title: How to increase the durability of resin-dentin bonds.
abstract: Resin-dentin bonds are not as durable as was previously thought. Microtensile bond strengths often fall 30% to 40% in 6 to 12 months. The cause of this poor durability is a combination of the activation of matrix metalloproteinases (MMPs) by weak acids such as lactic acid released by caries-producing bacteria, and acid-etchants used in adhesive bonding systems. These acids uncover and activate matrix-bound MMPs. The other contributing factor is incomplete resin infiltration. If all exposed collagen fibrils were enveloped by resin, the MMPs would not have free access to water, an obligatory requirement of these enzymes. Recently, several inhibitors of MMPs have been added to adhesive primers. Examples include chlorhexidine (CHX), benzalkonium chloride (BAC), and MDPB, an antibacterial monomer used in a two-step self-etching primer adhesive. The advantage of MDPB over CHX and BAC is that it polymerizes with adhesive resins and cannot leach from the hybrid layer. This is an example of what can be termed a "therapeutic adhesive system" that provides anti-MMP activity along with antibacterial qualities.
authors.affiliation: Georgia Health Sciences University, School of Dental Medicine, Augusta, Georgia, USA.
authors.forename: David H
authors.initials: DH
authors.lastname: Pashley
authors.forename: Franklin R
authors.initials: FR
authors.lastname: Tay
authors.forename: Satoshi
authors.initials: S
authors.lastname: Imazato
mesh_terms: D000134:Acid Etching, Dental / Q000009:adverse effects; D003188:Composite Resins / Q000737:chemistry*; D001840:Dental Bonding / Q000379:methods*; D003806:Dentin Permeability; D017220:Dentin-Bonding Agents / Q000737:chemistry*; D024022:Fibrillar Collagens / Q000737:chemistry*; D006801:Humans; D008422:Materials Testing; D061965:Matrix Metalloproteinase Inhibitors; D020782:Matrix Metalloproteinases / Q000378:metabolism; D013499:Surface Properties; D013718:Tensile Strength
chemical_list: D003188:Composite Resins; D017220:Dentin-Bonding Agents; D024022:Fibrillar Collagens; D061965:Matrix Metalloproteinase Inhibitors; D020782:Matrix Metalloproteinases