingual appliance.• Diagnosis and treatment planning.• Lingual bracket placement.• Bonding techniques.• Lingual mechanotherapy.• Keys to success in lingual therapy.• Improving patient comfort.• Conclusions.• References. www.indiandentalacademy.com

Aesthetics has always been a catchword among patients. With more number of adult patients desiring orthodontic treatment, special aesthetic demands of the patients pose a great challenge to the orthodontic community. These patients have professional and social commitments and cannot accept ‘visible braces’ even for a short time.

To be able to serve such patients, the orthodontic community came out with the ultimate aesthetic solution – Lingual Orthodontics.


Lingual orthodontics, apart from offering the aesthetic benefit, also provides several mechanical advantages. Since its inception in the 1970s, great advances have been made in this modality.

At present, Lingual orthodontics is a complete system in itself and encompasses accurate diagnosis, treatment protocol, clinical and laboratory procedures.


Historical perspectiveHistorical perspective


As early as the late 1880s, the dental literature extolled the advantages of moving teeth with lingual appliances. These early appliances were removable and designed to expand the dental arches.

• The first reference to lingual mechanics dates back to 1889, when John Farrar introduced the ‘Lingual removable arch’.

• In 1918, Dr. John Mershon published a paper entitled "The Removable Lingual Arch as an Appliance for the Treatment of Malocclusion of the Teeth".


• In March 1942, Dr. Oren Oliver introduced the labiolingual appliance.

• In the mid-'50s, Dr. William Wilson demonstrated a labio-loop-lingual appliance that was a forerunner of the Wilson modular appliance system.

• The Crozat appliance, conventional acrylic removable appliances, Nance buttons, trans-palatal arches and lingual attachments were the results of efforts of clinicians to use the mechanical advantage of lingual aspect of teeth to bring about desired tooth movement.


However, all these appliances were used as a supplement to labial mechanics, with no cosmetic incentive.

With the advent of orthodontic bracket bonding in the early 1970s, the possibility of a fixed lingual appliance occurred to several orthodontists working independently.


• In 1975, Dr. Craven Kurz1975, Dr. Craven Kurz of Beverly Hills, California created his own lingual appliances by modifying labial edgewise appliances, and utilized them on a limited basis in his practice. He limited his treatment to the mandibular arch for fear that the forces of occlusion would dislodge brackets placed on the lingual surface of the maxillary anterior teeth.


• Later in 1976, Dr. Kurz submitted specific designs and concepts to the U.S. Patent Office for the patent rights to his unique edgewise lingual appliance. He joined with Ormco Corporation (Orange, CA) to develop and produce a prototype of this appliance.

• Among the unique features of this appliance were a bite plane incorporated in the maxillary anterior brackets, mesh bonding pads designed to adapt to the lingual surface of the teeth, and pre-torqued archwire slots based on a conversion of commonly used labial torque values. www.indiandentalacademy.com

• In December 1979, Dr. Kinya Fujita1979, Dr. Kinya Fujita, of Kanagawa Dental University, Japan, published an article describing appliances with a lingual bracket design and mushroom shaped archwires.

• His work confirmed the experiences of Dr. Kurz and Ormco that, certainly with refinements, lingual appliances were a viable adjunct to the orthodontist's armamentarium.


• In December 1980, Ormco decided to put together a team of orthodontists (the Task Force ) to study the appliance further and make suggestions regarding improvements.

• The Task Force consisted of:i. Dr. C. Moody Alexanderii. Dr. Richard (Wick) Alexanderiii. Dr. John Gormaniv. Dr. James Hilgersv. Dr. Craven Kurzvi. Dr. Robert Scholz vii. Dr. John (Bob) Smith.


• The Task Force was initially charged with the responsibilities of evaluating the appliance design over a two-year period.

• Their specific objectives were:1. To help refine bracket design (dimensions,

torques, angulations, thickness, etc.).2. To develop mechanotherapy techniques.3. To create archwire designs.4. To discuss treatment sequences. 5. To determine case selection criteria.


The Lingual ApplianceThe Lingual Appliance


• In 1976, the Ist generation of lingual brackets were produced by Ormco.

• The Ist generation brackets or First Kurz Appliance had an .018" slot size for conservation of incisal-gingival bracket dimension and for compatibility with existing archwires.

Development by Kurz & co-Development by Kurz & co-workersworkers


• The incisal wing of the maxillary incisor brackets incorporated a bite plane which served the dual purpose of assisting in opening deep bites and redirecting the forces of occlusion to prevent shearing of the bond.

• As a result, bond failure was dramatically lower than before.

• The brackets were bonded according to reciprocal tip and torque values to Andrew’s published values.


The lingual appliance most widely used today is the generation VII appliance, developed in 1990 by Ormco Corp.

• The VIIth generation brackets are much refined, low profile, patient friendly brackets.

• They have a horizontal slot, and are offered in either an 0.018" or 0.022" slot size.

• The premolar brackets have increased width to allow better angulation and rotation control.


Modifications in lingual bracket design.www.indiandentalacademy.com

• Multiple molar attachments are available, including a tube, a twin bracket and a hinge cap or terminal sheath (a convertible bracket that can function as a tube or a self-ligating slot).

• All brackets have a gingival ball hook which facilitates elastic ligature placement, rotation control and placement of intra- and inter-maxillary elastics.


