Elastic traction with Essix-Based Anchorage

Rinchuse DaJ., Rinchuse DoJ., Dinsmore C., J. Clinc Orthod 34;1;46-48

Review: Geron S., D.M.D, M.Sc

www.lingualnews.com,  Volume 1, Number 1 - November 2002

I would like to expose the electronic Journal LINGUALNEWS readers to an interesting article concerning the use of Essix plates as part of an elastic traction scheme. Personally, I have found the use of Essix appliances against which elastic traction is to be carried out, to be very useful in (adult) orthodontic treatment. This is particularly so when combined with lingual orthodontic appliances where the esthetic component of any treatment is paramount. It has been my experience that the inclusion of an Essex appliance as part of my therapeutic armamentarium provides me with additional options during active treatment and post-treatment/retention.

This article describes a technique suggested by Dr. Sheridan for improving the retention of Essix appliances when inter-maxillary elastics are attached to it. In addition, a practical clinical application for adapting this appliance for elastic attachment is offered by Dr. Rinchuse.

A typical clinical scenario where the Essex appliance can prove useful could be when only one arch needs alignment but its antagonist is of use to correct problems of occlusion i.e. in serving as an anchorage unit for the attachment of Class II or Class III elastics. Other possibilities might include: dental midline correction with intermaxillary elastics, retention of Class II/III correction, or the correction of the relapse of overjet reduction.

To illustrate these points, I would like to present a relevant clinical case whose orthodontic treatment was supplemented by the use of an Essex appliance. In this instance, the appliance was used to anchor the attachment of Class II elastics to the otherwise untreated mandibular arch.

Patient PH is a healthy 29-year-old male which presented for orthodontic treatment with the chief complaint of "protruding teeth". His facial form was ovoid and symmetric, with a convex profile.
Intraorally he presented with an Angle's Class II div 1 malocclusion, 11 mm overjet and an open bite of 4mm. (Fig 1)

Fig 1: Pretreatment intraoral photographs

His individualized treatment plan consisted of referral for extraction of his maxillary left first permanent molar, due to its poor condition and prognosis, and the maxillary right second premolar. Hence, a lingual orthodontic appliance (Ormco), was delivered, and space closure was done with intra-arch elastics and Class II elastics to a lower Essix appliance.

During the 8 months it took for space closure, the patient wore the Essex appliance about 10 hours a day.(Fig 2)

                   Fig 2: Class II elastic traction to Essix plate      

Only one appliance was fabricated and utilized. Clinical intraoral photographs post space closure are presented here. (Fig 3)
During closure of the extraction sites the overjet was reduced from 11 mm to 2 mm, and the open bite from -4 to 0 mm.

 Fig 3: Post space closure intraoral photographs

The upper lingual fixed appliance was the "active" or main treatment arch, whereas, the lower arch was utilized as an aid for anchorage control. Due to selection of the Essix appliance as an adjunct to the lingual appliance, Class I and Class II retraction could be applied to resolve the malocclusion to our standards as well as satisfying the patient's esthetic requirements during treatment. This combination of a two esthetic technique has great potential.

Furthermore, the use of this non-obtrusive appliance avoids any irritation that a lingual appliance may cause. In addition, oral hygiene is simplified by the use of this removable appliance. It must also be mentioned that fabrication of an Essex appliance is more time efficient and less costly than the delivery of a fixed lingual appliance whose use is predicated on alignment, leveling and anchorage preparation. Not to mention bracket failure requiring added/emergency appointments.

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