Objective: The aim of this in vitro study was to assess tensile bond strength of dentin-resinous system interfaces conditioned with Er:YAG laser irradiation.
Background data: There are different results reported in the literature which relate to laser Er:YAG effects on dentin surface as a pretreatment during adhesives procedures.
Materials and methods: Forty-two surfaces of human dentin from third upper molar were used after being extracted and kept in the refrigerator in 0.5% chloramines aqueous solution and then divided into three experimental groups and three control groups. The chosen restorative systems were Alert (Jeneric/Penton), Prodigy (Kerr Co.), and Z-100 (3M Co.), with correspondent dental adhesives Bond 1, Optibond Solo, and Single Bond, respectively. To conduct tensile tests, a special system of pairs of rods aligned in a specific apparatus was used, in accordance with ISO/TR 11405 standard (1994).
Results: By means of statistical analysis, the Kruskal Wallis test, it was noticed that group IE (laser + acid + Alert), 18.89 MPa, differed considerably from group IC (acid + Alert), 8.03 MPa (p < 0.10), but did not differ from the other groups. Group IIC (acid + Prodigy), 19.88 MPa, differed from group IIE (laser + acid + Prodigy), 12.57 MPa (p < 0.05), but did not differ from groups IIIE (laser + acid + Z-100), 14.11 MPa, and IIIC (acid + Z-100), 19.58 MPa. Group IIIE did not differ statistically from group IIIC.
Conclusion: It was concluded that previous Er:YAG laser treatment on the dentinal structure only improved the tensile bond resistance of the Alert restorative system.