Dentin biomodification: strategies, renewable resources and clinical applications

Abstract

Objectives The biomodification of dentin is a biomimetic approach, mediated by bioactive agents, to enhance and reinforce the dentin by locally altering the biochemistry and biomechanical properties. This review provides an overview of key dentin matrix components, targeting effects of biomodification strategies, the chemistry of renewable natural sources, and current research on their potential clinical applications. Methods The PubMed database and collected literature were used as a resource for peer-reviewed articles to highlight the topics of dentin hierarchical structure, biomodification agents, and laboratorial investigations of their clinical applications. In addition, new data is presented on laboratorial methods for the standardization of proanthocyanidin-rich preparations as a renewable source of plant-derived biomodification agents. Results Biomodification agents can be categorized as physical methods and chemical agents. Synthetic and naturally occurring chemical strategies present distinctive mechanism of interaction with the tissue. Initially thought to be driven only by inter- or intra-molecular collagen induced non-enzymatic collagen cross-linking, multiple interactions with other dentin components are fundamental for the long-term biomechanics and biostability of the tissue. Oligomeric proanthocyanidins show promising bioactivity, and their chemical complexity requires systematic evaluation of the active compounds to produce a fully standardized intervention material from renewable resource, prior to their detailed clinical evaluation. Significance Understanding the hierarchical structure of dentin and the targeting effect of the bioactive compounds will establish their use in both dentin-biomaterials interface and caries management.

Bonding efficiency and durability: current possibilities

“…68,196 GA can induce cross-links in collagen, consequently enhancing its mechanical properties, such as hardness, and maintaining its mechanical stability. GA may also prevent matrix degradation by crosslinking the binding and/or active sites of endogenous dentin MMPs, therefore blocking the access of such enzymes.…”

“…198 However, its high cytotoxicity makes its clinical use inappropriate. 196 Carbodiimide hydrochloride (EDC) has also been proposed as an effective collagen cross-linker as it has been shown to improve the durability and structural integrity of the adhesive interface, thus preserving its bond strength over time, and this through the formation of inter-and intra-molecular cross-links. 199,200,201,202 Moreover, EDC is one of the least cytotoxic and most stable cross linkers.…”

“…They increase the intrinsic properties of the collagen against collagenases degradation through inducing additional formation of inter and intra-molecular cross-links. 194,195 Exogenous cross-links also improve biomechanical and biostability properties of collagen fibrils 196 and are mediated by non-enzymatic reaction sources, such as chemical agents (i.e. glutaraldehyde, carbodiimide hydrochloride and natural resources) and physical methods.…”

“…glutaraldehyde, carbodiimide hydrochloride and natural resources) and physical methods. 196 Physical methods are mediated by photo-oxidative reaction, usually by light exposure, such as ultraviolet radiation (UVA). 197 Riboflavin is the most common cross-link of this class that can be induced by UVA.…”

Role of Dentin MMPs in Caries Progression and Bond Stability

“…In addition, several strategies to retain the integrity of the HL and improve the long-term dentin bond strength have been proposed (Liu et al 2011;Tjäderhane et al 2013b;Bedran-Russo et al 2014).…”