Roll cap bracket on first molar.


• The bite plane on the maxillary anterior brackets is heart-shaped. It is parallel to the archwire and occlusal plane.

Significance: The bite plane allows placement of all brackets during initial bonding even in cases with severe deep bites. The patient’s occlusion is located on the bite planes of the anterior brackets.


Typical lingual appliancewww.indiandentalacademy.com

The bite planes cause immediate disclusion of

the posterior teeth, removing the forces of occlusion from the biomechanical formula. Thus, the correction of crossbites, deepbites, rotations and space closure can be achieved at an accelerated pace without the interference of occlusion.

At the same time, anchorage loss, bowing of the buccal segment, loss of arch coordination and extrusion of molars are made easier without the controlling effect of the forces of occlusion.


• Interbracket distances are reversed with the lingual appliance.

There is less interbracket distance in the anterior, but in the posterior region, the interbracket distances are increased mesio-distally.

This can hinder full bracket engagement in the anterior and reduces the relative stiffness of the archwire in the posterior segment.


Interbracket width is reduced on the lingual.www.indiandentalacademy.com

Wide buccolingual dimension makes lingual bracket placement difficult.

Short interbracket span in lingual treatment.


• The brackets have a custom pad that is fabricated in the laboratory. This ensures proper bracket placement and maximizes bond strength by minimizing the space between bracket and tooth.

This pad makes each lingual bracket unique and gives the orthodontist the ability to prescribe specific tooth movement for each patient.


• The ideal archwire has a mushroom shape. This is due to the large constriction in arch width that occurs as one proceeds distally from the lingual surface of the canine to the bicuspid. Since the brackets are designed to minimize bracket profiles, it is necessary to place compensating first order bends interproximally at the cuspid-bicuspid and bicuspid-molar locations.


Mushroom shaped archwirewww.indiandentalacademy.com

• In cases with short clinical crowns, or if there is a problem with incisal clearance, a second order bend, or step-down, may also be needed between cuspids and bicuspids.


Fujita’s lingual bracket system

(AJO 1979) Kinya Fujita’sKinya Fujita’s purpose for lingual bracket

system, apart from aesthetics, was to prevent injury with labial brackets during sports.

• The first Fujita lingual bracket was introduced in 1979.

• It featured a slot that opened toward the occlusal. The occlusal approach makes arch wire insertion, seating, and removal easier than arch wire insertion with lingually opening slots.


A. Lingual insertion. B. Occlusal insertion.www.indiandentalacademy.com

• A lock pin was inserted mesiodistally into a groove in the slot to secure the archwire, in conjunction with a conventional elastomeric or steel ligature.

• Auxiliary groove was set in the occluso-gingival direction to facilitate correction of the mesio-distal tipping of the teeth.


The presently available Fujita system is still based on an occlusal slot opening, but has multiple slots.

• Brackets for the anterior teeth and premolars now have three slots: occlusal, lingual, and vertical.

• Molar brackets have five slots: one occlusal, two lingual, and two vertical.

• Each of the three types of archwire slots provides different capabilities for efficient tooth movements.


Fujita lingual brackets (OS = occlusal slot; LS = lingual slot; VS = vertical slot;

OW = occlusal wing; GW = gingival wing).www.indiandentalacademy.com

• The basic purpose of incorporating multiple slots is to use Tandem wire mechanics.

This entails use of multiple wires in different

slots to bring about desired tooth movements without side effects.


• The Fujita system is advantageous:

i. In cases in which esthetic considerations are important.

ii. In cases in which the patient is engaged in sports activities (less trauma to the lips).

iii. In undertaking minor tooth movement as a preliminary to prosthodontic treatment.

iv. For orthodontic treatment and fixation as treatment for periodontal disease.

v. Because it makes use of the lingual-bracket and mushroom-arch appliance in lieu of a retaining appliance.


Begg’s lingual brackets

(JCO1982)• Dr. Stephen PaigeDr. Stephen Paige introduced the Lingual

Light Wire technique in 1982.

• Initially, he used the Begg’s TP 256-500 labial brackets.


• The bracket currently used in the Begg system is the Unipoint combination bracket (Unitek), with the slot oriented in the occlusal-incisal direction.

• The Unipoint bracket has a gingival "wing" to place elastic modules on continuous elastic chains.

The Unipoint Bracketwww.indiandentalacademy.com

• Molar Tube Design: Oval tube with a

mesiogingival hook. The squashed oval

tube has some advantages in that it increases patient comfort, allows molar control, and will accept a ribbon arch. Oval Tube


Mushroom arches with horizontal loops for elastics.

• Archwires: The general shape

of the archwires resembles the mushroom shape as proposed by Fujita, except that when use of elastics to the archwire is required, a horizontal loop has been added distal to the cuspids.


Creekmore’s Lingual System (AJODO 1989)

• Described by Thomas Thomas Creekmore in Creekmore in 1989.1989.

• The foundation of the design is the opening of the arch wire slots to the occlusal aspect rather than to the lingual aspect.


Unitwin bracket-centered arch wire slot.

• Conceal brackets are designed around the Unitwin bracket "centered slot" concept.

• The Unitwin bracket is, in effect, a single bracket without tie wings in the center of a 0.045 inch twin bracket.

