Flash-free and conventional adhesive ceramic brackets in patients undergoing orthodontic treatment: A systematic review and meta-analysis.

To investigate whether flash-free adhesive ceramic brackets (FFA) have a better clinical performance than conventional adhesive ceramic brackets (CVA) in patients undergoing multi-bracket orthodontic treatment. PubMed, CENTRAL, Web of Science, Scopus, Embase, CNKI and Grey-literature were searched without restrictions up to January 2022. Both randomized controlled trials (RCTs) and controlled clinical trials (CCTs) were included. Risk of bias assessment was performed using the RoB 2.0 and ROBINS-I cochrane risk of bias tools. Eight articles, for seven studies, were included in this systematic review, and four split-mouth trials (SMT) were included in the meta-analysis. A random-effects meta-analysis found a statistically significant faster bonding time with FFA (mean difference [MD] = -93.85 seconds/quadrant, P = .002, 2 SMT), and no statistically significant difference regarding bracket failure rate at 6 months (risk ratio [RR] = 1.05; P = .93, 3 SMT), adhesive removal time (MD = -18.26 seconds/quadrant, P = .50, 2 SMT), and amount of remnant adhesive (MD = -0.13/bracket, P = .72, 2 SMT) between FFA and CVA. No difference (P > .05, 3 SMT) was found in enamel demineralization and periodontal measurements. CVA showed a statistically significant higher debonding pain score (P = .004, 1 SMT). Both flash-free and conventional adhesive ceramic brackets had a similar clinical performance, except for the faster bonding with FFA. Further, well-designed clinical trials are still required.