The purpose of the current research was to determine whether variation in the application of cavity antiseptics on the enamel surface of third molars prior conventional adhesion impacts or not on the tensile strength of direct restoration of resin. Four groups of 10 third molars were prepared, which were organized as follows: in group A, 2.5% sodium hypochlorite was placed on enamel surface; in group B, 2% chlorhexidine was placed on enamel surface; on group C, chemically pure calcium hydroxide was used; on the control group no antiseptic was used. Results showed the following figures: group A an average of 8.63 Mpa, much higher than the pattern (5.96Mpa); group B an average value for strength of 5.43 Mpa, which is lightly lower than the pattern; group C 3.19 Mpa, much lower than the pattern. It was concluded that the use of disinfectants, mostly sodium hypochlorite 2.5% increases the enamel-resin adhesion strength