Cavities Prepared by Different Parameters of Er:YAG Laser- Morphological Analysis

Objectives: The purpose of this study was to evaluate morphological changes in cavities performed by Er:YAG laser (2.94µm)(KaVo KEY 3)(LELO-FOUSP) and high-speed drill. Methods: In buccal and lingual surfaces of 27 human molars (Banco de Dentes-FOUSP) were performed cavities using different laser parameters (n=3): G1-15Hz/160mJ enamel/6Hz/200mJ dentin; G2-15Hz/180mJ enamel/6Hz/200mJ dentin; G3-15Hz/160mJ enamel/6Hz/250mJ dentin; G4-15Hz/180mJ enamel/6Hz/250mJ dentin; G5-15Hz/180mJ enamel/10Hz/180mJ dentin; G6-15Hz/160mJ enamel/10Hz/180mJ dentin; G7-15Hz/160mJ enamel/10Hz/160mJ dentin; G8-15Hz/180mJ enamel/10Hz/160mJ dentin and G9-high-speed drill. Samples were fixated (2.5% glutaraldheide, 12h, 4°C), dehydrated (25-100% ethanol), dried to a critical point and sputter-coated with gold for analysis under SEM. Results: All laser parameters used demonstrated no evidence of thermal damage and signs of burning, cracks and melting, Er:YAG laser ablated dental hard tissues, with exhibition of enamel rods, like scales, dentin surface without smear layer and dentinal tubules opened. Conclusions: Conclude that Er:YAG laser parameters were effective on ablation of hard tissues, promoting morphological changes on irradiated tissues, creating irregular and microretentive morphological pattern.