Effect of dentin coating on microleakage and bond strength of adhesive resin cements

Hisanori Kurashige, DDS, PhD,(a) Shiro Suzuki, DDS, PhD,(b) Hiroyuki Minami, DDS, PhD,(a) and Takuo Tanaka, DDS, PhD(a)

Department of Fixed Prosthodontics, Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima, Japan, and Department of Prosthodontics and Biomaterials, University of Alabama at Birmingham, School of Dentistry, Birmingham, AL, USA

Purpose: This study determined the effect of the application of dentin coating materials on microleakage and shear bond strengths of adhesive resin cements.
Materials and Methods: One hundred and five bovine dentin specimens for dye penetration testing and shear bond testing were ground flat with #600 grit silicon-carbide paper. The specimens were divided into fifteen groups of seven specimens each, and they were subdivided into two dentin-coated (Touch&Bond and Brush&Bond) and non-coated (control) conditions of five groups each. One out of the five groups was subjected to a microleakage test, which was performed by immersing the specimens in 5% methylene-blue for 24 hours. The remaining four groups were used for shear bond test. Shear bond specimens were fabricated by bonding Ni-Cr alloy disks with adhesive resin cements (Panavia F or C&B Metabond) both with and without post-treatment of proprietary dentin conditioners to the coated surfaces. The mean values of microleakage and shear bond strength for each group were statistically analyzed by two-way analysis of variance (ANOVA) and Bonferroni/Dunn test at a 95% confidence level.
Results: The dentin coated specimens showed significantly less dye penetration than the non-coated specimens. For both adhesive resin bonded groups, shear bond strengths of Brush&Bond coated specimens without post-treatment (7.8 MPa for C&B Metabond specimens, 1.5 MPa for Panavia F specimens) significantly increased (16.0 MPa and 21.7 MPa, respectively) through the use of dentin conditioners onto the coated surface.
Conclusion: It was suggested that appropriate post-treatments to the coated surfaces were necessary when adhesive resin cements were used for luting prostheses. (Int Chin J Dent 2006; 6: 71-78.)

Key Words: adhesive resin, dentin coating, dentin conditioner, microleakage, bond strength.