Er:YAG Laser Cavity Preparation and Semi-Direct Composite Resin Restoration: A Microleakage Study

Abstract

This study was performed to assess the microleakage of composite resin restorations bonded in Er:YAG laser-prepared cavities using a semi-direct technique, in comparison with diamond bur-prepared cavities. Previous in vitro studies assessed the performance of total-etch and self-etch adhesive systems by investigating the microleakage of direct composite resin restorations. Class V cavities were randomly prepared in buccal and lingual surfaces of 20 human molars using a diamond bur and an Er:YAG laser (fluence 50 J/cm2). Composite resin inlays were bonded using a self-curing adhesive system and a composite resin luting cement. Microleakage was assessed using a methylene blue dye penetration method. The length of dye penetration along the occlusal margin, the length of dye penetration along the cervical margin, and the total length of the interface were recorded in millimeters. The total length of infiltration and the ratio of infiltration were then calculated. The ratio of dye infiltration was 0.20 +/- 0.22 for bur-prepared cavities and 0.27 +/- 0.30 for Er:YAG laser-prepared cavities, with no significant difference (Wilcoxon test, p = 0.77). In terms of microleakage, our results supported the use of the Er:YAG laser to remove carious tissues and prepare cavities in clinical practice.