Self-etching primer: the effect of contamination with a mixture of saliva and blood on bonding metallic brackets

Abstract

PURPOSE: To evaluate the shear bond strength (SBS) of metallic brackets bonded with Transbond Plus Self-Etching Primer (TPSEP) and Transbond Plus Color Change (TPCC) under contamination with a mixture of saliva and blood. MATERIALS AND METHODS: 42 human premolars were randomly divided into 2 groups (n=21). Group 1 (G1) were bonded under no contamination, and Group 2 (G2) was contaminated with saliva/blood before bonding. Both groups were bonded according to the manufacturer’s instructions and were cleaned with pumice before bonding. The shear bond strength (SBS) tests were performed after 24 hours in distilled water at 37°C and after thermocycling. RESULTS: Both groups showed a homogeneous distribution in the Levene’s test (p>0.05). The main shear bond strength value of G1 was 8.89 MPa with a standard deviation of 2.27; the value for G2 was 6.00 MPa with a standard deviation of 2.62 MPa. There was a significant difference between G1 and G2 (t-student test p<0.05). IRA scores indicated that the main value was IRA 0, and no significant difference (?=0.05) was found between the groups. CONCLUSION: Contamination of blood mixed with saliva significantly decreases the shear bond strength, but even so, the performance is clinically acceptable.