In office bracket positioning of different Lingual brackets with the new Lingual Bracket Jig (LBJ)

Silvia Geron D.M.D., M.Sc

www.lingualnews.com Vol 4 No 1, February 2006

The Lingual Bracket Jig (LBJ ) was first presented in ESLO congress in Rome in 1998, and published in JCO in 1999 (1). Until now, the appliance was utilized for all my Lingual cases. Recently a new improved version was manufactured. (Fig 1).
The LBJ is a precision device for lingual bracket positioning. It offers a simple direct bonding technique, and an in-office preparation for indirect bonding of Lingual brackets, controlling tip, torque, in-out and height of the brackets. The LBJ is suitable for Ormco Generation 7, STb and Stealth (American Orthodontics) Lingual brackets, and it fits for both 0.018" and 0.022" slot brackets. It is recommended for use by the orthodontist and staff mainly for in-office indirect bonding. Direct bonding is recommended only if brackets could not be bonded initially due to the malocclusion, or for rebonding.

Fig 1: The LBJ is a set of six jigs, one for each of the six maxillary anterior teeth (which present the main problem of morphological variation on the lingual surfaces, a special millimeter ruler, with up to 0.1 mm accuracy, and a ratchet for adjusting the in-out stopper.

The concept of the LBJ is that it copies the labial bracket slot prescription and  translates it to the lingual surface (Fig 2). When the labial extention, similar to a labial bracket, is positioned correctly, according to the LA point, the lingual bracket is automatically placed according to the prescribed torque, tip, height and inout.

Description of the LBJ
The LBJ is a set of six jigs, one for each of the six maxillary anterior teeth (which present the main problem of morphological variation on the lingual
surfaces). Each Jig is numbered and color coded. It included a special millimeter ruler, with up to 0.1 mm accuracy, and a ratchet for adjusting the in-out stopper. Each jig ( Fig 3) has a labial arm (Fig 3a) and a lingual arm (Fig 3b). The tip of the labial arm has a prescription similar to a labial bracket. The lingual tip holds the lingual bracket and can be manipulated to suit 0.018 and 0.022 slot brackets (Fig 4) The lingual arm, which holds the lingual bracket slides into the labial arm. Therefore, when the lingual bracket is mounted on the LBJ, the lingual archwire slot is parallel to the labial slot. Each LBJ has an in-out stopper controlling the in-out position of the bracket (Fig 3c) and an occlusal stopper for controlling the vertical position of the bracket( Fig
3d).

Fig 3: Each jig has a labial arm with rescription similar to a labial bracket(a) and a lingual arm which holds the lingual bracket(b). an in-out stopper controlling the in-out distance (c) and an occlusal stopper for controlling the vertical position of the brackets( d).

Fig 4:The lingual tip holds the lingual bracket and can be manipulated to suit for 0.018 and 0.022 slot brackets

In-out control
Sliding all the anterior jigs to the same B-L distance controls the in-out position of the lingual brackets. The in-out stopper is adjusted with a special ratchet (fig 5).
Vertical control
The height of Lingual bracket placement is controlled with an adjustable occlusal stopper (Fig 3d). The zero position of the occlusal stopper is programmed to enable a final overbite of 1 mm (Fig 6).

Fig 5: Sliding all the anterior jigs to the same B-L distance controls the in- out position of the lingual brackets. In-out stopper is adjusted with a special ratchet

Fig 6: The height of Lingual bracket placement is controlled with an  adjustable occlusal stopper (Fig 3d). The zero position of the occlusal stopper is programmed to enable a final overbite of 1 mm

Prescription
Extra torque is incorporated in the LBJ to allow earlier torque control with lighter wires, and to compensate the tendency of the anterior teeth to retrocline during space close (Fig 7) When less to q e is needed the i e. closure (Fig 7). When less torque is needed the wire should be downsized. When a bracket is positioned with the LBJ the initial prescription of the bracket is replaced by the prescription of the LBJ.

Fig 7: Prescription of the LBJ and brackets mounted with the LBJ

Case report
The following case report is demonstrative of demonstrating the use of the LBJ for combined direct and indirect bonding. STb and Stealth brackets can be bonded exactly the same.
A 35 year-old female presented for treatment with the main complaint of malalignment and crowding of the upper and lower teeth. Clinical examination revealed a symmetric face with increased lower facial height, convex profile with bimaxillary protrusion, gummy smile and incompetent lips. (Fig.8).

