Threats to adhesive/dentin interfacial integrity and next generation bio‐enabled multifunctional adhesives

Abstract

Nearly 100 million of the 170 million composite and amalgam restorations placed annually in the United States are replacements for failed restorations. The primary reason both composite and amalgam restorations fail is recurrent decay, for which composite restorations experience a 2.0–3.5‐fold increase compared to amalgam. Recurrent decay is a pernicious problem—the standard treatment is replacement of defective composites with larger restorations that will also fail, initiating a cycle of ever‐larger restorations that can lead to root canals, and eventually, to tooth loss. Unlike amalgam, composite lacks the inherent capability to seal discrepancies at the restorative material/tooth interface. The low‐viscosity adhesive that bonds the composite to the tooth is intended to seal the interface, but the adhesive degrades, which can breach the composite/tooth margin. Bacteria and bacterial by‐products such as acids and enzymes infiltrate the marginal gaps and the composite's inability to increase the interfacial pH facilitates cariogenic and aciduric bacterial outgrowth. Together, these characteristics encourage recurrent decay, pulpal damage, and composite failure. This review article examines key biological and physicochemical interactions involved in the failure of composite restorations and discusses innovative strategies to mitigate the negative effects of pathogens at the adhesive/dentin interface. © 2019 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 107B:2466–2475, 2019.

Harnessing biomolecules for bioinspired dental biomaterials

“…This is an attractive approach as decades of work have focused on novel restorative materials that show exciting laboratory results but are then never brought to market. 402 An additional benefit of reinforcing enamel or dentin is the potential universal compatibility with any restorative material. An alternative approach to protect collagen degradation at the resin/dentin adhesive interface and prevent premature failure of resin composite restorations is collagen crosslinking.…”

pH-dependent delivery of chlorhexidine from PGA grafted mesoporous silica nanoparticles at resin-dentin interface

“…Effective dentin bonding is by far the most debated topic and gaining more attention in restorative dentistry. The use of contemporary adhesive restorations is widespread, and their long-term clinical success is dependent on their handling characteristics [ 1 , 2 ]. The resin-dentin interface is the most critical factor and is presumably considered a fragile link between composite and dentin.…”

Evolution of Network Structure and Mechanical Properties in Autonomous-Strengthening Dental Adhesive

“…Patient characteristics include high caries-risk, gingival cavity margins, and posterior teeth [ 15 ]. Indeed, most dental resins are degraded by the caustic conditions present in the oral cavity and this activity leads to the long-term release of degradation by-products [ 16 , 17 ]. These by-products accumulate at the resin/tooth interface and increase the virulence of cariogenic bacteria, provoking a degradative positive-feedback loop [ 16 ].…”