Comparative evaluation of the effect of intracanal medicaments calcium hydroxide, modified triple antibiotic paste, and Bio-C Temp on root dentin microhardness: An in vitro study

Abstract Aim: The present study aimed to evaluate and compare the effects of three intracanal medicaments – calcium hydroxide (Ca(OH) 2 ), modified triple antibiotic paste (MTAP), and Bio-C Temp – on the microhardness of root dentin. Materials and Methods: Twenty extracted mandibular premolars with single canals were decoronated and standardized to 14 mm length. Following biomechanical preparation using ProTaper rotary instruments, the specimens were randomly allocated into four groups: Ca(OH) 2 , MTAP, Bio-C Temp, and a control group without medicament. The medicaments were placed using a lentulospiral and the canals sealed. All samples were incubated at 37°C in 100% humidity for 14 days. Mid-root dentin discs of 2 mm thickness were obtained and microhardness was assessed using a Vickers hardness tester under a 200 g load for 15 s. Statistical Analysis: Data were analyzed using the Kruskal–Wallis test, followed by one-way ANOVA and Tukey’s post hoc pairwise comparisons. The significance level was set at 5%. Results: MTAP produced the greatest reduction in dentin microhardness, followed by Ca(OH) 2 , while Bio-C Temp showed the least reduction. The control group exhibited the highest values. Differences among groups were statistically significant, except between Bio-C Temp and the control group. Conclusion: Bio-C Temp preserved dentin microhardness more effectively than Ca(OH) 2 and MTAP, indicating its potential as a favorable intracanal medicament with minimal adverse structural effects.