Enhancing resin-dentin bond durability using a novel mussel-inspired monomer

Abstract

Numerous approaches have been developed to improve the resin-dentin bond performance, among which the bio-application of mussel-derived compounds have drawn great attention recently. To assess the performance of N -(3,4-dihydroxyphenethyl)methacrylamide (DMA), a mussel-derived compound, as a functional monomer in dental adhesive, its potential property to cross-link with dentin collagen and polymerize with adhesive will first be evaluated by transmission electron microscopy (TEM), attenuated total reflectance technique of Fourier transform infrared (ATR-FTIR), and atomic force microscopy (AFM) via Peakforce QNM mode. After validating the influence of DMA on collagen and adhesive separately, the overall performance of DMA/ethanol solution as a primer in dentin bonding was examined using micro-tensile bond strength (μTBS) testing, fracture pattern observation, and nanoleakage evaluation both immediately and after 10,000 times thermocycling aging. The inhibitory effect of DMA on endogenous metalloproteinases (MMPs) was evaluated by in situ zymography using confocal laser scanning microscopy (CLSM) and the cytotoxicity of DMA was evaluated using cell counting kit-8. Results demonstrated that DMA successfully cross-linked with dentin collagen via non-covalent bonds and had no influence on the polymerization and mechanical properties of the adhesive. Furthermore, even after 10,000 times thermocycling aging, the μTBS and nanoleakage expression of the DMA-treated groups showed no significant change compared with their immediate values. In situ zymography revealed reduced endogenous proteolytic activities after the application of DMA, and no cytotoxicity effect was observed for DMA concentration up to 25 ​μmol/L. Thus, DMA could be used as a novel, biocompatible functional monomer in dentin bonding.

Mussel-inspired polymer with catechol and cationic Lys functionalities for dentin wet bonding

“…To address the disadvantages of the presence of water on dentin adhesion, researchers have proposed a few mussel-inspired catechol-containing polymers for use in dentin bonding that showed promising results [ [30] , [31] , [32] , 34 ]. However, these simplified polymers failed to capture the complex synergy between amino acids and catechol in natural Mfps.…”

“…The effects of CLM treatment on the degree of conversion (DC) of SB2 were evaluated using attenuated total reflectance Fourier-transform infrared spectroscopy (ATR–FTIR; Shimadzu, FTIR-8400S, Kyoto, Japan) as previously described [ 31 , 32 ]. Briefly, the top plate of the ATR–FTIR spectrometer was wiped with ethanol.…”

“…These catecholic proteins play a vital role in mussel bonding as the catechol moiety can form various chemical bonds with the substrate, including hydrogen bonds, Michael additions, cation–π interactions, and π–π coupling [ [23] , [24] , [25] , [26] , [27] , [28] ]. Accordingly, recombined mussel adhesive protein and catechol-functionalized polymers have been used as primers or etchant additives in dentin wet bonding [ [29] , [30] , [31] , [32] , [33] , [34] ]. According to previous studies, these highly active monomers can improve the types of chemical bonding forces and reduce collagen degradation at the bonding interface, thereby improving the durability of dentin bonding [ [29] , [30] , [31] , [32] , [33] , [34] ].…”

“…Accordingly, recombined mussel adhesive protein and catechol-functionalized polymers have been used as primers or etchant additives in dentin wet bonding [ [29] , [30] , [31] , [32] , [33] , [34] ]. According to previous studies, these highly active monomers can improve the types of chemical bonding forces and reduce collagen degradation at the bonding interface, thereby improving the durability of dentin bonding [ [29] , [30] , [31] , [32] , [33] , [34] ]. However, these previous studies did not involve in-depth research on the dynamic bonding process involved in water contamination.…”

Cytotoxicity and Bonding Property of Bioinspired Nacre-like Ceramic-Polymer Composites

“…Cytotoxicity is the primary consideration for the clinical applications of new biomaterials ( Li et al, 2021 ). Several previous studies have demonstrated that zirconia is not cytotoxic ( Christel et al, 1989 ; Piconi et al, 1998 ; Lohmann et al, 2002 ; Manicone et al, 2007 ; Shin et al, 2016 ).…”