Permanent or bonded retainers are affixed to either or both the upper and lower dental arches to prevent unwanted movement of the teeth post-orthodontic treatment. These metal wires are attached to the lingual (back) face of the tooth where they are visually undetectable and allow the patient to fully enjoy their new smile.
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 correction reversal. 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. Over time, the jawbone adapts to the repositioned teeth mitigating the risk of unwanted drifting. 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.
Permanent retainers can come in several configurations. A dental lab can fabricate the retainer with already attached pads (either composite material or metal) that are bonded to the tooth. The shape of the retainer is determined from a dental mockup of your teeth. If the retainer is being made chair-side, the dentist will shape a bare wire according to the curvature of the teeth, secure it in place with either a tray or elastics, and bond it in place. The entire process takes no more than half an hour.
Cost and Longevity
Fixed retainers generally run upwards of $500 per arch, which is not considerably more than their removable counterparts that have a shorter lifespan and other drawbacks. They can last for several years with proper care.
Placement Technique is Important
Proper placement of bonded retainers is essential for preserving tooth health and preventing failure of the appliance. Your orthodontist will take care to ensure that the wire conforms to the lingual aspect of your teeth without excess tension, as this can jeopardize bond strength and facilitate unwanted movement. Furthermore, the any areas where the composite material meets the tooth surface will be smoothed out to prevent accumulation of plaque.
Improved Hygiene and Maintenance is a Must
Bonded retainers elevate the risk for plaque entrapment and subsequent cavity formation and periodontal problems. A strict oral hygiene regimen is recommended including flossing and brushing. This process can be simplified using accessories like floss threaders and interdental brushes. A WaterPik water jet system is always a welcomed addition to helping facilitate this process. This countertop-sized-machine uses a concentrated water steam to blast out foot debris in your mouth. It is available at most drug store retailers.
Pay careful attention to your orthodontist’s instructions on properly using these tools. It goes without saying that regular dental cleanings are a necessity with permanent appliances and any suspicions of device malfunction should immediately be reported to your orthodontist.
Making the Right Choice
Deciding between a removable or fixed retainer will depend on several factors. Removable appliances require less intensive hygienic practices at the cost of remembering to wear the device. They are easier to misplace, become undersized without regular use, and are costly to replace. In some instances, concurrent treatment with a removable and fixed appliance may be recommended. The benefits to be realized include more leeway if the removable retainer is forgotten and stabilization of the posterior teeth. We encourage you to communicate your desires and concerns with your orthodontist to properly determine which form of retainer is most suitable to maintain your new smile.
Butler J, Dowling P. Orthodontic bonded retainers. J Ir Dent Assoc. 2005; 51(1): 29-32. https://www.researchgate.net/publication/7945888_Orthodontic_bonded_retainers. Acccessed February 4, 2018.