Mandibular coronoid process hyperplasia leading to restricted mouth opening: a case report

doi:10.19438/j.cjoms.2026.01.015

Abstract

Abstract: Coronoid process hyperplasia(CPH) is a rare disorder of mandibular development, mainly characterized by painless progressive limitation of mouth opening, which is easily confused with temporomandibular joint disorder(TMD). This article reported a case of severe mouth opening limitation caused by bony hyperplasia of the coronoid process. After coronoidotomy via an intraoral approach, the mouth opening degree was significantly improved. For patients with clinical manifestations of painless mouth opening limitation, the possibility of CPH should be considered, and CBCT examination should be performed as early as possible to avoid misdiagnosis.

Key words: Coronoid process hyperplasia, Mandibular coronoid process hyperplasia, Limitation of mouth opening, Coronoidotomy

CLC Number:

R782.2

Jin Wenzhao, Xu Kai. Mandibular coronoid process hyperplasia leading to restricted mouth opening: a case report[J]. China Journal of Oral and Maxillofacial Surgery, 2026, 24(1): 96-99.

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