Evaluation of self-etching primer and erbium-doped yttrium aluminum garnet laser on bracket bond strength: An in-vitro study

Abstract

Introduction: The purpose of this study was to evaluate and compare the shear bond strength, the adhesive remnant scores and surface characteristics of the teeth prepared for bonding with erbium-doped yttrium aluminum garnet (Er:YAG) hard tissue laser, self-etching primer (SEP) and phosphoric acid etching. Materials and Methods: Seventy-eight human premolars, extracted for orthodontic purposes were randomly divided into three groups, enamel was irradiated with 37% phosphoric acid in Group-1, with SEP in Group-2 and with Er:YAG laser at 1.5-W in Group-3. After surface preparation standard edgewise stainless steel premolar brackets were bonded; one tooth in each group was not bonded and was examined under a scanning electron microscopic. The brackets were debonded 24 h later; shear bond strengths were measured, and adhesive remnant index scores were recorded. Results: Statistically significant differences were found between phosphoric acid etching, SEP, 1.5-W laser irradiation. Adhesive remnant scores were compared with the Chi-square test, and statistically significant differences were found between all groups. Conclusions: The mean shear bond strength obtained with 37% phosphoric acid etching, SEP and Er-YAG laser etching were clinically acceptable. SEP produces a more conservative etch pattern and more shear bond strength than phosphoric acid. More adhesive was left on the SEP treated enamel as compared to enamel treated with acid and laser etching.