title: Orthopedic jaw movement observations. Part II: The rotational capacity of the mandible.
abstract: Using computerized axiography, particularly the electronic mandibular position indicator (EMPI), the mandibular opening movement was measured in 86 asymptomatic volunteers and temporomandibular joint (TMJ) patients. Terminal hinge-axis movement and hinge-axis rotation at maximum-guided mouth opening were recorded. The angle of hinge-axis rotation was used as a parameter for both movements, in accordance with the neutral-zero method. This is a well-established technique in orthopedics and is the standard tool for quantitative functional analysis of joints. An average group was defined, 50% being volunteers. The interquartile range for terminal hinge-axis movement in this study was 5.42 degrees-7.41 degrees in the volunteers and 4.73 degrees-7.25 degrees in the patients. The interquartile range for hinge-axis rotation at maximum opening was from 29.09 degrees-34.87 degrees in the volunteers and from 26.7 degrees-35 degrees in the patients. Computerized axiography is a refined tool for analyzing rotational and translational capacities of the mandible. It is a valid and practical method for orthopedic-diagnostic evaluation of mandibular movements and gives objective criteria for diagnosis in accident victims.
authors.affiliation: Dental Clinic, Department of Removable and Fixed Prosthodontics, University of Vienna, Austria.
authors.forename: E
authors.initials: E
authors.lastname: Piehslinger
authors.forename: R M
authors.initials: RM
authors.lastname: Celar
authors.forename: T
authors.initials: T
authors.lastname: Horejs
authors.forename: R
authors.initials: R
authors.lastname: Slavicek
mesh_terms: D000293:Adolescent; D000328:Adult; D002648:Child; D005260:Female; D006801:Humans; D007574:Jaw Relation Record / Q000379:methods*; D007593:Joint Instability / Q000503:physiopathology; D008297:Male; D008334:Mandible / Q000502:physiology* / Q000503:physiopathology*; D008875:Middle Aged; D012399:Rotation; D013704:Temporomandibular Joint / Q000502:physiology* / Q000503:physiopathology; D013705:Temporomandibular Joint Disorders / Q000175:diagnosis / Q000503:physiopathology*