title: Microleakage of class V resin composite restorations after bur, air-abrasion or Er:YAG laser preparation.
abstract: This in vitro study compared the microleakage of Class V resin composite restorations placed in cavities prepared with a high-speed dental bur, air-abrasion or Er:YAG laser. Twenty sound extracted human third molars were selected and randomly assigned to four equal Groups (n=10): Group I, cavities were cut by dental drill at high-speed; Group II, aluminum oxide air-abrasion was used for cavity preparation, and in Groups III and IV, cavities were prepared by Er:YAG laser. Following cavity preparation, Groups I and II were acid-etched, Group III was treated only by Er:YAG laser and Group IV was conditioned by Er:YAG laser followed by acid-etching. Cavities were restored (Single Bond + Z-100) and the teeth stored for seven days in distilled water. Then, the restorations were polished and the specimens thermocycled, immersed in a 0.2% Rhodamine solution, sectioned and analyzed for leakage at the occlusal (enamel) and cervical (dentin/cementum) interfaces using an optical microscope connected to a video camera. The images were digitized and software was utilized for microleakage assessment. Upon analyzing the results, statistically significant differences (p<0.01) between the occlusal and cervical regions for all groups was observed, and, as a rule, there was better marginal sealing at the enamel margins. The highest degree of infiltration was observed for cavities prepared and treated exclusively by Er:YAG (Group III). The other experimental groups showed statistical similarities in the amount of marginal leakage at the enamel margins. However, at the cervical margins, there was a significant difference (p<0.05) between Group I and the remaining groups. None of the techniques completely eliminated marginal microleakage at the dentin/ cementum margins.
authors.affiliation: Universidade de São Paulo, Faculdade de Odontologia de Ribeirão Preto, Departamento de Odontologia Restauradora, Brazil.
authors.forename: S A
authors.initials: SA
authors.lastname: Corona
authors.forename: M
authors.initials: M
authors.lastname: Borsatto
authors.forename: R G
authors.initials: RG
authors.lastname: Dibb
authors.forename: R P
authors.initials: RP
authors.lastname: Ramos
authors.forename: A
authors.initials: A
authors.lastname: Brugnera
authors.forename: J D
authors.initials: JD
authors.lastname: Pécora
mesh_terms: D000134:Acid Etching, Dental; D020906:Air Abrasion, Dental; D003188:Composite Resins / Q000737:chemistry; D003737:Dental Cavity Preparation / Q000379:methods*; D003755:Dental High-Speed Technique; D003763:Dental Leakage; D018772:Dental Marginal Adaptation; D003793:Dental Restoration, Permanent / Q000379:methods*; D004871:Erbium; D006801:Humans; D007834:Lasers; D011897:Random Allocation
chemical_list: D003188:Composite Resins; D004871:Erbium