Comparison of shear bond strength of orthodontic brackets bonded to human teeth with and without fluorotic enamel: Asystematic review and meta-analysis of experimental in vitro studies.

Abstract

The aim of this systematic review was to compare the shear bond strength (SBS) of orthodontic brackets bonded to human teeth with and without enamel fluorosis (EF) using conventional bonding interventions/techniques. An unrestricted search of indexed databases was performed with the following eligibility criteria: (a) human fluorotic teeth (experimental-group); (b) human teeth without fluorosis (control-group); (c) studies using phosphoric acid (PA) etching without air abrasion (AA), PA etching combined with AA, and application of self-etching primer (SEP) alone as bonding interventions/techniques and (d) measuring SBS in megapascals (MPa). Data screening, selection and extraction were performed by two reviewers. The risk of bias (rob) was assessed using the JBI Critical appraisal tool for Quasi-Experimental Studies. Meta-analyses were performed using a random effects model. The quality of available evidence was assessed using the Grading of Recommendations Assessment, Development and Evaluation approach. Ten in vitro studies were included. Subgroup analyses were performed for each intervention type. The SBS was significantly lower in fluorotic teeth when PA was used without AA (mean difference=3.26 MPa, confidence interval: [1.00, 5.52]); and there were no significant differences for the PA combined with AA and SEP interventions. All studies had a low rob. The overall level of evidence was at best low. The SBS is lower in teeth with EF when traditional PA is used. No significant differences were found in SBS between teeth with and without EF when PA is used with AA or when SEP is used alone.