Effects of saliva contamination on shear bond strength of compomer to dentin in primary teeth

Purpose : To investigate the effects of saliva contamination on the bond strengths of two compomers applied to primary teeth dentin during different bonding stages. Methods: 30 extracted human non-carious primary molars were prepared for shear bond-strength testing. Specimens were randomly divided into three groups of 10. Prime & Bond NT (acetone-based) and Futura Bond A & B (water-based) adhesives were tested under the following conditions: (a) non-contaminated conditions; (b) after contamination of the dentin surface with fresh whole saliva for 20 seconds and removal of excess saliva before adhesive application; and (c) contamination of the dentin surface with fresh whole saliva for 20 seconds and removal of excess saliva after adhesive curing. Following adhesive application Dyract AP or Glasiosite was applied via a polytetrafluroethylene split mould and light-cured to the dentin surface. Shear bond strengths were measured using an Instron Universal testing machine running at a crosshead speed of 1 mm/minute. After measuring shear bond strengths, specimens were prepared for SEM evaluation and identification of failure type. Results were analyzed by two-factor experiment with repeated measures as one factor. Results: No statistically significant differences were found among the shear bond strengths (P > 0.05) of the groups. The results revealed that saliva contamination of dentin surfaces before or after adhesive application did not affect the shear bond strength of either compomer.