• It uses the advantages of both single and twin brackets by allowing maximum interbracket distance for optimal tip and torque functions, while providing twin tie wings for rotation control.www.indiandentalacademy.com

• Each Conceal bracket has three different slot widths for the three different functions of tip (A-B), torque (E-F) and rotation (C-F or E-D).


• A critical breakthrough was the design of premolar and molar brackets, with occlusal tie wings projecting mesially and distally instead of labiolingually.


Straight Wire Lingual Brackets

(JCO 2001)• Takemoto and Scuzzo in 2001Takemoto and Scuzzo in 2001 found that the

bucco-lingual distances at the gingival margins do not vary substantially. This led them to conclude that straight archwires could be used in lingual orthodontics if they were placed as close to the gingival margin as possible.

• Compared to other lingual brackets, archwire insertion in this design is from the top instead of the bottom.


• Advantages:- Flossing is easier as the archwire is farther from

the lingual surface and incisal edge.- Mesio-distal with of the bracket is smaller,

allowing adequate inter-bracket distances.- Less composite is needed to raise the bite, since

the brackets are placed more gingivally.- Rotations can be more easily accomplished as

the archwire can be tied tightly to the bottom of bracket slots.


- Torque control is improved.- Rebonding is easier as the archwire does not

have to be removed.- Pre-formed archwires can be used with a few

additional bends, reducing chairtime and allowing the use of sliding mechanics.


Self-ligating Lingual Brackets

(JCO 2002)

• First described by Macchi et al in 2002Macchi et al in 2002, the Philippe Self Ligating Lingual Brackets (Forestadent, St. Louis, MO) can be bonded directly to the lingual tooth surfaces.

• Since they do not have slots, only first- and second-order movements are possible.


• Four types of Philippe brackets are available:

- Standard medium twin bracket (most commonly used).

- Narrow single-wing bracket for lower incisors.- Large twin bracket.- Three- wing bracket for attachmentof

intermaxillary elastics and application of simple third-order movements.


• Clinical applications:

- Post – treatment retention.- Closure of minor spaces.- Limited intrusion.- Correction of simple tooth malalignments and

mild crowding, especially in the mandibular arch.


Customised brackets & archwires for lingual orthodontic treatment (AJODO

2003)• Developed by Weichmann et al in 2003.Weichmann et al in 2003.• In this technique, the processes of bracket

fabrication and optimized positioning of the fabricated brackets on the tooth are fused into one unit.

• Each tooth has its own customized bracket, made with state-of-the-art CAD/CAM software coupled with high-end, rapid prototyping techniques.


Diagnosis & Treatment Planning


DiagnosisDiagnosis

• Case diagnosis is conducted in a manner similar to established procedures.

• Additional diagnostic input may be required from the periodontist, restorative dentist, and orthognathic surgeon, as well as some additional psychological acumen on the part of the orthodontist.


Treatment PlanningTreatment Planning• The treatment plan is based upon the diagnosis,

the cost and time factors, and the patient's desires.

Patient Selection.

The most important factors in selecting patients for lingual treatment are their personalities and reasons for seeking treatment.


• After the patients are informed of the treatment rationale and effects of the lingual appliance (speech, soreness, bite opening), their attitude should be one of understanding and a desire to do whatever is necessary to accomplish the optimum results.

Time & Cost Factors.

1. Examination, diagnosis, consultation, and treatment planning time are increased by 30 to 45 minutes.

2. Laboratory procedures for the indirect appliance setup increase the fixed costs.www.indiandentalacademy.com

3. Orthodontist and staff time increases by 30-50%.

4. It may be necessary to finish some patients with a conventional labial appliance.

5. A fully articulated positioner appliance may be required for detailing the lingual case.

Due to these factors, a treatment fee of 30-50% more than the orthodontist's usual adult patient fee is considered realistic, reasonable, and fair.


Periodontal considerations.

• The status of the periodontium must be carefully evaluated.

• Short lingual clinical crowns can present a contraindication to optimum lingual bracket positioning.

• The lingual appliance can cause gingival hypertrophy, as the brackets are bonded close to the gingival crest.

• Patients with a history of periodontal problems or in whom oral hygiene motivation is questionable may not be the best candidates for lingual therapy. www.indiandentalacademy.com

Restorative considerations.

• In cases where there is a loss of several teeth, extreme tipping, and multiple or complex bridgework, the lingual appliance may be contraindicated.

• Porcelain-fused-to-metal crowns or other metallic restorations may need to be replaced with provisional plastic crowns to permit lingual bonding.


Lingual crown height.

7mm of lingual crown height is necessary on the maxillary incisors in order to achieve optimum bracket placement.

Attention should be given to:• Extreme brachyfacial types with short alveolar

and crown height dimensions• Partially erupted teeth in the young adolescent

patient• Crown heights that have been diminished by

excessive wear, trauma, or restorative work• Diminutive teeth, i.e., peg lateralswww.indiandentalacademy.com

Extraction vs. Non-extraction considerations.

• In lingual orthodontics, strong molar anchorage, especially in the lower arch, makes mesial movement of molar difficult.

• Hence, in Class I cases, extraction of upper first and lower second premolars is preferred.

• In Class II cases, it is better to avoid lower arch extractions.

• In open bite and Class III cases, four first premolar extractions are considered.


Temperomandibular joint considerations.

Lingual orthodontic treatment can lead to relief of joint symptoms, probably due the disarticulating effect of the anterior brackets.


