Pulpal response, bond strength and scanning electron microscopic observations of recent dentinal adhesives in normal and sclerotic dentin

ABSTRACT

Adhesion between dention and restorative resins is of primary importance in clinical practice attaining a bond to dentin is complex mainly because is a vital tissue with a high water and organic content the current generation of dentin adhesives, shows greater promise than their predencessors, with bond strength to dentin often approaching those to enamel. The influence of surface treatment of two dentinal adhesives [scotchbond 2 and scotchbond multipurpose] having the same mode of action on the structure of the dentin was studies. The effect on the pulp was also evaluated. Shear bond strength to normal and sclerotic dentin was tested and their failure patterns were observed by SEM the conclusions obtained from this study are. 1- Scotchbond multipurpose was found to have better chance of resisting fracture than scotchbond 2. 2- The retention of the composite resin restoration and its marginal integrity are enhanced by the peneteration of resin into acidectched cross cut dentin. 3- Etching sclerosed dentin make the surface dentin les brittle and more permeable and further increase the bond strength. 4- The distance the resin penetrates depends on how far from the surface the tubules have been emptied thereby securing tags of sufficient length in the dentinal tubules, so as they remain in place and are not too easity pressed out or worn away. 5- The pulp response was favorable and leading to the production of reparative dentin. 6- The pulpal irriatation caused by acid etching of dentin for composite restorations is transitory only when the fillings have a good marginal seal and wall adaptation