title: Limitations in bonding to dentin and experimental strategies to prevent bond degradation.
abstract: The limited durability of resin-dentin bonds severely compromises the lifetime of tooth-colored restorations. Bond degradation occurs via hydrolysis of suboptimally polymerized hydrophilic resin components and degradation of water-rich, resin-sparse collagen matrices by matrix metalloproteinases (MMPs) and cysteine cathepsins. This review examined data generated over the past three years on five experimental strategies developed by different research groups for extending the longevity of resin-dentin bonds. They include: (1) increasing the degree of conversion and esterase resistance of hydrophilic adhesives; (2) the use of broad-spectrum inhibitors of collagenolytic enzymes, including novel inhibitor functional groups grafted to methacrylate resins monomers to produce anti-MMP adhesives; (3) the use of cross-linking agents for silencing the activities of MMP and cathepsins that irreversibly alter the 3-D structures of their catalytic/allosteric domains; (4) ethanol wet-bonding with hydrophobic resins to completely replace water from the extrafibrillar and intrafibrillar collagen compartments and immobilize the collagenolytic enzymes; and (5) biomimetic remineralization of the water-filled collagen matrix using analogs of matrix proteins to progressively replace water with intrafibrillar and extrafibrillar apatites to exclude exogenous collagenolytic enzymes and fossilize endogenous collagenolytic enzymes. A combination of several of these strategies should result in overcoming the critical barriers to progress currently encountered in dentin bonding.
authors.affiliation: Department of Stomatology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Hankou District, Wuhan 430030, People's Republic of China.
authors.forename: Y
authors.initials: Y
authors.lastname: Liu
authors.forename: L
authors.initials: L
authors.lastname: Tjäderhane
authors.forename: L
authors.initials: L
authors.lastname: Breschi
authors.forename: A
authors.initials: A
authors.lastname: Mazzoni
authors.forename: N
authors.initials: N
authors.lastname: Li
authors.forename: J
authors.initials: J
authors.lastname: Mao
authors.forename: D H
authors.initials: DH
authors.lastname: Pashley
authors.forename: F R
authors.initials: FR
authors.lastname: Tay
mesh_terms: D002403:Cathepsins / Q000037:antagonists & inhibitors; D003094:Collagen / Q000737:chemistry; D003188:Composite Resins / Q000737:chemistry; D003432:Cross-Linking Reagents; D001840:Dental Bonding; D003804:Dentin; D017220:Dentin-Bonding Agents / Q000737:chemistry; D004950:Esterases / Q000737:chemistry; D006801:Humans; D006868:Hydrolysis; D057927:Hydrophobic and Hydrophilic Interactions; D061965:Matrix Metalloproteinase Inhibitors; D058105:Polymerization; D019279:Resin Cements / Q000737:chemistry; D014089:Tooth Remineralization / Q000379:methods
chemical_list: D003188:Composite Resins; D003432:Cross-Linking Reagents; D017220:Dentin-Bonding Agents; D061965:Matrix Metalloproteinase Inhibitors; D019279:Resin Cements; D003094:Collagen; D004950:Esterases; D002403:Cathepsins