Shear Bond Strength of Self-etching Adhesive Systems to Deep Dentin

Objectives: The aim of this study was to evaluate in vitro the bond strength to deep dentin of nine self-etching adhesive systems. Methods: 100 freshly extracted human teeth were mounted in acrylic molds and the facial surfaces were grounded to expose deep dentin, which was polished to 600-grit. Specimens were randomly divided in ten groups (n=10), according to the bonding agent used: XENO III (Dentsply) (XE3), XENO IV (Dentsply) (XE4), Prompt L-Pop (3M ESPE) (PLP), SE Bond (Kuraray) (SEB), S3 Bond (Kuraray) (S3B), One Coat Self Etching Bond (Coltene Whaledent) (OCS), Protect Bond (Kuraray) (PRT), iBond (Heraeus Kulzer) (IBO), AdheSE (Ivoclar Vivadent) (ADE), Scotch Bond Multipurpose (3M ESPE) (CONTROL). The adhesive systems were applied by a single operator according to the manufacturer's instructions; the teeth were restored with the composite resin Filtek™ Supreme (3M ESPE) and stored in distilled water at 37°C for 24 hours. SBS tests were performed using an Instron Machine at a cross head speed of 1mm/min. The values were calculated in MPa and statistical analysis was performed using ANOVA (p < 0.05). Results: Mean bond strength values and SDs were: XE3 11,64±4,33 (a); XE4 4,49±2,43 (c); PLP 9,53±3,54 (a,b); SEB 5,88±4,37 (b,c); S3B 9,19±3,61 (a,b); OCS 9,86±6,24 (a,b); PRT 7,53±3,49 (a,b,c); IBO 10,38±4,97 (a); ADE 8,65±7,52 (a,b); CONTROL 8,77±5,94 (a,b,c). Same letters in parentheses indicate no statistically significant difference. Conclusion: Low shear bond strength values were obtained for all adhesive systems on deep dentin. No significant differences were found between self-etching adhesives and the control group.