Changes induced by the lingual appliance.

1. Vertical changes.• The most immediate and readily apparent

appliance-induced change is the bite opening resulting from the lower incisors occluding on the maxillary incisor bracket bite planes.

• This bite opening is beneficial in brachyfacial cases, TMD cases and rapid tooth movement due to posterior disclusion.


Bite Plane Effect Treatment time - 3 months.


2. Antero-posterior changes.

• Because of the vertical opening and the immediate rotation of the mandible (down and back), the lingual appliance also induces a Class II tendency.

• With bite opening, A-P molar correction is easier.


3. Transverse changes.

The lingual appliance has an expansive nature. This is coupled by posterior disclusion.

• There is tendency to cause mesio-buccal molar rotation during space closure. Thus, placement of transpalatal arch is important.

• Retraction is always done on stiffer wires to prevent “bowing effect”, both in the transverse and vertical planes.


First molar rotation and second molar flaring


Transverse bowing

resulting from space closure on wires of insufficient stiffness.

Vertical bowing effects resulting from space closure on light, resilient archwires.


Indications for lingual Indications for lingual orthodontic treatmentorthodontic treatment

Ideal Lingual Cases

Nonextraction:• Deep bite, Class I with mild crowding, good

facial pattern.• Deep bite, Class I with generalized spacing,

good facial pattern.• Deep bite, mild Class II, good facial pattern.• Class II division 2 with retruded mandible• Cases requiring expansion.• Consolidation (diastema) cases.


Extraction:

• Class II, maxillary first bicuspid and mandibular second bicuspid extractions.

• Maxillary first bicuspid only extractions.• Mild double protrusions with four first bicuspid

extractions, wherein anchorage is not critical.


More Difficult Lingual Cases

• Surgical cases.• Class III tendencies.• Class II, four first bicuspid extractions.• Mesiofacial patterns and/or moderate

mandibular plane angles.• Cases with multiple restorative work.


• Acute TMJ dysfunction.• Mutilated posterior occlusions.• High angle/dolichofacial patterns.• Extensive anterior prosthesis.• Short clinical crowns.• Critical anchorage cases.• Severe Class II discrepancies.• Poor oral hygiene or unresolved periodontal

involvement.• Unadaptable or demanding personality types.

Cases Contraindicated for Cases Contraindicated for Lingual TherapyLingual Therapy


Lingual Bracket Placement


• Considering the difficulty of access, irregularity and variability of lingual tooth morphology, it is difficult to locate exact bracket positions, even on plaster casts.

• Michael Diamond (J Clin Orthod, 1983)Michael Diamond (J Clin Orthod, 1983) described the critical aspects of lingual bracket placement as follows:


1.) Variation in height (y) has a direct effect on the labiolingual position of the bracket (x).

Placement of the bracket closer to the incisal edge (y') shortens the labiolingual distance (x').


2.) Variation in tooth thickness at the same distance from the incisal edge affects bracket placement by varying the distance from the labial surface.

Tooth A is thicker than tooth B at height y, and the distance x' is greater than x.


3.) Variation in height alters the effective torque in the bracket, with either a vertical or a horizontal insertion of the archwire.


4.) Brackets placed at the same height (y) on different lingual slope angulations will be located at various distances from the incisal edge (C).

A is greater than B.


5.) Altering the angle of the bracket-positioning instrument can vary the amount of torque in the bracket slot.


Lingual Bracket Placement Lingual Bracket Placement SystemsSystems

These include:1. Torque angulation reference guide (TARG).2. Fillion’s indirect bonding system.3. The customized lingual appliance setup

service (CLASS) system.4. The slot machine5. Hiro system6. The Ray set system7. The lingual bracket jig.8. The mushroom bracket positioner.www.indiandentalacademy.com

Torque angulation Torque angulation reference guide (TARG)reference guide (TARG)

• This technique of bracket placement was developed by Ormco in 1984.

• It permits bonding of brackets in the laboratory, at an accurate distance from the occlusal edge of each tooth with respect to a horizontal reference plane.

• A labial reference gauge is used to orient individual teeth.

• Using only one unique angulation model, the TARG allows pre-programming of tip and torque before the start of treatment.www.indiandentalacademy.com

Torque Angulation Reference Guide.


• Advantages:- It is an accurate and quantified two-dimensional

system.- Allows accurate placement of the brackets on

the cast without need to cut out the teeth and place in wax.

• Disadvantages:- The system does not take into account the labio-

lingual thickness of teeth.- The distance of the bracket base and the labial

surface varies according to the level of bonding.


The Slot The Slot MachineMachine

• Introduced by Dr. T.D.Creekmore in 1986, the Slot Machine was meant to be used with the Conceal bracket system.

• It also used a labial reference to position the brackets like the TARG machine. www.indiandentalacademy.com

Fillion’s Lingual Indirect Fillion’s Lingual Indirect Bonding SystemBonding System

• This system was developed by Dr. Didier Fillion of France in 1987.

• Also known as ‘Bonding with Equalized Specific Thickness’ (BEST).

• It was designed to consider the labio-lingual thickness of the individual teeth during bracket placement.

• A caliper is added as the thickness measurement system.www.indiandentalacademy.com

• Advantages:- Relates the labio-lingual thickness of tooth to

bracket position.- Allows working directly on the malocclusion

model.


