Objectives: This study was designed to evaluate effect of two different dentin pretreatment method (CPP-ACP, or CPP-ACPF) on bonding of etch-and-rinse ,and self-etch adhesives to caries-affected dentin.
Materials and Methods: A total of 90 extracted human maxillary third molar teeth with moderate carious lesions and 30 sound third molar teeth scheduled for periodontal reasons, were selected for this study. The 120 teeth were divided into four groups. 30 molars each, according to remineralizing agents application (n=30). Group A non-carious teeth as a negative control, Group B teeth with moderate caries as positive control, Group C pretreated with non-fluoridated CPP-ACP, Group D pretreated with fluoridated CPP-ACPF. Each group was subdivided into three subgroups, according to the adhesive system (n=10). After sectioning of the samples into longitudinal sticks of 1mm diameter, TBs was measured at strain rate of 0.5mm/min. Data was analyzed using Two-way ANOVA, (SPSSTM soft were), independent samples (Shapiro-wilk test, post-hoc Tukey test)
Results: Bond strength of etch-and-rinse adhesive systems to ND was significantly higher than that to CAD,CAD/CPP-ACP,CAD/CPP-ACPF. On the other hand, there was no significant difference between ND groups bonded with one step SE and two step SE adhesive systems, and that to CAD,CAD/CPP-ACP,CAD/CPP-ACPF. Untreated CAD showed the lowest TBS (P<0.05) than the other groups regardless the bonding system used .There were no significant difference between TBs of CAD, CAD/CPP-ACP, CAD/CPP-ACPF. (p < 0.05).
Conclusions:Regardless of the adhesive system used, surface pretreatment of CAD with CPP-ACP and CPP-ACPF improve bond strength . However bond strength to CAD was lower than bond strength of ND.