Reduction of the dentin proteolytic activity after short periods of application of proanthocyanidin

AbstractIntroductionCollagen cross-linkers have been investigated as inhibitors of the enzymatic activity of dentin, therefore improving the longevity of adhesive restorations.PurposeTo evaluate the effect of etched dentin treatment with proanthocyanidin (PA) in short periods of time on the inhibition of dentin metalloproteinases (MMP) activity in situ.Material and methodForty dentin specimens (1x1x6mm) were obtained from sound third molars and divided into 4 groups (n=10). The specimens were etched with 37% phosphoric acid for 15s and rinsed in deionized water. Then they were treated with the following solutions: water, 5% PA for 5s, 15s or 30s. The total MMP activity was analyzed by a colorimetric test (SensoLyte®). Absorbance data (412nm) were submitted to ANOVA and Tukey tests (α=0.05).ResultAll treatment periods were able to reduce the total activity of MMPs. The best results were observed for dentine treated with PA for 15s (63.1% reduction) and 30s (70.2%). Treatment for 5s was capable of inhibiting only 39.9% of the total MMP activity.ConclusionApplication of PA on the etched dentin in extremely short periods of time reduced the MMPs activity of dentin, even after 5s. However, the best results were obtained for the longer periods.