RESUMEN
Prevention of contamination during the procedural steps is a requisite for achieving a satisfactory composite restoration. The aim of this experimental study was to compare the shear bond strength of composite to enamel in two different decontamination procedures of uncured bonding and uncontaminated conditions. Thirty-six extracted sound human premolars and incisors were selected. Enamel of buccal surface was ground flat. The teeth were divided into 3 groups of 12 each. In the control group [1], 3M Single Bond adhesive was used according to the manufacturer's instructions, without any contamination. In groups 2 and 3 uncured adhesive was saliva contaminated and then: [2] rinsed, dried, etched [5 seconds], rinsed, dried, adhesive was reapplied and [3] cured, dried, etched [5 seconds], rinsed, dried and adhesive was reapplied. Then composite cylinders were bonded to enamel surfaces. Finally, samples were sheared using Instron testing machine and shear bond strength data were subjected to one-way ANOVA. The mean bond strength was 16.5317 MPa in the control group, 16.2308 MPa in rinsed contaminated bonding group and 15.8025 MPa in cured contaminated bonding group. No statistically significant difference was found in the mean shear bond strength of groups 1,2 and 3 [p=0.954]. Both decontamination protocols [groups 2 and 3] resulted in acceptable bond strength and both were comparable with uncontaminated condition