Do fixed orthodontic appliances adversely affect the periodontium? A systematic review of systematic reviews

This overview aimed to summarize the available systematic reviews that assess the effects of treatment with fixed orthodontic appliances (FOAs) on the periodontium. Unrestricted electronic search of nine databases and additional manual searches were performed up to January 2019. Systematic reviews and meta analyses that assessed the effect of FOAs on the periodontal parameters were included. The methodological quality of the included reviews was evaluated using the A Measurement Tool to Assess Systematic Reviews2 (AMSTAR 2). The initial search yielded 2529 articles from which 19 were included in the current study. AMSTAR 2 scores ranged from critically low to high quality. The quality of evidence ranged from very low to low. The superiority of the periodontal outcomes of self-ligating brackets over conventional brackets could not be proven. The available evidence regarding the effects of FOAs on the periodontium is controversial and of very low quality. The short-term effects of FOAs were temporary worsening the periodontal parameters. Some conclusions regarding the periodontal outcomes of self-ligating brackets could be withdrawn. Future high-quality trials are required. The review was registered at the International prospective register of systematic reviews with registration number CRD42018106662.