Fig 8: pretreatment facial photos

The patient had an Angle's Class II division 1 malocclusion with 8 mm overjet and 20% overbite. Both arches were ovoid, symmetric with severe crowding. Upper left central central incisor had gingival recession and was extruded. Gingival margins of the upper incisors were uneven (Fig.9).

Fig 9: Pretreatment intraoral photos

Treatment objectives
The treatment objectives were to eliminate crowding and rotations, reduce incisor proclination, level and align the dental arches. The treatment of the gummy smile was not included in the treatment objectives since the patient excluded orthosurgical treatment.

Treatment plan
It was decided to treat this patient with 4 second bicuspid extractions, and use Ormco G7 Lingual brackets.

In-Office indirect bonding

1. Cast preparation

A. An accurate alginate impression of the arches was taken and poured up in stone.
B. Labial long axis of the teeth was drawn and the line was extended to the palatal surface and to the palate.    
C. The surface was coated with a 50-50 mix of liquid foil separator and water (Cold Mold Seal).
D. The Liquid separator was allowed to dry at least 6 hours.

2. Bracket preparation

A. Ormco Generation 7 brackets 0.018" slot were used for the canine to canine upper teeth. Each bracket was mounted on their LBJ (Fig 10), except for the upper left central incisor that could not be bonded correctly
because of the crowding.(Fig 9).

Fig 10: Each bracket was mounted on their LBJ

B. The vertical position of the brackets was determined by measuring the distance (x) between the vertical stopper and the incisal edge of the labial extention (Fig 11).

Fig 11: Height measurement

C. The in-out distance was determined by measuring the width of the widest tooth (right central incisor in this case) and fixing the in-out stopper at this distance (Fig 12).
D. The Jigs of all the upper anterior teeth was moved to the same in-out distance using the millimeter ruler (Fig 12).

3. Seating upper anterior brackets

A. Using a small flat instrument such as an adhesive spatula, a small amount of a light cured orthodontic adhesive (Transbond Unitek 3M)) was placed on the base of the bracket. The paste was pushed into the mesh . A small additional amount of adhesive was placed onto the bracket base to make sure the base was completely covered. (Fig 13).

Fig 12: The in-out distance of the widest tooth is measured with the
ruler and applied to the other jigs

Fig 13: A small amount of a light cured orthodontic adhesive is placed on the base of the bracket. The paste was pushed into the mesh

B. The bracket was placed by sliding the labial arm along the labial surface of the tooth while long axes of the tooth and the labial arm of the LBJ coincide, until the labial arm is fully seated, and the occlusal stopper is in contact with the incisal edge of the tooth.(Fig 14).
C. Excess material around the bracket base was cleaned off with an explorer, and the bonding was light cured for ten seconds.
D. The bracket was held with an explorer while sliding the jig out of the bracket gently (Fig 15). All the upper anterior brackets were placed in this manner.

Fig 14: The bracket is placed by sliding the labial arm along the labial surface of the tooth while long axes of the tooth and the labial arm of the LBJ coincide, until the labial arm is fully seated, and the occlusal stopper is in contact with the incisal edge of the tooth.

Fig 15: After light curing the jig is slide out of the bracket gently, using an explorer to hold the bracket and avoid debonding

4. Seating posterior brackets

Premolar and molar brackets were Ormco G7 0.022" slot. The premolar brackets were aligned according to marginal ridges Fig 16). Molar brackets were positioned in slight tip back (Fig 17), according to the labial groove(2) ruler and applied to the other jigs.

Fig 16: Premolar brackets are aligned according to marginal ridges

Fig 17: Molar brackets were positioned in slight tip back, according to the
labial groove

5. Seating the lower arch

Lower anterior, canine to canine brackets were 0.018 " slot, premolar and molar brackets were 0.022" slot. The lower brackets were positioned on the cast using a simple tweezers. Since it was shown that the
morphological and in-out differences of the lower canines and incisors are not significant as in the upper arch (3,4) the brackets could be bonded without any special jig for torque and in-out control, expressing the brackets prescription. The brackets were aligned by eyeballing
considering the long axis of the teeth, the incisal edges and the marginal ridges. The incisal border of the bracket should be about 4 mm distance from the incisal edge of the tooth. A smaller distance will result in
visibility of the bracket. A larger distance will position the bracket too close to the gingival margins and reduce the interbracket distance unnecessarly (Fig 18).

