The article describes in vitro evaluation of the micro-shear bond strength between composite resin and dentin specimens treated with self-etching, total-etching and universal dental adhesives for patients of different ages. The authors compared microstructure of resin-infiltrated zone for self-etching, total-etching and universal dental adhesive systems by means of scanning electron microscopy. These findings presented negatively effects of aging on the bond strength of dentinal surfaces and the advantages of adhesive protocol with universal adhesives for all ages.