A Comparative Study On MTBS And Sealing Ability Of Three Adhesives To Normal Vs. Caries-affected Dentine

Early generations of dentin adhesives were relatively hydrophobic, and dry dental substrates were required for bonding. However, the bond strengths were far from desirable. When manufacturers reformulated the adhesives by adding hydrophilic resin monomers, the adhesives were able to wet the dentin. With the advent of self-etching adhesives, high concentrations of acidic (ionic) resin monomers were incorporated into the adhesives to enable them to etch through the smear layer and demineralize the underlying intact dentin. Although the incorporation of hydrophilic and acidic (ionic) resin monomers has improved the immediate bonding effectiveness; however, when these adhesives is tested in clinical trial, the bonding effectiveness of some materials appears dramatically low, whereas the bonds of other materials are more stableMost bonding studies in vitro were done with normal dentin; however, normal dentin is not the substrate that is most frequently encountered in clinic. Instead, clinicians usually have to deal with caries-affected dentin. Recent results indicated that the structural changes of caries-affected dentin could produce profound changes in the permeability of dentin matrix to resin monomers. This, in turn, would influence the quality of the bond between resins and dentin.In this thesis, we evaluate the micro-tensile bond strengths and the sealing of...