# An Evaluation of the Ramus Mandibular Asymmetry on the Panoramic Radiography
Although the CBCT remains the golden standard imagistic technique [15; 16; 17] and it is considered the most appropriate imaging method for the evaluation of bone structures, the high level of radiation poses a potential risk, especially for children [18; 19; 20]. The use of panoramic radiographs to evaluate side-to-side differences is equivocal, as it has been shown that there is magnification in both vertical and horizontal planes. To prevent magnification in the vertical direction, the distance between the focal point of the X-ray tube and the film must always be the same [21; 22]. Despite the fact that panoramic radiography has low resolution and is affected by magnification, image distortion, and the superposition of different anatomic structures, in many studies on facial asymmetry, condylar or ramal asymmetry is determined using panoramic radiography [23; 24; 25; 26; 27; 28; 29; 30]. These studies have assessed the reliability and validity of panoramic radiographs for measuring condylar and ramal asymmetry. We have to take into account that the vertical component of the structures that appear on the panoramic radiographs is less subject to distortion due to their posterior positioning compared to the anterior ones. Some authors have suggested that good-quality panoramic radiographs yield acceptable results with acceptable reproducibility, are non-invasive and have a favorable cost-benefit relationship [17; 31; 32; 33; 34; 35; 36; 37; 38; 39]. In order to assess validity, [PERSON] concluded that the patient's head must be centered in the head holder when a clinical panoramic radiography is to be evaluated, and they were the first researcher to suggest using an asymmetry index, comparing vertical differences between the left and right condyles and rami. By changing the position of the mandible horizontally 10 mm or less, the vertical difference can be changed to less than 6%. They deemed asymmetry as being relevant when the asymmetry index was higher than 3%, which was accompanied by a difference of 6% between vertical mandibular condyles and rami, thus pointing to genuine vertical asymmetry. Habets only provides an index that helps observe the differences in height between the left and right condyle [31; 32]. In the horizontal plane, the distortion between the left and right sides depends on the position of the patient's head, and it was suggested that the mesiodistal widths of the mandibular first molars should be bilaterally compared to evaluate horizontal distortions in panoramic radiographs [34]. The early diagnosis of mandibular asymmetry is essential for preventing and intercepting asymmetry and choosing efficient therapeutic actions so as to avert its consequences [40; 41]. A cross-sectional study was conducted on a group of 214 subjects (134 females and 80 males) with an age range of 7-15 years. The evaluation of mandibular posterior vertical asymmetry was performed using panoramic radiography for the subjects in the studied group. The asymmetry indexes were calculated according to the method of Habets. Later, the percentage of asymmetry was calculated for the condyle (CAI), ramus (RAI) and condyle-plus-ramus (MAI) in different types of malocclusions (Angle Cl I, Cl II/1, Cl II/2, Cl III and UPC), taking into account the sexual dimorphism. Early asymmetries of the condyle were observed in both genders. The obtained results showed us that this method could easily be used clinically, providing information about the mandibular asymmetry stage of each patient before the start of orthodontic treatment.