Objective:To determine the accuracy of volumetric analysis of teeth in vivo using cone beam computed tomography(CBCT).Methods: The physical volume(Vw) of 24 bicuspids extracted for orthodontic purposes(16 were imaged with the i-CAT and 8 with the CB MercuRay before extraction) was determined using water displacement technique.Corresponding pre-treatment CBCT image data were uploaded into Amira 4.0 for segmentation and radiographic volume(Va).All measurements were performed twice by two observers.The statistical difference between Vw and Va was assessed using a paired t-test.The intra-and inter-observer reliability was determined by calculating Pearson correlation coefficients and intraclass correlation coefficients(ICC).Results: The overall mean Vw of teeth specimens was 0.553?0.082 cm3,while the mean Va was 0.548?0.079 cm3,0.529?0.078 cm3 for observer 1,and 0.567?0.085 cm3 for observer 2.There were statistically significant differences between Va and Vw(P

OBJECTIVE: The aims of this study were to investigate a simple method for assessing anterior-posterior jaw relationships via cone-beam computed tomography (CBCT) images taken in the natural head position (NHP) relative to the nasion true vertical plane (NTVP), and measure normative data in Korean adults with normal profiles. METHODS: Subjects were selected from patients presenting for third molar extraction and evaluated as having normal profiles by three examiners. The CBCT images of 80 subjects (39 males, 41 females) were taken in the NHP according to Solow and Tallgren's method. Linear measurements of the A-point, B-point, and Pog were calculated relative to the NTVP. Student's t-test was used to assess sexual differences in these measurements. RESULTS: The mean linear measurements of the A-point, B-point, and Pog relative to the NTVP were 0.18 mm (standard deviation [SD], 4.77 mm), -4.00 mm (SD, 6.62 mm), and -2.49 mm (SD, 7.14 mm) respectively in Korean males, and 1.48 mm (SD, 4.21 mm), -4.07 mm (SD, 6.70 mm) and -2.91 mm (SD, 7.25 mm) in Korean females respectively. There were no statistically significant differences between Korean males and females (p < 0.05). CONCLUSIONS: Three-dimensional CBCT analysis using the NTVP is a simple and reliable method for assessing anterior-posterior skeletal relationships.
Adult* ; Cone-Beam Computed Tomography* ; Female ; Head ; Humans ; Jaw* ; Male ; Methods ; Molar, Third