The dark side of fixed retainers: Case series

This article focuses on on the presentation and management 9 adult patients who experienced complications because of their maxillary or mandibular fixed retainers 5-33 years after orthodontic treatment. Such complications include the development of an anterior crossbite, open bite, incisal cant, and twist- and x-effects. The detrimental effects on periodontal health were highlighted, especially in the mandibular canines. A range of fixed retainer types was identified, including flexible spiral wire bonded to 4 maxillary or 6 mandibular anterior teeth, rigid wire bonded to mandibular canines only and fiber-reinforced composite fixed retainer. Orthodontic retreatment was necessary in all patients using fixed appliances or clear aligners. Radiographic findings from cone-beam computed tomography or orthopantomogram before and after retreatment are presented when available. Despite the improvement of teeth position clinically, the cone-beam computed tomography scans taken directly after the completion of orthodontic retreatment did not show notable improvement with regards to root proximity to the cortical plates. The prevention of further complications was highlighted, including the use of dual retention, remote monitoring, frequent follow-up appointments and the importance of developing clear guidelines for monitoring patients in retention for treating clinicians and general dentists to promote early detection of adverse changes.