The effect of saliva contamination on the bond strength of universal bonding systems to the deciduous and permanent dentin

Saliva contamination is one of the factors that reduces restoration success In this study, the effects of saliva contamination on the success of the adhesive bonding to the dentin of the primary tooth and permanent tooth were evaluated with two different universal dental adhesives by in vitro tests. Microtensile bond strength test and SEM analysis were performed. 84 third human molars and 84 primary molars were collected for the microtensile bond strength test and extra samples was prepared for SEM analysis. There were 6 teeth in each subgroup for microtensile bond strength tests. Prime & Bond Universal Bond was applied to the first 7 groups and Clearfil Universal Bond Quick was applied to the other 7 groups in accordance with the manufacturer's instructions. While the first groups did not contain contamination, the second and third groups were contaminated with saliva before the adhesive application, the fourth, fifth and sixth groups after the adhesive and the seventh groups after the adhesive polymerization. The teeth were sectioned across 1mm2 dentine beams by the Isomet device and the bond strength of all samples was measured with the Micro Tensile Tester (BISCO). Statistical analysis of the obtained data was performed with the Kruskal-Wallis test and the Mann Whitney U Test (p <0.05). It was determined that the bond strength of primary teeth was significantly lower than permanent teeth in all groups. In addition, Prime & Bond Universal bond strength values (PB-B2=19,74±4,84 and PB-B3=18,76±3,98) were significantly higher than Clearfil Universal Bond Quick values (CU-B2=11,92±3,11 and CU-B3=12,19±3,67) in groups that were contaminated before adhesive application on permanent teeth, while in contaminated groups after adhesive application, Prime & Bond Universal bond strength values (PB-B4=12,93±3,85 and PB-B6=24,46±3,85) are significantly lower than Clearfil Universal Bond Quick values (CU-B4=19,48±4,09 and CU-B6=29,80±5,63).