Evaluation of condylar positions in patients with temporomandibular disorders: A cone-beam computed tomographic study

PURPOSE: This study was performed to compare the condylar position in patients with temporomandibular joint disorders (TMDs) and a normal group by using cone-beam computed tomography (CBCT). MATERIALS AND METHODS: In the TMD group, 25 patients (5 men and 20 women) were randomly selected among the ones suffering from TMD according to the Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD). The control group consisted of 25 patients (8 men and 17 women) with normal temporomandibular joints (TMJs) who were referred to the radiology department in order to undergo CBCT scanning for implant treatment in the posterior maxilla. Linear measurements from the superior, anterior, and posterior joint spaces between the condyle and glenoid fossa were made through defined landmarks in the sagittal view. The inclination of articular eminence was also determined. RESULTS: The mean anterior joint space was 2.3 mm in the normal group and 2.8 mm in the TMD group, respectively. The results showed that there was a significant correlation between the superior and posterior joint spaces in both the normal and TMD groups, but it was only in the TMD group that the correlation coefficient among the dimensions of anterior and superior spaces was significant. There was a significant correlation between the inclination of articular eminence and the size of the superior and posterior spaces in the normal group. CONCLUSION: The average dimension of the anterior joint space was different between the two groups. CBCT could be considered a useful diagnostic imaging modality for TMD patients.

[Age assessment of developmental stages of permanent mandibular teeth using the Demirjian method]

Age estimation of the children usually is assessed using tooth developmental stages in radiographs. The Demirjian's method is one of them. This study was done with the aim of assessment of the Demirjian's developmental age stages of the permanent mandibular teeth in panoramic radiographs of 6-13 years old patients attended to Radiology Department of Mashhad dental school. In this descriptive cross-sectional study, a sample of 310 orthopantomographs taken from 169 girls and 141 boys between 6 and 13 years old referred to Mashgshad dental school was selected. The chronological age of each child was calculated by subtracting her or his birth date from the date on which the radiograph had been obtained and the developmetal stages of each of the seven left mandibular permanent teeth were recorded using the Demirjian method. Independent-sample t test was applied for comparison of the mean age of different developmental stages in both genders. The mean chronological age of stage G of teeth 32 and 33, stage F of tooth 34 and stages D and F of tooth 35 was different between the two genders [P<0.05]. The mean chronological age of teeth 31, 36 and 37 in both sexes and in different developmental stages showed no statistically significant difference [P>0.05]. The mean ages of different developmental stages of permanent mandibular teeth using the Demirjian method were similar to former studies. Also, the stage of mandibular teeth development was higher in girls than boys with similar chornological ages