Efficacy of Different Reagents to Prepare Transparent Tooth Model for Three Dimensional View of the Root Canal System- An Invitro Study

Abstract

Introduction: There are certain common as well as atypical characteristics in the root canal anatomy of each tooth. Simultaneous understanding of both can be the key to successful endodontics. Various methods have been used till date for visualisation of root canal morphology with variable success rates like magnification, radiography, CBCT, digital imaging and clearing. Clearing technique provides a three-dimensional view of the root canal anatomy from outsidewhile maintaining the original form and relationship of canals as minimal instrumentation is required in the procedure. It is a simple and inexpensive technique which involves decalcification of tooth structure, dehydration in alcohol and clearing by immersing in clearing agents. Aim: This study aimed to evaluate the efficacy of two decalcifying agents (nitric acid and trichloroacetic acid) and two clearing agents (methyl salicylate and eugenol) in the preparation of transparent tooth model for viewing the root canal system. Materials and Methods: The in-vitro research study from August 2, 2019 to August 27, 2019 included 40 freshly extracted teeth (18 maxillary and 22 mandibular) which were randomly divided in two groups (n=20); group A (decalcification done in 5% nitric acid) and group B (decalcification done in 10% trichloroacetic acid). Then, the teeth were dehydrated in isopropyl alcohol. Each group was subdivided in two subgroups depending on the clearing agent used (methyl salicylate or eugenol). Afterwards they were graded for transparency and haziness criteria, and data analysis was done using chi-square test, value of significance at p<0.05. Results: The results showed that nitric acid took lesser time for decalcification than trichloroacetic acid. The subgroup 1 (NA/MS) showed better transparency level in 90% of the samples when compared with other subgroups; however the results were not significant with p-value 0.121. Haziness was present in all samples. The subgroup 4 (TCA/E) showed 100% haziness which was statistically significant among all the subgroups with p-value 0.002. Methyl salicylate showed better transparency, less haziness and good root canal morphology when compared with eugenol. Conclusion: Nitric acid when used in combination with methyl salicylate prepared the best transparent tooth model. Trichloroacetic acid showed average transparency and haziness was present in almost all the samples irrespective of the clearing agents used.