CONE-BEAM COMPUTED TOMOGRAPHY AND LIGHT MICROSCOPIC EXAMINATION OF HUMAN EXTRACTED MOLARS — AN IN VITRO STUDY

Purpose: The aim of this in vitro study was to examine the distinct types of isthmuses using a light microscope and cone-beam computed tomography (CBCT). Material/Methods: Fifty-five extracted human molars were used for this study. CBCT was used to conduct the study. After the CBCT analysis, all teeth were inspected under a light microscope, and the results were compared with those of the CBCT examination. Results: The results from the CBCT at the coronary third of the root canals were as follows: Types I, II, III, IV, and V isthmuses were found in 50.9%, 16.4%, 1.8%, 7.3%, and 23.6% of all samples, respectively. For the middle third, we found Types I, II, III, IV, and V isthmuses in 40.0%, 23.6%, 1.8%, 16.4%, and 18.2% of the samples, respectively. For the apical third, we identified Types I, II, III, IV, and V isthmuses in 60.0%, 29.1%, 5.5%, 1.8%, and 3.6% of all samples, respectively. The results obtained from the microscopic examination were similar to those from the CBCТ study. There is no confirmed statistically significant difference between the examination methods (p = 0.07). Conclusion: Three-dimensional examinations have a significant role among the methods for diagnosing and detecting an isthmus in the complex root canal system, especially in the apical part.