[Orthodontic fixed retainer: fix or not fix? that is the question]

Orthodontic fixed retainer is widely used, as an orthodontic retention appliance, for nearly four decades. It answers the need for prolonged retention with minimum patient compliance. The effectiveness of fixed retainers was compared to other retention devices in several studies, and was found as effective as removable appliances. But, further high quality research is still needed. A bonded fixed retainer was suspected as an obstacle that impedes the patient's ability to keep satisfactory oral hygiene. But research failed to prove the influence of fixed retainers on periodontal health or white spot lesion occurrence as clinically significant. The definite downsides of fixed retainer are the risk of retainer breakage, and unwanted tooth movements. A typical tooth movement can appear even without a retainer breakage, including a change of torque of a mandibular incisor or skewing of the anterior mandibular arch segment. Both the dentist and the orthodontist are encouraged to be familiarized with these possible side effects, recognized them as soon as possible, and consider changing the retention protocol, when appropriate.