The effect of Er,Cr:YSGG irradiation on microtensile bond strength of composite resin restoration / 대한치과보존학회지

ABSTRACT

The purpose of this study was to evaluate the effect of Er,CrYSGG laser irradiation with hypersensitivity mode on microtensile bond strength of composite resin. Twenty extracted permanent molars were randomly assigned to six groups, according to the irradiation of Er,CrYSGG laser, adhesive system (Optibond FL or Clearfil SE bond) and application time of etchant (15 sec or 20 sec). Then composite resin was build up on each conditioned surface. The restored teeth were stored in distilled water at room temperature for 24 h and twelve specimens for each group were prepared. All specimens were subjected to microtensile bond strength and the fracture modes were evaluated. Also, the prepared dentin surface and laser irradiated dentin surface were examined under SEM. The results were as follows 1. The microtensile bond strength of laser irradiated group was lower than that of no laser irradiated group. 2. Regardless of laser irradiation, the microtensile bond strength of Optibond FL was higher than that of Clearfil SE bond. And the microtensile bond strength of 20 sec etching group was higher than that of 15 sec etching group when using Optibond FL. 3. The SEM image of laser irradiated dentin surface showed prominent peritubular dentin, opened dentinal tubules and no smear layer.