Effect Of Surface Cleaner On Bond Strength In Contaminated Samples

This in vitro study aimed to assess the effect of a "surface cleaner" on the micro-shear bond strength (μSBS) of resin composite restorations to dentin surfaces contaminated with saliva at various stages of the adhesive procedure, using a two-step self-etch adhesive system. A total of 140 extracted human molars were randomly assigned to 14 groups(n=10), each representing different stages of salivary contamination and decontamination protocols. In selected groups, a Surface Cleaner was applied in different steps (before primer, after primer, after bond application, and after bond polymerization). A two-step self-etch adhesive system and a composite resin were used for the restorations. After 24-hour water storage, μSBS testing was performed. Failure modes were assessed using a stereomicroscope, and dentin surfaces of 14 groups were analyzed under Scanning Electron Microscopy. Data were statistically evaluated using one-way ANOVA and LSD post hoc tests (p<0.05). Statistically significant differences were observed among the groups (p=0.029). The highest bond strength was recorded in the group where contamination occurred after primer application and was followed by surface cleaner application (29.5 ± 9.25 MPa). Improved values were also observed when decontamination occurred after the polymerization of bond. Within the limitations of this in vitro study, surface cleaner showed potential to reduce the negative impact of salivary contamination on bond strength, particularly when applied after primer or bond polymerization. Further studies are recommended to confirm these findings and evaluate their clinical relevance.