title: Timing interventions in relation to temporomandibular joint closed lock duration: a systematic review of 'locking duration'.
abstract: Temporomandibular joint (TMJ) 'closed lock' (CL) is a clinical condition causing TMJ pain and limited mouth opening (painful locking) that is mostly attributed to disc displacement without reduction (DDwoR), or less commonly to anchored disc phenomenon (ADP). Both conditions are described clinically as CL that can be 'acute' or 'chronic' depending on the duration of locking. There is, however, no consensus about the duration of locking that defines the acute state and its effect on the success of interventions. This review paper, therefore, aims to provide: (i) a narrative review of the pathophysiological need for early intervention in DDwoR and the clinical implications of acute/chronic CL stages on the management pathway; (ii) a systematic review investigating the effects of locking duration on the success of interventions for CL management. Electronic and manual searches until mid-August 2013 were conducted for English-language studies of any design investigating the effects of non-surgical and surgical interventions for acute or chronic CL (DDwoR or ADP). A total of 626 records were identified, and 113 studies were included. Data extraction and quality assessment were completed for all included studies. Included studies were, however, heterogeneous and mostly of poor-quality leading to contradictory and inconsistent evidence on the effect of the duration of locking on treatment outcomes. Future high-quality trials investigating the effect of CL duration on treatment outcome are needed. At present, early intervention by 'unlock' mandibular manipulation seems to be the most practical and realistic approach that can be attempted first in every CL patient as an initial diagnostic/therapeutic approach.
authors.affiliation: Department of Oral and Maxillofacial Surgery, School of Dental Sciences, Newcastle University, Newcastle upon Tyne, UK.
authors.forename: M
authors.initials: M
authors.lastname: Al-Baghdadi
authors.forename: J
authors.initials: J
authors.lastname: Durham
authors.forename: J
authors.initials: J
authors.lastname: Steele
mesh_terms: D005157:Facial Pain / Q000209:etiology* / Q000503:physiopathology; D005260:Female; D006801:Humans; D008297:Male; D010147:Pain Measurement; D016059:Range of Motion, Articular; D013704:Temporomandibular Joint / Q000503:physiopathology*; D019224:Temporomandibular Joint Disc / Q000503:physiopathology; D013706:Temporomandibular Joint Dysfunction Syndrome / Q000150:complications* / Q000503:physiopathology*; D013997:Time Factors; D016896:Treatment Outcome
keywords: acute closed lock; chronic closed lock; disc displacement without reduction; jaw locking; locking duration; temporomandibular joint