Grape seed proanthocyanidins increase collagen biodegradation resistance in the dentin/adhesive interface when included in an adhesive

Abstract

Objectives-Contemporary methods of dentin bonding could create hybrid layers (HLs) containing voids and exposed, demineralized collagen fibers. Proanthocyanidins (PA) have been shown to crosslink and strengthen demineralized dentin collagen, but their effects on collagen degradation within the HL have not been widely studied. The purpose of this study was to compare the morphological differences of HLs created by BisGMA/HEMA model adhesives with and without the addition of grape seed extract PA under conditions of enzymatic collagen degradation.Methods-Model adhesives formulated with and without 5% PA were bonded to the acid etched dentin. Five-μm-thick sections cut from the bonded specimens were stained with Goldner's trichrome. The specimens were then exposed to 0.1% collagenase solution for zero, one, or six days. Following collagenase treatment, the specimens were analyzed with SEM/TEM.Results-Staining did not reveal a difference in the HLs created with the two adhesives. SEM showed the presence of intact collagen fibrils in all collagenase treatment conditions for specimens bonded with adhesive containing PA. These integral collagen fibrils were not observed in the specimens bonded with adhesive without PA after the same collagenase treatment. TEM confirmed that the specimens containing PA still showed normal collagen fibril organization and dimensions after treatment with collagenase solution. In contrast, disorganized collagen fibrils in the interfacial zone lacked the typical cross-banding of normal collagen after collagenase treatment for specimens without PA.Conclusions-The presence of grape seed extract PA in dental adhesives may inhibit the biodegradation of unprotected collagen fibrils within the HL.

Dual function of proanthocyanidins as both MMP inhibitor and crosslinker in dentin biomodification: A literature review

“…As mentioned in PA-collagen interactions, hydrogel formed by GAGs can function as a molecular-sieve which limits resin penetration between collagen fibrils, so such diminishing effect on GAGs content will raise hybrid layer quality. HYP assay confirmed the reinforcing mechanism of GSE and GD on collagen fibrils, however there was an inverse relationship between GSE concentration and HYP release into the incubation media, while the same relationship was not found for GD group, probably due to the restricted covalent interactions of GD with dentin 85,93,94) , it was found that transient PA pretreatment of demineralized dentin before adhesive bonding will not compromise the D.C and curing behavior of the adhesive. Current study showed that in a same pre-treatment time, 15% PA group bonded with Adper TM Single Bond 2 (SB, 3M ESPE) showed higher µTBS values compared to GD-pretreated group.…”

“…For the first time in 2010, Green et al 85) , added 5 wt% GSE PA into a model adhesive similar to single bond plus adhesive (3M ESPE, St. Paul, MN, USA) 86) , so that final PA-incorporated model adhesive was composed of solvent(ethanol)/monomer/PA mass ratio of 37/60/3. It was reported that despite the dark color of PA, there was no considerable color difference between PA-incorporated model adhesive and pure adhesive.…”

Influence of Grape Seed Extract Solution on Microleakage Between Composite Resin and Dentin

“…Proanthocyanidin consists of a free hydroxyl phenyl group that has the ability to bind a protein amino acid. The phenyl hydroxyl group forms [10,[17][18][19]. Therefore, in this study, the application of GSE solution for 30 seconds was sufficient for increasing the cross-linking of collagen dentin, according to research by Liu and Wang [9].…”

The Efficacy of Riboflavin for Collagen Cross-Linking and Optimizing the Bond Strength of an Etch and Rinse Adhesive System to Dentin

“…It appears that increasing the collagen resistance to biodegradation can further stabilize the resin-dentin interface (8)(9)(10). Collagen cross-linkers can protect collagen fibrils from degradation and enhance their mechanical and chemical properties (11)(12)(13).…”