SNA and SNB measurements: A comparative assessment between measurements in conventional 2D cephalogram and 3D cone-beam computed tomography-generated values
Bikash Ranjan Das1, Pradeep Jain2, Nikita Modi3, Priyanka Soni4, Dipayan Datta5, Adrika De6
1 Command Military Dental Centre (Western Command), Chandigarh, India
2 Department of Orthodontics and Dentofacial Orthopaedics, College of Dental Sciences, Rajasthan University of Health Sciences, Jaipur, Rajasthan, India
3 Private Practitioner, Guwahati, Assam, India
4 Medical Officer (Dental), Jodhpur, Rajasthan, India
5 Department of Public Health Dentistry, Triveni Institute of Dental Sciences, Hospital and Research Centre, Bilaspur, Chhattisgarh, India
6 Department of Oral Medicine and Radiology, New Horizon Dental College and Research Institute, Bilaspur, Chhattisgarh, India
Dr. Bikash Ranjan Das
Command Military Dental Centre (Western Command), Chandigarh.
Source of Support: None, Conflict of Interest: None
Background: The aim of the investigation was to clearly locate subspinale (point A) and supramentale (point B) on three-dimensional (3D) cone-beam computed tomography (CBCT) images and to compare the angular and linear measurements that are dependent on these anatomic landmarks with two-dimensional (2D) manual and digital cephalometric tracings. Materials and Methods: A sample of 30 North Indian subjects between 13 and 22 years of age who required CBCT imaging for treatment planning was taken. For each patient, standardized film and digital cephalograms were taken. Standardized head positioning was done for CBCT imaging. The following four groups were evaluated for statistical analysis: Group 1: Dolphin, Group 2: CBCT, Group 3: Manual tracing 1, and Group 4: Manual tracing 2. Analysis of variance was applied to find out the differences in parameters among groups. Results: The results showed that the differences between most of the measurements derived from the landmarks identified on film and digital 2D cephalometric radiographs compared with CBCT-derived cephalograms were statistically significant. Point A, which is difficult to locate on 2D cephalograms, could be identified and measured accurately and more reliably on 3D CBCT-generated cephalograms. Conclusion: 3D CBCT-generated cephalograms can be successfully used for accurate and reliable cephalometric analyses.