title: [Severe limitation of mouth opening].
abstract: Limitation of mouth opening is a common source of referral to an orofacial pain clinic with a proposed diagnosis of Temporomandibular Joint Dysfunction (TMD). The word "trismus" is defined by the American academy of orofacial pain as: "Myospasm of masticatory muscles specifically causing limited jaw opening; early symptom of tetanus". Therefore, once trismus is suspected, TMD should be ruled out. However, it is not uncommon to find the usage of this term to describe severe limitation of opening by causes other than myospasm, therefore posing the risk of misdiagnosis. The purpose of this article is to describe the differential diagnosis of hard end limitation of opening with emphasis on the clinical tools used to differentiate between muscle source of hard end limitation and other sources of hard end limitation. Several cases of hard end limitation of mouth opening are presented and through them major principles of orofacial diagnosis are discussed.
authors.affiliation: Dept. of Occlusion and Behavioral Sciences, The Maurice and Gabriela Goldschleger School of Dental Medicine, Tel Aviv University, Tel Aviv.
authors.forename: S
authors.initials: S
authors.lastname: Reiter
authors.forename: E
authors.initials: E
authors.lastname: Winocur
authors.forename: A
authors.initials: A
authors.lastname: Gavish
authors.forename: I
authors.initials: I
authors.lastname: Eli
mesh_terms: D003937:Diagnosis, Differential; D005157:Facial Pain / Q000209:etiology; D006801:Humans; D004204:Joint Dislocations / Q000175:diagnosis; D007593:Joint Instability / Q000175:diagnosis; D008335:Mandibular Condyle / Q000473:pathology; D008410:Masticatory Muscles / Q000503:physiopathology; D009303:Nasopharyngeal Neoplasms / Q000150:complications / Q000175:diagnosis; D016059:Range of Motion, Articular; D013705:Temporomandibular Joint Disorders / Q000150:complications / Q000175:diagnosis*; D014277:Trigeminal Neuralgia / Q000175:diagnosis; D014313:Trismus / Q000175:diagnosis*