This article sought to compare the influence of moisture and the effect of moisture-insensitive primer (MIP) on shear bond strength (SBS). This study divided 160 extracted teeth randomly into 2 groups (n = 80): Group 1 (enamel) and Group 2 (dentin). Groups 1 and 2 were divided into 4 subgroups (n = 20), according to the surface treatment administered. Subgroup A samples were etched and primed, and received composite resin; Subgroup B samples were etched, contaminated with artificial saliva, and primed before application of composite resin; Subgroup C samples were etched, primed, and contaminated before application of composite resin. Subgroup D samples were etched, primed, contaminated, and primer was applied a second time before application of composite resin. All the specimens were stored in distilled water and thermocycled for 500 cycles; at that point, SBS was tested. According to Tukey's test, only the mean values in Subgroups A and C revealed statistically significant differences (P < 0.05). The use of MIP on contaminated etched tooth surfaces achieved comparable bond strength to noncontaminated tooth surfaces and might have a role in restorative dentistry cases where moisture contamination is inevitable.