Patients with suspected unilateral condylar hyperplasia are often screened radiologically with a panoramic radiograph, but this is not sufficient for routine diagnosis and follow up. We have therefore made a quantitative analysis and evaluation of panoramic radiographs in a large group of patients with the condition. During the period 1994-2011, 132 patients with 113 panoramic radiographs were analysed using a validated method. There was good reproducibility between observers, but the condylar neck and head were the regions reported with least reliability. Although in most patients asymmetry of the condylar head, neck, and ramus was confirmed, the kappa coefficient as an indicator of agreement between two observers was poor (−0.040 to 0.504). Hardly any difference between sides was measured at the gonion angle, and the body appeared to be higher on the affected side in 80% of patients. Panoramic radiographs might be suitable for screening, but are not suitable for the quantitative evaluation, classification, and follow up of patients with unilateral condylar hyperplasia.