PurposeThis study was performed to evaluate the prevalence of all types and subtypes of dental anomalies among 7- to 35-year-old patients by using panoramic radiographs.Materials and MethodsThis cross-sectional study was conducted on 1649 people in Hamadan City, in 2012-2013. The prevalence of four types and 12 subtypes of dental anomalies was evaluated by two observers separately by using panoramic radiography. Dental anomalies were divided into four types: (a) shape (including fusion, taurodontism, and dens invagination); (b) number (including hypodontia, oligodontia, and hyperdontia); (c) structure (including amelogenesis imperfecta, dentinogenesis imperfecta, and dentin dysplasia); and (d) position (including displacement, impaction, and dilacerations).ResultsThe reliability between the two observers was 79.56% according to the Kappa statistics. The prevalence of dental anomalies diagnosed by panoramic radiographs was 29%. Anomalies of position and number were the most common types of abnormalities, and anomalies of shape and structure were the least in both genders. Anomalies of impaction (44.76%), dilacerations (21.11%), hypodontia (15.88%), taurodontism (9.29%), and hyperdontia (6.76%) were the most common subtypes of dental anomalies. The anomalies of shape and number were more common in the age groups of 7-12 years and 13-15 years, respectively, while the anomalies of structure and position were more common among the other age groups.ConclusionAnomalies of tooth position were the most common type of dental anomalies, and structure anomalies were the least in this Iranian population. The frequency and type of dental anomalies vary within and between populations, confirming the role of racial factors in the prevalence of dental anomalies.

PurposeThis study was performed to determine the prevalence and characteristics of pneumatized articular tubercle or eminence among a defined group of Iranian people.Materials and MethodsDigital panoramic radiographs of 1694 patients in the Department of Oral and Maxillofacial Radiology, Hamadan Dental School, Iran were evaluated retrospectively to detect the above lesion. Finally, 1563 radiographs were selected according to inclusion criteria. Then, a review was done of 10 large case series found using a MEDLINE search of the literature. Chi-squared test was used to analyze the differences in variables such as age, gender, laterality, and locularity in our case series.ResultsThe average age of our samples was 32.6±7.63 years. Pneumatized articular tubercle was found in 98 cases, representing a prevalence of 6.2% with a mean age of 22.8±7.9 and a range of 8 to 60 years. Sixty-four (65.3%) pneumatized articular tubercles were unilateral, with 30 lesions on the right and 34 on the left side. Bilateral lesions were found in 34 (34.7%) patients. 52 (53.06%) of the pneumatized articular tubercles were of the unilocular type and 46 (46.94%) were multilocular. The results showed no statistically significant differences regarding age (p=0.454), gender (p=0.634), laterality (p=0.252), or locularity (p=0.807) among the samples.ConclusionAmong ten large case series from other countries, the prevalence of pneumatized articular tubercle (6.2%) in Iranian patients was higher than that of all eight of the case series that used the same detection method as the present study of panoramic radiography.

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Knowing the anatomical relation between the posterior teeth and the maxillary sinus, help the clinician in preoperative treatment planning of the posterior maxillary teeth and avoid problems that may occur during dental practice.

Purpose Anatomical variations of the external nasal wall are highly important, since they play a role in obstruction or drainage of the ostiomeatal complex and ventilation and can consequently elevate the risk of pathological sinus conditions. This study aimed to assess anatomical variations of the nasal cavity and ethmoidal sinuses and their correlations on cone-beam computed tomography (CBCT) scans. Materials and Methods This cross-sectional study evaluated CBCT scans of 250 patients, including 107 males and 143 females, to determine the prevalence of anatomical variations of the nasal cavity and ethmoidal sinuses. All images were taken using a New Tom 3G scanner. Data were analyzed using the chi-square test, Kruskal-Wallis test, and the Mann-Whitney test. Results The most common anatomical variations were found to be nasal septal deviation (90.4%), agger nasi air cell (53.6%), superior orbital cell (47.6%), pneumatized nasal septum (40%), and Onodi air cell (37.2%). Correlations were found between nasal septal deviation and the presence of a pneumatized nasal septum, nasal spur, and Haller cell. No significant associations were noted between the age or sex of patients and the presence of anatomical variations ( P >0.05). Conclusion Radiologists and surgeons must pay close attention to the anatomical variations of the sinonasal region in the preoperative assessment to prevent perioperative complications.

BackgroundThis study aimed to compare the pharyngeal airway volume in class I,II and III skeletal malocclusion patients using cone beam computed tomography (CBCT).Material and MethodsThis retrospective, cross sectional study was conducted on lateral cephalograms of 71 patients derived from their CBCT scans. Using the ANB angle, the patients were divided into class I,II and III malocclusion. Two observers used Dolphin 3D software to calculate the pharyngeal airway volume, airway area, minimum axial area, minimum area location, airway length and morphology. Data were analyzed using one-way ANOVA, Kruskal-Wallis test, Tukey’s test, Spearman’s correlation coefficient and multiple regression analysis.ResultsThe three skeletal classes were significantly different in airway volume, minimum axial area, mean airway area and airway morphology (P<0.05). Significant differences were found in airway volume and mean airway area between class II and III patients (P<0.05). The minimum axial area and airway morphology in class III patients were greater than those in class I and II patients (P<0.05). Every one unit increase in the ANB angle decreased the airway volume by 0.261 units. The effect of ANB angle on airway volume was statistically significant and it was shown that one unit increase in the angle decreased the airway volume by 453.509 units.ConclusionsA significant correlation exists between the skeletal facial pattern and upper airway dimensions. In our study, the total airway volume and the mean airway area of class III patients were larger than those in class II patients. Key words:Cone-Beam computed tomography, malocclusion, pharyngeal airway volume.

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Background. Temporomandibular disorders (TMD) are the most common reason of non-dental pain in the orofacial region. A clinical examination of the temporomandibular joint (TMJ) with additional imaging is the most recommended procedure for TMD diagnosis. Objectives. The objective of this study was to evaluate the association between TMD and the condylar position in the glenoid fossa by examining a group of patients suffering from TMD compared with a control group of patients without TMD. In this study, we used cone-beam computed tomography (CBCT) images for measurements. Material and methods. Sixty-five symptomatic joints were selected from 48 patients with TMD. Sixtyfive joints were selected from a total of 96 asymptomatic joints in the control group. The superior, anterior and posterior area of the joint, and the steepness of the articular eminence were measured on the CBCT images. The data was analyzed using Pearson's χ 2 test. Results. The position of the condyle was significantly more posterior in the joints with TMD, and more anterior and centric in the asymptomatic joints. Statistically, the vertical position of the condyle and the steepness of the articular eminence had no significant relation with the occurrence of TMD. Conclusions. In this study, we observed that the posterior condylar position is more common in TMD patients, but it is not the reason for diagnosing TMD, and the reason of the posterior position of the condyle should be investigated before any decisions pertaining to treatment are made. In future, studies should focus on evaluating how the position of the condyle will change after the treatment of patients with TMD.