A precision device for lingual bracket positioning.
It offers a simple direct and in-office preparation for indirect bonding of Lingual brackets, controlling tip, torque, in-out and height of brackets.
Suitable for Ormco Generation 7, STb and Stealth (American Orthodontics) Lingual brackets.
Fits for both 0.018” and 0.022” slot
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
A ratchet for adjusting the in-out stopper.
Each jig has a labial arm (1) and a lingual arm (2). 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 for 0.018 and 0.022 slot brackets(3) 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 (4) and an occlusal stopper for controlling the vertical position of the brackets(5).
Sliding all the anterior jigs to the same B-L distance controls the in-out position of the lingual brackets. In-out stopper (41) is adjusted with a special ratchet (6).
The height of Lingual bracket placement is controlled with an adjustable occlusal stopper (5). The zero position of the occlusal stopper is programmed to enable a final overbite of 1 mm.
Extra torque is incorporated in the LBJ to allow earlier torque control with lighter wires. and to compensate the tendency to retrocline anterior teeth during space closure. When less torque is needed the wire should be downsized
A. Take an accurate impression of the arch to be bonded. Pour up in stone.
B. Draw the labial long axis of the teeth, extend the line to the palatal side and to the palate.
C. Coat the surface with a 50-50 mix of liquid foil separator and water (Cold Mold Seal).
D. Allow separator to dry at least 6 hours.
Seating the lower arch
The lower brackets are positioned on the cast using a simple tweezers. The brackets are aligned by eyeballing considering the long axis of the teeth, the incisal edges and the marginal ridges
The transfer tray is made of two layers. The inner layer, which holds the brackets, is a soft flexible layer, and the outer layer, which provides stability during bonding is a rigid layer. The transfer tray can be made of soft and hard silicone impression materials or from or combination of clear resilient silicone (Memosil 2- Kulzer) and omnivac plate (Soft Mouth guard 3 mm.).
The light body of the silicone tray surrounds the brackets and includes the base, tie wings and any exposed portion of the brackets.
Heavy body putty (or, alternatively a soft 3 mm omnivac plate) is placed directly over the soft body material. Coverage includes the lingual, occlusal and half of the labial surfaces.
Place the working in a bowl of tap water and let soak for 15 Minutes, and then remove the tray from the model.
Light cure the composite bases again for 20 seconds.
Lightly abrade the custom base surface with Micro-etcher, and wash with soap and water. Dry with compressed air.
Use a sharp knife to generally trim tray and make releasing cuts near the brackets hooks.
Store the completed tray in a zip lock bag to prevent contamination.
The LBJ copies the labial bracket slot prescription and translates it to the lingual surface
When the labial arm, 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 in-out .