The Customized Lingual The Customized Lingual Appliance Setup Service Appliance Setup Service

(CLASS) system(CLASS) system • Described by Scott Huge, this technique

involves an integrated method of lingual bracket placement and indirect bonding.

• Method: - An ideal setup is made from the original

malocclusion cast and brackets are placed on this setup.


- These are later transferred to the original cast by individual transfer trays.

- An indirect bonding tray is fabricated for bonding.

• Advantage: It takes into account the anatomical discrepancies in the lingual surfaces of the teeth.


Hiro systemHiro system• Introduced by Hiro and later improved by

Takemoto and Scuzzo.• Method:- An ideal archwire is made on the setup using a

full size rectangular archwire.- The lingual brackets are transferred onto this

wire and secured with elastic ligatures.- Single rigid transfer trays are fabricated for each

tooth. www.indiandentalacademy.com

- The archwire is then removed and custom bases for brackets are made.

• Advantages:- There is no need to transfer brackets from the

setup model to the original malocclusion model.- Accuracy is improved due to individual transfer

trays.- Bonding of one tooth is not affected by position of

other teeth.- Rebonding is easier.


The Ray Set systemThe Ray Set system• This system utilizes a 3-dimensional goniometer

for analysis of the first-, second-, and third-order values of each individual tooth.

• Both pre- and post-setup values of individual teeth are evaluated and the amount of orthodontic tooth movement for each tooth on the setup model is calculated.


The Lingual Bracket JigThe Lingual Bracket JigDr. Silvia Geron in 1999 introduced lingual

bracket jig which is a chairside direct bonding system.

• It is used with a horizontal slot bracket.• The basic idea behind the lingual bracket jig

(LBJ) is that lingual tooth anatomy and inter-tooth relationships are amenable to a lingual preadjusted edgewise approach.


The jig transfers the Andrews Straight-Wire Appliance labial bracket prescription to the lingual surface. Thus, the bracket slots line up around the arch, parallel to one another and to the occlusal plane, while the prescription provides tip, torque, rotation, and in-out.


LBJ transfers labial bracket prescriptions to lingual bracketswww.indiandentalacademy.com

The LBJ consists of:• A set of six jigs, one for

each of the six maxillary anterior teeth, which

present the most morphological

variation of the lingual surfaces.

• An accessory universal LBJ for the maxillary

posterior teeth (no torque or angulation prescribed).


• Each jig has a labial arm and a lingual arm.• The tip of the labial arm incorporates a

prescription, similar to that of a preadjusted labial bracket.

• The lingual arm, which holds the lingual bracket, slides into the labial arm.

• When the lingual bracket is mounted on the LBJ, the lingual bracket slot is parallel to the labial slot. When the labial arm is positioned correctly, the lingual bracket is automatically placed in its correct position.


A. Labial arm of LBJ positioned on labial surface of tooth, duplicating location of labial bracket relative

to LA point.

B. Lingual bracket automatically placed in correct position.


• Advantages:

- Lingual bracket positioning with the LBJ is simple and quick, and requires no special

training.- The LBJ automatically incorporates the Straight-Wire labial prescription into the bonded lingual brackets in all dimensions. - This allows the orthodontist to perform direct as

well as indirect bonding as in-office procedures.


The Mushroom Bracket The Mushroom Bracket PositionerPositioner

• Developed by Kyung et al, in 2002, the mushroom bracket positioner is a machine for accurate bracket placement on an ideal setup.

• At present, 5th generation of MBP is available which places brackets to accept a straight wire.


Transfer Optimized Transfer Optimized Positioning SystemPositioning System

• Introduced by Wiechmann et al in 2003, this system utilizes CAD/CAM technology.

• It scans the lingual surfaces of the teeth on the ideal diagnostic setup via 3D optical scanner. The data obtained from the scan is used to fabricate fully customized bracket with adapting base pads and built-in prescription.


Bonding Techniques in Lingual Orthodontics


• Introduced by Dr. Michael Diamond in 1984.Dr. Michael Diamond in 1984.• He devised a Peri/Reflector for simplified

direct bonding in the upper arch.• Peri/Reflector is a combined mirror, tongue

retractor, and saliva ejector that can simplify bonding procedures in the upper arch. It isolates the operating area, increases brightness, and enables one to see the entire area while keeping both hands free.

Direct Bonding Technique (JCO

1984)


Peri/Reflector in patient's mouth.www.indiandentalacademy.com

Bracket placement using Peri/Reflector.www.indiandentalacademy.com

Indirect Bonding Techniques• Indirect bonding is the preferred technique for

lingual bracket placement Because of the irregular morphology of the lingual tooth surfaces and the difficulty of access Research on lingual indirect bonding started with the work of the Lingual Task Force.

• They used indirect bonding with Two Component Mix systems like ENDUR, Concise and No Mix systems like SYSTEM 1, Insta-Bond. www.indiandentalacademy.com

Indirect bonding method:

A. Teeth are cleaned, isolated, and etched.

B. A thorough rinsing, using an air-water spray and high-speed evacuator, is essential.


C. Sealant application.

D. The adhesive is injected into the bracket mesh.


E. The tray is seated with firm pressure and held with light, steady pressure for 3 minutes.

F. After 10 minutes, the tray is removed, the brackets inspected, and any deficient areas filled in with a thin mix of bonding adhesive.


