Recent developments in dentin bonding

Hybridization of the dentin with resin by monomer interdiffusion has been i dentified as the basic bonding mechanism resulting in an intimate interlock ing of the cured resin with the dentin. Today, growing efforts are made to simplify and shorten the bonding procedures, e.g. by combining the function s of primer and adhesive. Ultrastructural investigations using high-resolut ion optical technology provided exciting insight into the interactions of b onding systems and dentin. It became clear, that the maintenance or recover y of microporosities in the dentin is most important for optimal hybridizat ion. This can be achieved by the moist bonding technique, which is mandator y in acetone-based systems. The observation that certain bonding systems ar e able to bond to dentin depleted from the demineralized collagen network r aised the question of whether the collagen-resin interdiffusion mne really represents a prerequisite for successful bonding to dentin. The use of stro ngly acidic primer monomers introduced the concept of "self-etching" primer s not only to dentin but also to enamel, which eliminates the necessity of a separate conditioning step. Clinical investigations are necessary to eval uate the potential of recently developed all-in-one products which combine the functions of conditioner, primer, and adhesive. With improvements in de ntin bonding and the development of new resins that exhibit little or no sh rinkage upon polymerization, even greater applications for adhesive technol ogy will be found in dentistry.