Microtensile bond strength of three adhesive systems to different dentin tissues

Purpose: The aim of this in vitro study was to determine the micro-tensile bond strengths (mTBS) of three adhesive systems (Prime&Bond NT, Clearfil SE Bond, G Bond) to four different dentin structures; bovine dentin and unerupted, sound, caries affected human dentins. Materials and Methods: Flat bovine molar, unerupted, sound and caries affected human molar dentin structures were obtained at the occlusal surfaces of the extracted teeth. Final surface grindings were performed using 600-grit Silicon carbide paper. Three adhesive systems (Prime&Bond NT, Clearfil SE Bond, G Bond) were used to bond composite resin (P60, 3M ESPE) to the prepared dentin surfaces. After 24 h distilled-water storage, the bonded specimens were cross-sectioned (0.8 ± 0.2 mm 2 ) and subjected to a (μTBS) test. One-way analysis of variance multiple comparison test were used to statistically analyze the mean bond strength data α =0.05. Results: There was statistically significant difference in mTBS among the dentin types (P < 0.0005). Mean bond strength to sound human and bovine dentin was significantly higher than to caries-affected dentin and dentin of unerupted human teeth (P < 0.05). Statistically similar bond strength was obtained with Prime&Bond NT and Clearfil SE Bond while G-Bond showed the lowest bond strengths. Conclusion: The type of dentin structure has an important effect on the mTBS values of adhesive systems.