Newer modifications of the indirect bonding technique:

I. Bonding in CLASS system. In this, a silicone or biostar tray is used for

the final bracket placement.


II. HIRO’S method (Resin Core Indirect Bonding system).

• Described by Hong et Hong et al in 1996.al in 1996.

• This technique makes it possible to add customized torque and in-out values to the indirect setup.

Customized torque and in-out are built into resin (*) on each bracket base.


• Upper anterior bracket slots are lined up on surveyor with flat plate.

• Transfer wires are inserted into bracket slots and extended to approximate incisal edges or buccal cusp tips.


• Inlay pattern resin indexes each transfer wire to tooth

(a = elastomeric ligature; b = transfer wire; c = inlay pattern resin).

• Complete set of customized transfer trays


III. Individual Indirect Bonding Technique.

In this system, each tooth is bonded individually. Customized trays are made for each tooth.

• Advantage: The bracket position on each tooth is not affected by the position of other teeth. Also, rebonding of a single bracket becomes easier.


IV. Customized Indirect Bonding method.

• Described by Michael Michael Aguirre in1994.Aguirre in1994.

• This method makes use of an orientation card for bracket placement.

Orientation Card


V. Convertible Resin Core system (CRCS).• Developed by Hong et al in 2000.Hong et al in 2000.• They incorporated stainless steel wires into the

transfer trays.

VI. New Customized Indirect Bonding Method.

• Introduced by Kim et al in 2000.Kim et al in 2000.• They incorporated elastomeric ligatures into the

transfer trays during the indirect bonding procedure.


Rebonding Rebonding can be done in 2 ways:

1. By using the initial trays again. Individual tooth regions can be sectioned and positioned.

2. By redoing an individual bonding tray using the same protocol.


Lingual Mechanotherapy


Treatment Sequence— General

Four primary phases of edgewise lingual mechanics:

1. Leveling, aligning, rotational control, and bite opening.

2. Torque control.3. Consolidation and retraction.4. Detailing and finishing.

• These phases are generally characterized by a progressive increase in wire stiffness. www.indiandentalacademy.com

Lingual archwires.

• Typically mushroom-shaped.• Compensating bends are made.• First order bends between cuspids and

bicuspids are made at right angles, with a generous step to allow for the differences in labiolingual thickness between cuspids and premolars.

• First order bends contacting the mesiolingual of bicuspids or first molars can also act as archwire stops. These can provide an advancing or expansive force to the arch.


A. First and second order bends contacting the teeth or brackets can act as stops and result in an expansion force as arch wire length is gained through alignment.

B. First and second order bends should be made with sufficient spacing to prevent anterior advancement or to provide for retraction mechanics.


The lingual appliance has a tendency to induce an anterior maxillary open bite.

• This tendency is difficult to control, but its prevention is very important.

• Prevention includes:1. Early control of posterior extrusion with high-pull

headgear and the early establishment of buccal segment control.

2. Minimizing anterior advancement until the rectangular archwire stage.

3. Patient education on tongue positioning.


4. Prevention of vertical archwire bowing by avoiding intra- and intermaxillary elastics until stiffer rectangular archwires are used.

5. Coordination of arches to maintain the relation of maxillary incisor bracket bite plane to mandibular incisor.

6. Early use of vertical lingual elastics on suspect cases.

7. Delaying the treatment of maxillary second molars until finishing arches.


Stage I. Leveling, Aligning, Rotational Control, and Bite Opening.

• The objectives of this initial phase of therapy are to:

1. Initiate tooth movement with light forces,2. Provide for a period of patient adaptation,3. Eliminate rotations,4. Level and align individual arches to permit wire

progression,www.indiandentalacademy.com

5. Obtain initial torque control when required,6. Establish posterior anchorage units with buccal

segments,7. Initiate posterior segment control with extraoral

traction and transpalatal arch when required,8. Reduce any excessive overbite, and9. Gain space for rotations and additional bracket

bonding.


• This is achieved using lingual archwires having a wire stiffness of less than 200 mil, combined with complete seating of the archwire within the bracket slot.

• However, a common problem with lingual edgewise brackets is the difficulty in obtaining complete archwire engagement and the tendency for the archwire to be pulled out of the bracket slot.


Elastic ligature and archwire force vectors, labial versus lingual.

Conventional ligation of lingual brackets does not exert a force along the high torque angled bracket slot . www.indiandentalacademy.com

• A ligation method termed the double-over tie has been effective with both metal and elastic ligatures in directing the ligating force more directly along the bracket-slot angle.

• This ligating technique has greatly improved the ability to eliminate rotations and maintain archwire engagement throughout treatment.


Double Over Tie. The double over ligation

method applies the ligation force along the bracket slot to seat the archwire. Double over elastic ties also exert twice the force of a conventional ligation.


Double-over Ligation Tie

A. Teeth may first be ligated together with .009" steel ligature wire. Two or more segments of elastic chain are used on each tooth, with one segment placed over the bracket before the archwire is placed. The other segment of the chain serves as a handle.


B. The archwire is then inserted over the previously placed elastic chain modules.

C. The elastic chain module is then stretched out of the gingival bracket tie wings and over the archwire.


D. The elastic chain module is then inserted into the incisal tie wing.

E. The excess chain is cut.


F. The remaining elastic ligature originates and ends at the incisal tie wing and exerts a force directly along the archwire slot.


