Comparison of gonial angle determination from cephalograms and orthopantomogram

Abstract

Introduction:Gonial angle is an important parameter of the craniofacial complex giving an indication about the vertical parameters and symmetry of the facial skeleton. Both orthopantomogram (OPG) and lateral cephalograms can be used for the measurement of gonial angle. Because of the superimpositions seen on lateral cephalograms, reliable measurement of the gonial angle becomes difficult. The aim of the present study is to check the possible application and reliability of OPG for gonial angle determination by clarifying whether there is any significant difference between the determination of gonial angle from OPG and cephalogram.Materials and Methods:Gonial angle measurements were made on lateral cephalograms and orthopantomograms of 98 patients - 44 males (mean age 25.9 years) and 54 females (mean age 21.3 years), and compared using Statistical Package for Social Sciences.Results:One-way analysis of variance demonstrated no significant differences between the values of gonial angles determined by lateral cephalogram and panoramic radiography. Pearson correlation showed a high correlation between cephalometric and OPG gonial angle value.Conclusion:Panoramic radiography can be used to determine the gonial angle as accurately as a lateral cephalogram. For determination of the gonial angle, an OPG may be a better choice than a lateral cephalogram as there are no interferences due to superimposed images of anatomical structures as in a lateral cephalogram. Thus, the present study substantiates the possibility of enhancing the clinical versatility of the panoramic radiograph, which is an indispensable tool for dental diagnosis.

Dilemma of gonial angle measurement: Panoramic radiograph or lateral cephalogram

“…The mean values of the right and the left gonial angles measured using the panoramic radiographs also did not show a statistically significant difference. The results of this study were in accordance with the findings of Larheim et al5 and Bhullar et al,12 who reported no statistically significant differences in the gonial angle measured using lateral cephalograms and panoramic radiographs. Mattila et al7 measured the gonial angle using panoramic radiographs and lateral cephalograms, compared the values with those found using dry skulls, and concluded that the measurements made using the panoramic radiographs were more accurate, which is contrary to the findings of the present study.…”

Comparison Between Three Methods of Gonial Angle Formation on Lateral Cephalogram and Orthopantomogram

“…13,[14][15][16] Several researcher's have compared the two types of radiographs for predicting cephalometric gonial angle. [17][18][19][20][21][22] Ul Haq MH / Memon S / Agha D Bibi T in their study reported significant correlation between the cephalometric and panoramic values and concludes that panoramic radiography is as reliable as lateral cephalogram in predicting vertical facial pattern as assessed by gonial angle. 18 In an other study statistically insignificant difference was found in the gonial angle measured by two different radiographic methods in three different types of occlusion.…”

Comparative analysis of the gonial angle on lateral cephalometric radiographs and panoramic radiographs

“…However, as compared with LCR, PR is not yet reliable enough to provide sufficiently accurate additional information (4). In addition, no reports have specified a detailed method for drawing the inferior border of the mandible (9,(11)(12)(13)(14)(15)(16)(17)(18)(19)(20). Thus, the important points for tracing on film were reviewed in this report.…”

“…It is important to evaluate the similarity of the GA on PR and LCR. PR has several advantages over LCR, including the ability to evaluate mandibular asymmetry (4,12) and mandibular growth direction (2-4,35,36), the separate and clear measurement of both the right and left GA (12,20), relatively low radiation exposure (37)(38)(39), and the possibility of greater clinical versatility. It has been reported that the GA is wider for edentulous persons than for dentate individuals (6-11), perhaps because of morphological changes secondary to tooth loss.…”

“…Many studies have evaluated the GA on PR, but no previous report described how to produce accurate, detailed images of the GA (9,11,(12)(13)(14)(15)(16)(17)(18)(19)(20). It is essential to develop a detailed method for drawing the inferior border of the mandible-in which only one line is made on the inferior border of the mandible-so as to not change the condition of the GA. Additionally, if the GA on PR is anatomically similar to the GA on LCR or has a characteristic structure, PR may prove to be more useful and could become a high-value-added dental examination.…”