A comparative evaluation of cone-beam computed tomography and multi-slice computed tomography in the diagnosis of sheep mandibular bone defect: an in vitro study

Introduction: Diagnosis of lesions and bone defects is very important and there is a lack of substantial studies on the most appropriate method for bone defect measurement. Hence, the aim of this study is to evaluate the accuracy of multi-slice computed tomography (MSCT) and cone-beam computed tomography (CBCT) in the diagnosis of mandibular bone defects present in sheep. Material & Methods: This in vitro study was performed on 15 sheep's mandibular bones. Some defects were created in cortical and spongy bone using high-speed hand piece at the buccal and lingual cortical bone of the lower jaw. Totally, 75 mandibular bone defects with a depth of 1-3 mm were created. The mandibular bone samples were scanned using MSCT and CBCT scanners, and these scans were evaluated by two oral and maxillofacial radiologists. The positive and negative predictive values, sensitivity and specificity were calculated for both methods. Results: The sensitivity of MSCT and CBCT were 78% and 96.5% and  Specificitiey of MSCT and CBCT were 90% and 92% respectively. The positive and negative predictive values were 97.5% and 89.5 % for CBCT, and 90% and 92% for MSC respectively. The negative and positive likelihood ratios (LR-) and (LR+) were 0.035 and 13.04 for CBCT as well as 0.245 and 7.82 for MSC respectively. Conclusion: The study results demonstrated a higher accuracy of CBCT, compared to MSCT, in the diagnosis of bone defects.