• The immediate bite opening can present some difficulties, e.g., vertical and antero-posterior changes.

• However, it is beneficial in deep bite correction and can be used to advantage in other instances.

• The immediate posterior disclusion allows rapid molar uprighting, any mesial posterior movement desired, and crossbite corrections.


Stage II. Retraction/Consolidation Mechanics

• This is achieved using either sliding mechanics, closing loop arches, or combinations.

• The lingual archwires used for retraction are .016" round stainless steel, .0175" × .0175" TMA and .016" × .016" stainless steel.


Closing loop mechanics, .017" x .025" TMA.www.indiandentalacademy.com

Sliding mechanics: 0.016" TMA with Class I elastic thread.www.indiandentalacademy.com

Stage III. Torque Control

• Torque control is initiated early in treatment using .016" × .022" or .017" × .025" and maintained throughout treatment.

• Typically, lingual archwires used in finishing and torque control are .016" × .022" stainless steel for moderate torque and .017" × .025" TMA for full torque.


Stage IV. Detailing / Finishing.

• Finishing archwires are usually .016" × .022" stainless steel, .017" × .025" TMA, or .016" and .018" TMA when additional detailing of the occlusion is required.


Retention following lingual therapy

1. Removable "invisible" retainer.


2. Cemented chrome cobalt retainer.

3. Fixed lingual retainer.


Keys to Success in Lingual Therapy


Key 1

• Patient Selection.• Oral Hygiene and Gingival Irritation - Lingual

patients must be well educated in oral hygiene and motivated from the beginning.

• Speech Adaptation and Tongue Irritation - Patients must be forewarned of temporary speech alteration.


• Variations in Tooth Size and Anatomy.• Bite Opening and Mandibular Rotation.• Headgear and Elastics - headgear is a vital

adjunct to lingual mechanotherapy to counteract mandibular autorotation.

Key 2• Bracket Placement Accuracy – use of the TARG

for accurate bracket placement.


Key 3• Indirect bonding methods for bracket adhesion.

Key 4 • Maintaining vertical and transverse control of

buccal segments.

Key 5• Double over ties on anterior teeth.

Key 6• Buccal and lingual molar attachments.


Key 7• Correction of rotations.

Key 8• Arch form and archwire sequence.

Key 9• Archwire stiffness and torque control.

Key 10• En masse retraction.


Key 11• Light, resilient wire for detailing.

Key 12• Gnathologic positioner and retention.


Improving Patient Comfort


The following tendencies with respect to discomfort are observed in patients after the application of bonded lingual orthodontic appliances when compared with those with edgewise labial appliances:

• Tongue soreness, difficulty in chewing fibrous food.

• Difficulty in pronouncing the ‘s’ and ‘t’ sounds.• Difficulty in tooth brushing.


Didier Fillion (JCO, 1997)Didier Fillion (JCO, 1997) suggested several methods of relieving these irritation factors during lingual therapy.

I. The most irritating brackets (generally bicuspids and molars) can be covered with a light-cured periodontal protective paste (Barricaid).


Barricaid pellet preparationwww.indiandentalacademy.com

II. Patients can cover their own brackets with a silicone paste (Ortho Pack) in case of severe irritation, appliance breakage, or the need to speak in public.

Ortho Pack placed over irritating brackets by patient.www.indiandentalacademy.com

III. Patients with strong tongue-thrust habits and large tongues have more trouble adapting to lingual appliances. In such cases, a soft splint made from a 1.5mm-thick silicone material may be prescribed.


Fabrication of soft protective splint. A. Brackets bonded to working cast. B. Brackets covered with low-viscosity silicone material. C. Splint thermoformed over cast. D. Finished splint in place.www.indiandentalacademy.com

Plastic tubing placed over archwire

IV. In extraction cases, the more posterior the extraction sites, the more the tongue tends to spread out over them at rest and during sleep. The resulting irritation can be alleviated by placing a plastic protective tube over the archwire at the level of the edentulous area.


1st-order bends between cuspids and bicuspids are less irritating if placed closer

to bicuspids.

V. In first-bicuspid extraction cases, the 1st-order bend will be more comfortable if it is placed as close as possible to the bicuspid without restricting its movement.


Advantages of Lingual Advantages of Lingual OrthodonticsOrthodontics

• Facial surfaces of the teeth are not damaged from bonding, debonding, adhesive removal, or decalcification from plaque retained around labial appliances.

• Facial gingival tissues are not adversely affected.

• The position of the teeth can be more precisely seen when their surfaces are not obstructed by brackets and arch wires.


• Facial contours are truly visualized since the contour and drape of the lips are not distorted by protruding labial appliances.

• Most adult and many young patients would prefer "invisible" lingual appliances if costs, treatment times, and results were comparable to those of labial appliance treatment. Given these advantages for patients, the perfection of lingual treatment seems worthwhile.


Disadvantages of Lingual Orthodontics

• More chair time is required.• Cost generally is one-third more than labial

treatment.• Mandibular auto-rotation occurs because of the

bite plane on the maxillary anterior brackets.• Vertical and transverse control of buccal

segments often is difficult when the teeth are disoccluded.


