Ehsan Moudi, Sina Haghanifar, Kaveh Kazemian, Ramin Foroughi, Mehrdad Nabahati, Ali Bijani,
Volume 7, Issue 2 (9-2018)
Abstract
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.
Materials & 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.
Nedasadat Tavoosi, Mehdi Rafiei, Eilnaz Ehrami, Nasim Jafari Pozveh,
Volume 12, Issue 1 (3-2023)
Abstract
Introduction: After the third molars, the maxillary canines are the most frequently impacted teeth. Sella turcica bridging (STB) can be used as a predictive factor to help orthodontists in early diagnosis. The aim of this study was to investigate the relationship between palatal canine impaction (PCI) and STB.
Materials & Methods: In this case-control study, in available lateral cephalograms and panoramic radiographs of 53 patients with PCI and 53 controls with normal dentition and no impacted canines the dimensions of STB were measured and graded. Grade I (no calcification): The length of the sella is greater than ¾ of its diameter.Grade II (partial calcification): The length of the sella is equal to or less than ¾ of its diameter.Grade III (complete calcification): A separation bridge is clearly visible on the radiograph. The patients and controls were between 12 and 20 years of age. The relationship between STB and PCI was analyzed using the Chi-square test, Mann-Whitney test, and Fisher’s exact test. A value of P<0.05 was considered significant.
Results: There was a significant relationship between STB and PCI (P<0.001). A significant relationship was also found between STB severity grade and PCI (P<0.001). The probability of the presence of Grade II STB in patients with PCI was three times higher than in those with normal dentition. The probability of the presence of Grade III STB in patients with PCI was approximately 46 times higher than in individuals with normal dentition. The length: diameter ratio of the sella turcica was not significantly different between the two groups of patients and controls. No significant relationship was found between gender and STB.
Conclusion: The relationship between STB and PCI could be used as diagnostic early indicator to confirm PCI.
