To ensure the longevity of the results obtained after orthodontic treatment, several important considerations must be taken into account. Teeth that have been corrected during treatment have a tendency to return to their original positions (relapse). This phenomenon is related to the elasticity of the surrounding gum tissues and the forward forces exerted on the teeth by daily oral functions such as chewing. The tendency for relapse can vary from patient to patient.

To prevent this relapse after treatment, two main types of retention methods are typically applied. The first type consists of fixed retainers (lingual retainers) bonded to the inner surface of the lower front teeth after the braces are removed. These retainers are generally not felt and are easy to clean. The second method involves removable retainers (Essix aligners), which are transparent, removable trays. These aligners should be worn for most of the day (typically 24 hours) during the first 6 months following treatment, after which the wearing duration should be gradually reduced according to the program determined by the clinician.