Methods: Dentin beams (1×2×6mm) were completely demineralized in 10% phosphoric acid. After baseline measurements of the dry mass, the beams were divided into test groups (n = 9) and incubated at 37 °C in an incubation media (1mL) containing 0.02 (CM, control), 0.2, 0.5, 1, 5, 10, 20, 30, 40 mM ZnCl2. Determination of the changes in the dry mass of the beams and C-terminal telopeptide analysis of the incubation media were performed after 24 hrs. The data were analyzed using ANOVA, α=0.05.
Results: Increased zinc ion concentration resulted in less collagen cleavage at 24 hrs. Mass loss decreased significantly when zinc concentration increased (p<0.05). Similarly, less CTX release were observed by increasing zinc ion concentration (p<0.05).
Conclusions: Zinc concentrations much higher than the physiological levels may protect the MMP-induced dentin collagen degradation. However, long-term efficiancy of the enzyme inhibition should be tested in the further studies.