The Effects of Fixed Versus Removable Orthodontic Retainers on Stability and Periodontal Health: 4-Year Follow-Up of a Randomized Controlled Trial.

Introduction: Long-term or even indefinite retention is routinely prescribed after orthodontic treatment as a preventive safeguard against post-treatment changes induced by tooth movement, physiological healing, and the aging process. Though both fixed and removable versions of retainers may be equally effective in terms of results, sufficient research to support this assumption is missing at the moment.

Objectives: Long-term effects of fixed and removable retention on the periodontium, and the compliance level when used for an extended period of time.