Effect of blood contamination on shear bond strength of brackets bonded with a self-etching primer combined with a resin-modified glass ionomer.

This study assessed the effect of blood contamination on the shear bond strength and bond failure site of a resin-modified glass ionomer (Fuji Ortho LC, GC Europe, Leuven, Belgium) used with 3 enamel conditioners (10% polyacrylic acid, 37% phosphoric acid, and self-etching primer). One hundred twenty bovine permanent mandibular incisors were randomly divided into 8 groups; each group consisted of 15 specimens. Two enamel surface conditions were studied: dry and contaminated with blood. One hundred twenty stainless steel brackets were bonded with the resin-modified glass ionomer. After bonding, all samples were stored in distilled water for 24 hours and then tested in shear mode on a testing machine. The groups conditioned with self-etching primer and 37% phosphoric acid had the highest bond strengths for both dry and blood-contaminated enamel. The groups conditioned with 10% polyacrylic acid showed significantly lower shear bond strength value, and the unconditioned groups had the lowest bond strengths. For each enamel conditioner, no significant difference was reported between dry and blood-contaminated groups. Significant differences in debond locations were found among the groups bonded with the different conditioners. Blood contamination of enamel during the bonding procedure of Fuji Ortho LC did not affect its bond strength values, no matter which enamel conditioner was used.