Shear bond strength of adhesive systems to saliva-contaminated dentin

This study evaluated the shear bond strength of two adhesive systems: Scotchbond Multi-Purpose (SBMP) and Clearfil Liner Bond 2V (CLB2V) on different dentin surface conditions. Bovine incisors were collected and prepared according to the ISO's (TR 11405) directions. The samples were divided into nine groups (n=10): 1- SBMP control group (without contamination); 2-SBMP: saliva contamination after priming; 3- SBMP: saliva contamination after bond application; 4-SBMP: saliva contamination after acid etching; 5-SBMP: as group 4 with re-etching after saliva contamination; 6-CLB2V control group (without contamination); 7-CLB2V: saliva contamination after priming; 8-CLB2V: saliva contamination after bond application; and, 9-CLB2V: saliva contamination before priming. After the storage period in water at 37°C, the samples were tested with an Instron testing machine, at crosshead speed of 0.5mm/min. The results were submitted to ANOVA (one way) and Tukey's test at 5% significance level. For SBMP groups, the mean shear bond strengths were: 1 - 4.8 MPa, 2 - 5.0 MPa, 3 - 5.2 MPa, 4 - 6.6 MPa and 5 - 4.2 MPa. There was no statistical difference among groups tested. For CLB2V groups 6, 8, 9, the mean shear bond strengths were 8.0 MPa, 6.9 MPa and 8.8 MPa respectively and demonstrated no statistical differences. Group 7 (4.7 MPa) differed from all other groups except 8. Slight salivary contamination does not influence the shear bond strength of SBMP during any stage and slight salivary contamination influences the shear bond strength of CLB2V after priming step.

Keywords
dentin-bonding agents, saliva, contamination, shear bond strength, resin composite.