Permanent or bonded retainers are affixed to either or both the upper and lower dental arches to prevent unwanted movement of the teeth after orthodontic treatment. Several factors account for the risk of tooth mobilization after completion of treatment, including case complexity and the behavioral disposition of the patient. A significant number of orthodontic patients receive treatment in their late adolescence and early teen years, where forgetfulness to wear a removable retainer can play a major role in smile degradation.
Some patients are more susceptible to relapse due to the severity of their initial case, which may have included a number of rotations or gaps that required correction. In any case, the successful use of permanent retainers to maintain an orthodontically-enhanced smile is well documented and presents an attractive option for patients who favor convenience and cost savings but can observe an elevated degree of oral hygiene in return.
How Bonded Retainers Work
Bonded retainers work by countering the tendency of the periodontal ligaments to shift the teeth back to their original position. Overtime, the jawbone adapts to the re-positioning of the teeth further lowering the risk of unwanted drifting of the teeth.
The retainer itself consists of wire that is bonded to the lingual (back) side of the teeth. Generally speaking, upper retainers can span only the two front teeth or can extend out to the canines. Lower retainers are often secured to all non-molars.