[An X-ray study of the incidence of asymptomatic hypertrophy of the coronoid process].

Although the coronoid process is not part of the temporomandibular joint, hyperplasia of the coronoid process can effect the mandibular movement as the result of the impingement on the zygomatic arch which is demonstrated in the case of a 22-year-old man. In order to access the prevalence of the asymptomatic enlargement of the coronoid process we carried out an investigation on 2000 panoramic radiographs and found only one case of a 64-year-old man. The very rare coronoid process abnormalities demonstrated on routine plan films should best be demonstrated in computed tomography, appreciating the morphology and the deformity of the surrounding structures.