Method:
Ten roots of human maxillary incisors and ten roots of bovine incisors were prepared until #80 k-files and #180 k-files for human and bovine roots respectively, using Crown-down technique. Irrigation was done with 1% NaOCl at each change of instrument and a final rinse with 17% EDTA. The specimens were filled with AH plus sealer and gutta-percha cones. Roots were sectioned to obtain 1-mm-thick slices from cervical, middle and apical canal thirds. After 24 h, slices were submitted to push-out test in universal testing machine, using specific points for each canal third of both substrates. Data (MPa) were submitted to two-way ANOVA, considering substrate and root canal thirdas independent variables. Post-hoc analysis was done using Tukey test (α=0.05). Failure types were recorded.
Result:
Significant differences were found for the bond strength values between bovine- (0.35±0.08) and human-root dentin (0.93±0.62) (p<0.05). No significant differences were found for root canal thirds(p>0.05) as well as for the interaction between factors (p>0.05). Adhesive failures predominated in both groups.
Conclusion:
Although the bond strength of human teeth was superior than bovine teeth, both substrates have the same performance in all the root canal thirds. This indicates that bovine teeth might be a substitute to human counterparts in push-out strength tests.