The effect of phytic acid on enzymatic degradation of dentin.

We evaluated the effect of phytic acid on matrix metalloproteinase (MMP)‐ or cysteine cathepsin (CC)‐mediated dentin degradation. Demineralized dentin beams were divided into five groups (n = 12) and treated with 1%, 2%, or 3% phytic acid or with 37% phosphoric acid. Untreated demineralized beams served as controls. After incubation for 1 or 3 wk, dry mass loss was determined and aliquots of incubation media were analysed for cross‐linked telopeptide of type I collagen (ICTP) fragments for MMP‐mediated and c‐terminal telopeptide of type I collagen (CTX) for cathepsin‐k‐mediated degradation. The direct effect of phytic acid was evaluated using MMP activity assay. Data were analysed using repeated‐measures anova. ICTP releases with 1% and 2% phytic acid treatment were statistically significantly lower than those following phosphoric acid treatment at 3 wk. The CTX release for phytic acid‐treated beams at 3 wk was not significantly different from that of untreated control beams, but it was significantly lower than that of phosphoric acid‐treated beams. Their MMP activities at 3 wk were not significantly different from those of the controls but they were significantly lower than those seen for phosphoric acid‐treated beams. Compared to phosphoric acid, phytic acid treatment resulted in a reduced dentinal host‐derived endogenous enzymatic activity and collagen degradation. [ABSTRACT FROM AUTHOR]