ABSTRACT
Introduction: hyperplasia of the coronoid process of the mandible is a rare developmental anomaly and may be unilateral or bilateral. Unilateral enlargement of the coronoid process can result from a true tumor, such as an osteochondroma or osteoma. The purpose of this case report is its abnormal sits as well as rarity
Results and discussion: an enlarged coronoid process impinging on the posterior surface of the zygoma restricting mandibular opening and facial asymmetry and fracture of zygomatic arch was detected. Coronoidectomy was done for the patient under general anesthesia via an intraoral approach
Conclusion: one of the differential diagnosis of restricted mandibular opening is coronoid process hyperplasia. Treatment of coronoid hyperplasia consists of surgical removal of the enlarged coronoid process or processes to allow freedom of mandibular motion. Coronoidectomy is usually accomplished via an intraoral approach. Conventional radiographic techniques do not fully reveal the size and mushroom-shaped coronoid process, so CT Scanning and tomography is suggested