Dentin Biomodification Potential Depends on Polyphenol Source

Abstract

Although proanthocyanidins (PACs) modify dentin, the effectiveness of different PAC sources and the correlation with their specific chemical composition are still unknown. This study describes the chemical profiling of natural PAC-rich extracts from 7 plants using ultra high pressure/performance liquid chromatography (UHPLC) to determine the overall composition of these extracts and, in parallel, comprehensively evaluate their effect on dentin properties. The total polyphenol content of the extracts was determined (as gallic acid equivalents) using FolinCiocalteau assays. Dentin biomodification was assessed by the modulus of elasticity, mass change, and resistance to enzymatic biodegradation. Extracts with a high polyphenol and PAC content from Vitis vinifera, Theobroma cacao, Camellia sinensis, and Pinus massoniana induced a significant increase in modulus of elasticity and mass. The UHPLC analysis showed the presence of multiple types of polyphenols, ranging from simple phenolic acids to oligomeric PACs and highly condensed tannins. Protective effect against enzymatic degradation was observed for all experimental groups; however, statistically significant differences were observed between plant extracts. The findings provide clear evidence that the dentin bioactivities of PACs are source dependent, resulting from a combination of concentration and specific chemical constitution of the complex PAC mixtures. A supplemental appendix to this article is published electronically only at http://jdr.sagepub.com/supplemental.

A galloylated dimeric proanthocyanidin from grape seed exhibits dentin biomodification potential

“…Each dentin beam was kept immerse in 100 μL treatment solution for 1 h in a 96 well plate, protected from light. The modulus of elasticity (in MPa) was obtained at baseline and post treatment using a universal testing machine in a three-point flexural assay [5, 16]. …”

“…Both the degree of polymerization (DP) and galloylation of the OPACs have been identified as key structural features that influence the overall dentin-targeting bioactivities [14-16]. The lack of commercially available standards, due to challenges in isolating pure OPACs, is an obstacle that stands in the way of both dental researchers and phytochemists.…”

Remineralization Potential of Mints Containing Bioactive Agents in Artificially Induced Root Caries

“…GT extracts are rich in monomeric proanthocyanidins (PACs), such as EGCg and epicatechin gallate [Aguiar et al, 2014]. PAC-rich plant extracts (including GT) can enhance the biomechanical properties and reduce the biodegradability of the dentin organic matrix by direct interaction with collagen fibrils and/or enzymatic inhibition [Castellan et al, 2010Bedran-Russo et al, 2011;Aguiar et al, 2014].…”

“…PAC-rich plant extracts (including GT) can enhance the biomechanical properties and reduce the biodegradability of the dentin organic matrix by direct interaction with collagen fibrils and/or enzymatic inhibition [Castellan et al, 2010Bedran-Russo et al, 2011;Aguiar et al, 2014]. The mechanism of action of PACs are direct interactions with type I collagen in dentin by mediating covalent-like bonds in collagen cross-linking [Vidal et al, 2016].…”

“…Among commonly found monomeric catechins, EGCg is the most potent monomeric PAC in dentin, being attributed to the 3-0-galloylation moiety [Vidal et al, 2014a]. Therefore, it is plausible to state that higher concentration of EGCg will increase the bioactivity of an extract [Aguiar et al, 2014].…”