Biocompatibility of dentin bonding agents

Dentin bonding agents were introduced to enhance the bonding of composite resins to dentin. Many commercial brands of bonding agents are now available for clinical use, and they are getting more and more popular. The third generation of dentin bonding agents seems to be more effective than earlier generations, although more complex to use. Dentin bonding agents have different chemical compositions, different mechanism of action, and different clinical application procedures and, conceivably, different biological effects on the pulpal tissues are expected. The reported biological effects of dentin bonding agents ranged from none to severe, depending on several factors. Opinions varied whether the inflammatory reactions associated with some bonding agents were due to the material per se, to bacterial ingrowth at the tooth restoration interface, or due to a combination of both factors.