Evaluation of a Collagen-Reactive Monomer with Advanced Bonding Durability

Abstract

This study evaluated the use of a new collagen-reactive monomer (CRM), isocyanate-terminated urethane methacrylate precursor, which has covalent affinity to dental collagen, in the formation of dentin-resin bonds and compared it with 2 other dental adhesives. Dentin specimens were bonded with either the CRM-based adhesive (CBA), One-Step (OS; Bisco, Inc.), or a negative adhesive (NA) control and subjected to 24-h storage in water, thermocycling to simulate 1-y clinical function, or a matrix metalloproteinase–mediated aging process. We tested the microtensile bond strength (µTBS), characterized the bonding interface with an atomic force microscope, conducted micro-Raman analysis, and performed leakage tests and in situ zymography. CBA and OS exhibited comparable bonding strength after 24 h ( P > 0.05); however, there was a sharp decrease in µTBS after aging for all except CBA ( P < 0.001). Raman spectra results indicated increased collagen crosslinking and chemical reaction between the adhesive and collagen in the CBA group. CBA achieved high-quality hybridization with collagen, improving mechanical properties and integrity, and decreased the enzyme-mediated degradation of the bonding interface by inhibiting collagenolytic activity. With the promising bonding durability of coapplied CBA, CRM may be the first dental adhesive to provide strong and long-lasting resin-dental collagen bonding without the additional conditioning step. The use of CBA results in high-quality hybrid layers that protect the resin-dentin interface from harmful biological and chemical activities commonly occurring in the oral environment.

Chemistry of novel and contemporary resin-based dental adhesives

“…Regarding the etch-and-rinse approach, the developing of monomers with chemical adhesion to the dentin collagen as recently published (Xu et al, 2019;Yu et al, 2020), seems to be an exciting and promising alternative to improve the long term bond stability of restorative procedures, without adding additional clinical steps to the protocol.…”

Effect of Collagen-Reactive Functional Monomer on Etch-and-Rinse Adhesives

“…Moreover, its capacity of covalently binding to proteins inhibited the proteolytic activity of dentin endogenous gelatinases. Facilitated by the excellent water-chasing property of acetone, the cross-linking effect of FA might also help to maintain the spatial structure of the dehydrated collagen matrix and prevent its collapse, thus contributing to filling the molecular gaps between the collagen fibers (Yu, Luo, et al 2020) and forming a well-infiltrated interface, as clearly evidenced by the cross-linked lateral branches of the resin tags formed in the EA-30% group (Fig. 4B).…”

“…The essential issue of the absence of resin–collagen covalent bonding can be addressed by chemically derivatizing the acrylate ester ends in a proven cross-linker molecule (Van Meerbeek et al 2011; Giannini et al 2015). Based on this rationale, functionalized monomers such as acrylated grape seed extract (Wang et al 2021) and acrylated isocyanate (Xu et al 2019; Yu, Luo, et al 2020) were developed and evidenced for their binding to collagen and improved resistance to enzymatic degradation of collagen. However, despite the encouraging results exhibited by these inhibitors and cross-linkers, the fundamental problem of the hydrolysis of the resin matrix remains unsolved.…”

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

“…SB2 was premixed with tetramethylrhodamine B isothiocyanate (Millipore Sigma, St. Louis, MI, USA) and three teeth from each group were bonded and aged as described above. Two-millimeter thick slabs that contained the bonding interface were obtained and subjected to an in situ zymography test using the EnzChek collagenase kit (E−12055; Molecular Probes, Eugene, OR, USA) as previously described [ 41 ].…”