Fig 18: The incisal border of the bracket should be about 4 mm distance from the incisal edge of the tooth. A smaller distance will resulr in visibility of the bracket. A larger distance will position the bracket too close to the gingival margins and reduce the interbracket distance unnecessarly

6. Transfer tray preparation

The transfer tray (Fig 19) is made of two layers. The inner layer, which holds the brackets, is a soft flexible layer made of flexible clear silicone impression material (Memosil 2, Kulzer), and the outer layer, which provides stability during bonding is more rigid made of thermoformed plate (Soft Mouth guard 3 mm thickness).
Step 1
The light body of the silicone tray surrounds the brackets and includes the base, tie wings and any exposed portion of the brackets.
Step 2
Themoformed soft 3 mm Omnivac plate is placed directly over the soft body material. Coverage includes the lingual, occlusal and half of the labial surfaces.
Step 3
The work is placed in a bowl of tap water and let soak for 15 Minutes, and then the tray is removed from the model.
Step 4
Composite bases are light cured again for 20 seconds.
Step 5
Light abrasion of the custom base surface with Microetcher, then the bases are washed with soap and water, and dried with compressed air.
Step 6
A sharp knife is used to generally trim tray and make releasing cuts near the bracket hooks.

7. Bonding procedure

Both arches were bonded at the same appointment. The teeth were cleaned, etched, rinsed, dried and isolated. Transbond XT Paste (Unitek) with Ortho-Solo primer (Ormco) was used for bonding. The primer was applied on the tooth and on the composite pad, the paste was added to the pad and the tray was seated on the teeth and light cured. The lower arch included a porcelain crown. The lingual surface of the crown was sandblasted with 30 microns aluminium oxide for 3 seconds, then etched with porcelain etching material, washed, dried and coated twice with porcelain primer. The Ortho-Solo primer and transbond past were now used for bonding as with natural teeth. The trays were removed by peeling off the outer thermoformed layer first, and then the inner clear silicone material was gently removed from the brackets. The outer thermoplastic trays were delivered to the patient for night wear, for improving the patients' comfort on the first days after bonding. A small clit was bonded directly on the lingual surface of the upper left central incisor, which could not be bonded properly due to the overlap with the lateral incisor. Niti 0.014 " archwire was used as the first archwire, with plastic sleeved over the wire in some areas, to avoid tonque irritation. (Fig 20).

Fig 19: The transfer tray is made of an inner layer made of clear silicome impression material and an outer vacuum form layer

Fig 20: Upper and lower arches one month after bonding

Treatment progress
After 1 month with 0.014 " Niti wire, the patient was referred for extraction of the second premolars. The upper left central incisor was rotated using a labial clear button and a chain tied from the button to the archwire. After rotation the left central incisor bracket was bonded directly with the LBJ, the same way as it was bonded on the cast, and using the same in-out and height measurements used for the indirect bonding (Fig 21). The archwire was changed to Copper Nitanol 0.017x0.017" (Fig 22), and then replaced with 0.016"x0.022" SS wire, including vertical and horizontal compensation curves.

                                          Fig 21: Direct bonding with LBJ

Fig 22: Alignment and leveling was completed after direct bonding of the left central incisor

Intermediate treatment results
Fig 23 presents the final stage of space closure, still with the SS archwires, right before starting the finishing stage. The arches are levelled and aligned, crowing in the both arches was relieved and proper functional occlusion was created with overjet and overbite within normal limits, and Class I canine relations on both sides. The dental inter and intra-arch relations at this stage predicts a simple finishing stage.
Final facial pictures show significant improvement in smile aesthetics , in bimaxillary protrusion and in mentalis strain during lip closure. (Fig 24).

Conclusions
The use of the LBJ for in-office direct and indirect bonding enabled simple, well controlled treatment of the severe malocclusion case demonstrated in this article. The well aligned dentition at the end of space closure, still with a rectangular archwire predicts a short and simple finishing procedure

REFERENCES
1. Geron S. The Lingual Bracket Jig .J. Of Clinc Ortho. August 1999,33:8, 457-470
2. Geron S., Vardimon A. Six Anchorage keys in Lingual Orthodontic sliding mechanics, World J Orthod 2003;4:258-265 
3. Creekmore TD. Lingual orthodontics - Its renaissances Am J Orthod Dentofac Orthop 96: (120-137) 1989
4. Takemoto K. The straight wire concept in Lingual Orthodontics J. Clinc. Orthod 34 No 1 Jan 2001

Fig 23: Intraoral pictures at the final stage of space closure

Fig 24: Facial photos at the final stage of space closure

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Adult and Lingual Orthodontics
EDITORS:
Dr. Silvia Geron D.M.D., M.Sc
Dr. Rafi Romano D.M.D., M.Sc
Dr. Pablo Echarri D.M.D., M.Sc