Comparison between the external gonial angle in panoramic radiographs and lateral cephalograms of adult patients with Class I malocclusion

Abstract

The external gonial angle is an important angle of the craniofacial complex. It is significant for the diagnosis of craniofacial disorders. Lateral cephalogram and orthopantomograms can be used to determine this angle. In this study, we compared the external gonial angle determined from the two mentioned radiographs in Class I patients. We collected the radiographs of 70 patients with Angle's Class I (22 men and 48 women). The patients' age ranged from 15-30 years with a mean age of 18.24 years. The data gained were statistically evaluated by t-test. The following results were obtained. The mean value of the gonial angle in the lateral cephalogram was 125.00 degrees (men, 124.9 degrees and women, 125.04 degrees ) and in the orthopantomogram was 124.17 degrees (men 123.68 degrees , women 124.39 degrees ). The difference between these rates was 0.83 degrees (men 1.22 degrees , women 0.64 degrees ) and not significant (P = 0.406). Based on the obtained results, we can conclude that panoramic radiography can be used to determine the gonial angle as accurately as a lateral cephalogram. In addition, we can determine the right and left gonial angles of a patient in the orthopantomogram without interferences due to superimposed images of anatomical structures in a lateral cephalogram. For determination of the gonial angle, an orthopantomogram may be a better choice than a lateral cephalogram.

Relationship between maximum bite force and the gonial angle in crossbite

“…Evidence shows that irrespective of whether GA measurements are obtained by lateral teleradiography or panoramic radiography, the results are compatible [23][24][25]. However, no records of GA measurements directly on the face of the individual, as in the method adopted by our study, were found.…”

“…We did not find studies that performed GA evaluation directly on the face in the literature; however, in studies where the measurements were performed on radiographies, the values were 124.17 [24], 123 [23] and 127.07 [25] degrees. The comparison between GA values obtained by direct measurement or radiographies is not the purpose of this study; however, the proximity found is an important finding, since it gives credibility to the direct measurement on the face.…”

Sex determination by using mandibular ramus: A digital radiographic study

“…[5] The brightness and contrast enhancement and enlargement of the images provide an reproducible method of measuring the chosen points. [6,7] The measurements taken from mandibular ramus are subjected to linear discriminant function.…”

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.…”

“…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.…”