THE LINGUAL SELF-LIGATING BRACKET SYSTEM

 

Moshe Davidovich, D.D.S., M.M.Sc., Israel


www.lingualnews.com  Vol 2 No. 1, May 2004

To all the loyal readers of Lingual News, I would like to relate to you my initial experience using the EVOLUTION LT (registered trade mark) brackets. This is a selfligating lingual bracket produced by Adenta (Germany) which is a family owned and run orthodontic supply company. I had the pleasure of meeting the company founders during the 2003 American Association of Orthodontists annual session held in Hawaii. I had a serious discussion with them about the clinical usage of the lingual bracket system they were promoting. As such, I endeavored to try their product on a selected case. I decided to limit myself to the maxillary arch where premolar extractions were deemed to be necessary. Such a case presented itself in a 28 year old female who was highly desireous of orthodontic treatment but had a history of dental neglect due to her fear and anxiety concerning dentistry in general. She required several visits to the dental hygienist, and a dental examination prior to beginning orthodontic treatment. She presented with an Angle's Classification type I malocclusion, severe crowding, proclined maxillary and mandibular incisors, previous endodontic treatment of hermandibular right first permanent molar and left second molar. In addition, her mandibular left first molar was decayed and non-restorable. All teeth were present in the mouth, including third molars (Figure 1).

Fig 1:  Pretreatment intraoral photographs

Since her medical history was within normal limits, and her periodontal consultation did not present any contraindications, orthodontic treatment was planned. This included the extraction of her maxillary right and left first premolars and the manbibular right and left first permanent molars. A set-up was done of the maxillary anterior teeth in a manner suggested by Adenta using placement jigs to orient the brackets on the model prior to fabricating a silicone matrix for indirect bonding. The mandibular teeth were bonded directly with Inspire (Ormco) brackets from canine-to-canine, while the posterior teeth had attached to them mini diamond (Ormco) brackets.
Initial arch wires placed were a 0.016 inch nickel titanium in the maxillary dentition, and a passively bent 0.016 inch stainless steel wire in the mandibular dentition. The later wire would be used to protract the second permanent molars while retracting the premolars using nickel titanium closed coil springs. This was done without aligning the anterior teeth in order to avoid their proclination.
Placement of the initial as well as ensuing arch wires in the maxillary brackets proved to be a quick and simple procedure. The "door" on each bracket is actually an active spring clip. This clip is open and closed using what is basically a modified explorer instrument which performs is function using two fingers in a simply and quickly. In the anterior brackets, the path of wire insertion is almost totally vertical, making for a simplified bracket changing procedure. In addition, the design of the bracket "door" is such that, when closed, it acts as the bite table aspect of other common lingual brackets. In this way, the door has little chance of opening inadvertently.
Once leveling of the maxillary dentition was achieved, space was created for the permanent right central incisor by changing to a 0.016 inch stainless steel arch wire and using class 1 forces to retract the canine and lateral incisor on that side. Rotation control during canine retraction was excellent (Figure 2).

Fig 2: Intraoral photographs during alignment of upper and lower arches

At this point in treatment the patient presents with bilateral canine neutrocclusion, as well as neutrocclusion of her second molars. There is still a fraction of the extraction spaces to be closed in each quadrant. This will be completed using both class1 and class 2 forces .

I am looking forward to reporting on this case when it is completed. I am curious, as I'm sure you all are, with regard to the third order control offered by these brackets. At this point the only drawback to this system is its cost, which is nearly double that of other lingual brackets. Perhaps you get what you pay for. We will see!  

www.lingualnews.com 
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