This book is about evaluation of marginal adaptation of a Class V composite resin restorations of five groups with different surface treatments; laser with total acid etch, laser with self-etch, laser only, total etch only and self-etch only at four different composite/tooth interface regions (gingival, mesial, distal and occlusal regions). Twenty five sound human third molar of approximately comparable sizes were chosen for this study, the cavity of standardized class V was made in the buccal and lingual side of each tooth,Tetric N-ceram was used as a restoration, then all the specimens are subjected to thermocycling and mechanical load cycling. The marginal gap was detected by using scanning electron microscope. The results of this study showed that the teeth were treated with laser and total etch showed highly significant more marginal adaption at gingival, mesial, distal, occlusal regions in comparison to other groups and the group in which the teeth were treated with laser showed highly significant less marginal adaption in comparison to other groups.