1.Professor and Head, Department of Conservative Dentistry and Endodontics, Sri Hasanamba Dental college
2.Professor, Department of Conservative Dentistry and Endodontics, Sri Hasanamba Dental college
3.Professor, Department of Conservative Dentistry and Endodontics, Sri Hasanamba Dental college
4.Assistant professor, Department of Conservative Dentistry and Endodontics, Sri Hasanamba Dental college
5.Post Graduate Student, Department of Conservative Dentistry and Endodontics, Sri Hasanamba Dental college
Background: In endodontics, adequate chemo-mechanical preparation is required for complete disinfection root canals. HEBP (Etidronate) is a gentle chelating agent that helps remove the smear layer and reduce debris buildup. It can be used with sodium hypochlorite (NaOCl) in a method called continuous chelation. This allows both cleaning and smear layer removal without weakening the disinfecting effect of the hypochlorite. Calcium hypochlorite is a good alternative to NaOCl. It has strong antimicrobial and tissue-dissolving abilities, with more available chlorine and better shelf life.
Aim: To evaluate and compare the effect of different concentrations of HEBP and calcium hypochlorite on micro hardness of root canal dentin.
Materials and Methodology: Forty single-rooted teeth were collected and then decoronated below the CEJ using a diamond disc Forty root halves were prepared by longitudinal splitting of forty extracted mandibular premolars and embedded in autopolymerizing acrylic resin, leaving the dentin surface exposed. After polishing, the groups were then divided into 5 groups of 8 samples(n=8) each through random sampling. Then samples were surface treated for 5 minutes with 5 ml of one of the following irrigants, Saline (control group) (n=8), 9% HEBP solution (n=8), 18% HEBP solution (n=8), 5% CaOCl2 solution (n=8), 10% CaOCl2 solution (n=8). After surface treatment, the microhardness values of dentin were recorded by using Vickers tester at the mid-root level.
Results: 10% Calcium Hypochlorite demonstrated the highest reduction in root canal dentin microhardness. 18% HEBP induced a moderate yet statistically significant decrease in dentin microhardness. 9% HEBP and 5% Calcium Hypochlorite exhibited the least impact, indicating minimal aggressiveness toward dentin
Conclusion: Within the limits of this study, all tested irrigants.9% HEBP, 18% HEBP, 5% Ca(Ocl)2, and 10% Ca(Ocl)2—significantly reduced the microhardness of root canal dentin after 5 minutes of exposure.
Among them, 9% HEBP caused the least reduction, suggesting it may better preserve dentin hardness compared to higher concentrations of HEBP and calcium hypochlorite solutions.
