The mandibular symmetry is essential to determine the patterns, not only of facial beauty, but also in the masticatory function. The growth and development alterations, genetic pathologies, traumatic, neoplasic or the characteristics of each population, that affect the jaw, generate consequences that may lead to even surgical treatments for correction. Thilander analysis on panoramic x-rays, allows the assessment of the magnitude of mandibular asymmetries, as part of the complementary exams in the diagnostic process. The objective of the study was to determine the frequency of condylar asymmetries in mandibular body and ramus in digital panoramics x-rays. A cross- sectional study was carried out in 500 digital panoramic x-rays with adequate contrast and density, obtained from patients over 18 years of age, with full dentition. Sex and age were registered by 9.1 CliniView program. Proposed mandibular measurements were recorded by Thilander, calculating the differences with the Bazzur’s formula. The prevalence of pathological condylar asymmetries in the population over 18 years is 6 %. A significant difference was found in the vertical measurements between the two sides, though there was no influence by either sex or age. The differences in the height of the mandibular ramus are, in most cases, at the expense of the condyle. The discrepancies between the left and right sides must be considered as diagnostic element in possible articular pathologies.

KEY WORDS: Panoramic Radiography; Asymmetries; Condyle; Mandibular branches; Thilander.