Conclusion

The lingual appliance is no panacea; but if patients are carefully selected, lingual braces can be a valuable addition to the contemporary orthodontist’s armamentarium and provide much-needed care for that segment of the population who need orthodontic services but, up to now, would not consider any type of orthodontic correction due to aesthetic concerns.

Thus, the value of “invisible braces” is lies not in the hardware, but perhapsis best expressed by the word “invisible”.www.indiandentalacademy.com

ReferencesReferences1. Creekmore T. Lingual orthodontics – Its

renaissance. Am J Orthod Dentofac Orthop 1989; 95: 514-520.

2. Alexander CM, Alexander RG, Gorman JC et al. Lingual orthodontics: A status report. J Clin Orthod. 1982; 16(4): 255-262.

3. Kurz C, Swartz ML, Andreiko C. Lingual Orthodontics: A Status Report Part 2 Research and Development. J Clin Orthod. 1982; 16(11): 735-740. www.indiandentalacademy.com

4. Alexander CM, Alexander RG, Gorman JC et al. Lingual orthodontics: A status report Part 5 – Lingual Mechanotherapy. J Clin Orthod 1983; 17(2): 99-115.

5. Valiathan A, Sivakumar A. Lingual mechanics turning orthodontics outside in: an update. J Intl Coll Dentists. 2003.

6. Paige SF. A Lingual Light-Wire Technique. J. Clin Orthod 1982 Aug534 – 544.


7. Kinya Fujita. New orthodontic treatment with lingual bracket mushroom arch wire appliance. Am J Orthod. 1979; 76(6); 657.

8. Kinya Fujita. Multilingual bracket and mushroom arch wire technique: a clinical report. Am J Orthod Dentofac Orthop. 1982; 82(2): 120-140.

9. Hong K. Update on the Fujita Lingual Bracket. J Clin Orthod 1999; 33(3): 136-142.


10. Yen PKJ. A lingual Begg light wire technique. J Clin Orthod. 1986; 20(11): 786-791.

11. JCO interviews. Dr. Vincent M. Kelly on Lingual Orthodontics. J Clin Orthod. 1982; 16(7): 461-476.

12. Takemoto K, Scuzzo G. The Straight Wire concept in Lingual Orthodontics. J Clin Orthod. 2001; 35(1): 46-52.


13. Macchi A, Tagliabue A, Levrini L, Trezzi G. Philippe Self-Ligating Lingual Brackets. J Clin Orthod. 2002; 36(1): 42-45.

14. Wiechmann D, Rummel V, Thalheim A, Simon JS, Weichmann L. Customized brackets and archwires for lingual orthodontic treatment. Am J Orthod Dentofac Orthop. 2003; 124: 593-599.

15. Diamond M. Critical aspects of lingual bracket placement. J Clin Orthod. 1983; 17(10): 688-691.


16. Smith JR, Gorman JC, Kurz C, Dunn RM. Keys to success in Lingual Therapy: Part I. J Clin Orthod. 1986; 20(4): 252-261.

17. Smith JR, Gorman JC, Kurz C, Dunn RM. Keys to success in Lingual Therapy: Part II. J Clin Orthod. 1986; 20(5): 330-340.

18. Sachdeva RCL, Weichmann D, Rummel V. Precision finishing in Lingual Orthodontics. J Clin Orthod. 1999; 33(2): 101-113.


19. Gorman JC, Hilgers JJ, Smith JR. Lingual Orthodontics: a status report: Part 4-Diagnosis and Treatment Planning. J Clin Ortho 1983; 17(1): 26-35.

20. Gorman JC. Treatment of adults with Lingual Orthodontic Appliances. Dent Clin N Amer. 1988; 32(3): 589-620.

21. Hohoff A, Fillion D, Stamm T. Speech performance in lingual orthodontic patients measured by sonography and auditive analysis. Am J Orthod Dentfac Orthop. 2003; 123: 146- 152. www.indiandentalacademy.com

22. Chaconas SJ, Caputo AA, Ademir RB. Force transmission characteristics of lingual appliances. J Clin Orthod 1990; 24: 26-43.

23. Miyawaki S, Yasuhara M, Koh Y, Discomfort caused by bonded lingual orthodontic appliances in adult patients as examined by retrospective questionnaire. Am J Orthod Dentofac Orthop. 1999; 115(1): 83-88.

24. Geron S. the Lingual Bracket Jig. J Clin Orthod. 1984; 33(8): 814-815.


25. Kyung HM. The Mushoom Braket Positioner for Lingual Orthodontics. J Clin Orthod. 2002; 36(6): 320-328.

26. Diamond M. Improved vision and isolation for direct lingual bonding of the upper arch. J Clin Orthod. 1984; 18(11): 814-815.

27. Scholz RP, Swartz M. Lingual Orthodontics: a status report: Part 3- Indirect Bonding – laboratory and clinical procedures. J Clin Orthod. 1982; 16(12): 812-820.


28. Hong RK. Customized indirect bonding method for Lingual Orthodontics. J Clin Orthod 1996; 30(11): 650-652.

29. Hong RK. A new Customized Lingual indirect bonding system. J Clin Orthod. 2000; 34(8): 456-460.

30. Kim TW. New indirect bonding method for Lingual Orthodontics. J Clin Orthod 2000; 33(6):348-350.


31. Aguirre M. Indirect bonding for lingual cases. J Clin Orthod 1984; 18(8): 565-569.


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