Linear and Angular Mandibular Measurements: Comparison Between Panoramic Radiography (Orthopentomogram) And Lateral Cephalogram

Abstract

Invention of lateral cephalogram by Hofrath in Germany and Broadbent in United States provided a clinical tool for assessment of skeletal disparities. But lateral cephalogram is not effective in measuring bilateral cranial structures independently. In orthodontic practice, panoramic radiographs are frequently obtained for information about maturation period of teeth with surrounding tissues and their axial inclination. Objective: To determine the use of orthopantomogram, whether it’s a substitute of lateral cephalogram for the linear and angular measurement of mandible. Methods: This was a Prospective Cohort study. Study was conducted at Nishtar Institute of Dentistry, Multan form January 2021 to December 2021 in one year duration. A total of 75 patients were found to be eligible for the study. Gonial angle of patients with malocclusion type I was measured with lateral cephalogram and orthopantomogram. In orthopantomogram, measurement of gonial angle was made by drawing a tangent line to the lower border of mandible and other tangent line to the distal border of ramus and both sides of condyle. In lateral cephalogram it was measured at intersection point of mandibular plane and ramus plane. Results: Overall, 75 patients were included in our study. The average age of the patients was 16.43±4.06 years. The mean difference between cephalogram and OPG was statistically significant, (p<0.001). Conclusions: Gonial angle can be measured on OPG as accurately as on lateral cephalogram but linear measurements are taken accurately by the help of orthopentomogram.