A fixed, or permanent retainer, conjures up the idea that it’s, well, permanent. Unfortunately, this is a misnomer. Orthodontists place fixed retainers after treatment to help the patient protect the positions of their aligned teeth. Fixed retainers are in addition to the removable night time retainers that patients should continue to wear for the rest of their lives.
Because of breakage and failure, fixed retainer can fail. This means teeth may move from their perfectly straight position to a less desirable position over time. Failure happens due to many reasons, including their physical characteristics like material with which fixed retainers are made. The materials vary but they tend to be soft and flexible metal alloys to allow for teeth to move just slightly in the periodontal ligament so the bone around the teeth remains strong. Fixed retains are also thin for cosmetic, comfort, and hygiene purposes. An entire fixed retainer may need to be replaced if the wires fray or snap between teeth due to their softness or thinness. In addition, metal alloys that are consistently subjected to stress can stretch. If a fixed retainer stretches, small movements of the teeth can occur and spaces between teeth can form. Though a retainer does not catastrophically fail after stretching, movement of teeth causes a relapse.
Beyond the materials they are made of, fixed retainers can fail when they become unglued from the the teeth to which they are attached. This tends to happen as a patient is eating or during a regular dental cleaning appointment. Fixed retainers are glued to the back of the teeth and the bond can be broken with movement on either the side of the tooth or on the side of the wire. This will feel odd to the patient and may even feel like their tongue is being cut. It must be repaired quickly or teeth can shift.
The last failure that can befall a fixed retainer is patient based. If the patient does not brush or floss properly, their general dentist may ask for the retainer to be removed so they can properly clean beneath it. Cavities can occur under the fixed retainer if the patient fails to upkeep proper oral hygiene. Regular visits to the general dentist are of the utmost importance to maintain oral health while preserving alignment.
The patient can help themselves by feeling around and looking at their retainer on a nightly basis to notice any changes. If a teeth shift is noticed, it is best to alert the orthodontist right away. The patient can also wear their removable retainer every night. These things combined with regular check ups with a general dentist will help to sustain a beautiful smile for years to come.