Evaluation of Aloe vera as matrix metalloproteinase inhibitor in human dentin with and without dentin-bonding agent: An in vitro study

BACKGROUND: Proper hybrid layer formation lays the foundation of resin–dentin bonding. The resin infiltration in demineralized dentin collagen couples with the adhesive/resin composites in the mineralized dentin surface. However, the activation of enzymatic activity in the collagen matrix can degrade the hybrid layer. Over the time, it leads to reduced bond strength. Mainly, the enzymes involved are matrix metalloproteinases (MMPs) which are involved in degrading most of the extracellular matrix components. Aloe vera is an herb with an anti-inflammatory effect, but its role in human dentin as an enzyme inhibitor has not been verified yet. AIMS: The purpose of the study was designed for evaluating the inhibitory action of Aloe vera on MMP in human dentin with and without dentin bonding agents. MATERIALS AND METHODS: A total of 15 freshly extracted healthy human teeth were collected and stored at 4°C until use. The roots were separated. The enamel and remnant pulp tissue were removed, and collected teeth were pulverized with liquid nitrogen in the minimum volume of 50-mM phosphate buffer to obtain dentin powder extract. The dentin powder extract is the source of MMPs, and therefore, the extract was treated with A. vera solution and incubated to assess the enzyme inhibition by the plate assay method and zymographic analysis. RESULTS: A. vera treated sample with and without dentin bonding agent showed inhibition of dentin MMP's activity by plate assay method and confirmed by zymogram analysis. CONCLUSIONS: A. vera has the potential for inhibiting the MMPs enzyme activity of human dentin collagen with and without dentin bonding agents.