Multiparameter image analysis to evaluate dentinal tubules patency after using different irrigation protocols

Background: Scoring systems have been used to evaluate dentinal tubule patency in several papers; however, these conventional systems are time-consuming and rely primarily on evaluator estimation with a wide range of subjective variations. Objectives: A multiparameter, simple, and objective method is introduced to evaluate the ability of different irrigation protocols for smear layer removal and dentinal tubule patency enhancement. To show the applicability of this method, the effect of different irrigation regimens was evaluated. Methods: Ninety extracted single-rooted teeth were decapitated and shaped with ProTaper to size F4. According to the final irrigation protocol, specimens were divided into three groups: Group 1 (final irrigation of SmearOFF), Group 2 (17% EDTA), and Group 3 (negative control). Groups 1 and 2 were subdivided into two subgroups: Subgroup (A) was activated by an ultrasonic file, whereas samples in Subgroup (B) did not receive any activation. Samples were examined by scanning electron microscopy. Images were analyzed using ImageJ software, and the multiparameter image analysis method (relative total surface area, average size, and the number of opened dentinal tubules) was applied. One-way analysis of variance (ANOVA), followed by Tukey’s post hoc test, was applied to reveal any significant differences (P < 0.05) among groups, activation techniques, and root thirds. Results: Passive ultrasonic activation led to a significant increase in the patency of dentinal tubules especially at the apical third, which was measured and shown by the triple parameter method. Conclusion: Digital image analysis shows potential and advantages for the objective evaluation of dentinal tubules and should replace the traditional subjective scoring system method.