Dentin/Pulp Biocompatibility of an Adhesive System for Silorane Restorative

Purpose: To evaluate histological effects of an adhesive system for use with Silorane restorative (Exp Primer/Exp Bond) on pulp and dentin tissues of miniature swine.  Material and Methods: Three female miniature swine were used, one each for 7-, 28- and 70-day.  Experimental procedures followed ISO 7405 guidelines.  Under general anesthesia, deep Class V cavities, with or without pulp exposure, were prepared and restore using Exp Primer/ Exp Bond or Adper Scotchbond Multipurpose (control).  For the pulp exposure group, 10 and 5 teeth were used for the Exp and Scotchbond groups, respectively, for each time point.  For the deep dentin group, the sample size was 8 and 5 for the Exp and Scotchbond groups, respectively.  The treated teeth with surrounding tissues were sampled as scheduled, fixed in 10% formalin, decalcified in 10% formic acid, and prepared for slides.  Histological evaluation was conducted blind by two independent oral pathologists, and the observations were rated as normal, minor, moderate and severe.  The data were analyzed using the Fisher Exact Test.  Results: The animals grew and behaved normally throughout the experiment with no evidence of pain or discomfort.  Visual examination of the treated teeth and surrounding tissues found no abnormalities.  The overall histological findings were comparable between the Exp and Scotchbond groups in both the pulp exposure and deep dentin samples.  The observed changes were mild to moderate in most cases.  The incidence of pulp fibrosis in the 70-day Scotchbond samples was significantly higher (p=0.026) than that in the Exp group, while the 7-day Exp samples showed a statistically higher incidence of pulp hemorrhage (p=0.026).  No significant differences in other parameters were detected between the two groups.  Conclusion: The overall swine dentin and pulp responses to the adhesive system for use with Silorane restorative and Adper Scotchbond are comparable.  (Sponsored by 3M ESPE)