Mandibular kinematics in patients with alloplastic total temporomandibular joint replacement--a prospective study.
OBJECTIVE
The purpose was to analyze the mandibular patterns (condylar range of motion during opening; incisal range of motion during opening, lateral excursion, and protrusion; velocity during opening and closing; mandibular rotation angle during opening and closing) in patients with alloplastic total joint replacement (TJR).


METHODS
Seventeen patients with different diagnoses resulting in condylar hypomobility (8 patients, 15 joints) and condylar instability (9 patients, 12 joints) had undergone alloplastic TJR. Data were recorded preoperatively and 2, 6, and at least 12 months postoperatively. For ordinal data comparison at different time points, the Wilcoxon signed-ranks test was used.


RESULTS
Analysis of the kinematic data at least 12 months postoperatively showed in patients with condylar hypomobility a statistically significant increase in all measured data except the incisal range of motion lateral excursion. In patients with condylar instability, the results showed a statistically significant decrease for incisal range of motion protrusion and laterotrusion. A slight increase in condylar range of motion, incisal range of motion linear distance, and velocity during opening and closing was found.


CONCLUSIONS
Even after successful alloplastic TJR, a complete restoration of normal joint function is not achievable. Nevertheless, the kinematic data indicate that alloplastic TJR results in an improved function in patients with joint hypomobility and in a decrease of abnormal hypermobility in patients with condylar instability.
Department of Prosthodontics, Preclinical Education, and Dental Materials Science, University Hospital Bonn, Bonn, Germany. sabinelinsen@web.de
Sabine S
SS
Linsen
Rudolf H
RH
Reich
Marcus
M
Teschke
D000328:Adult; D000368:Aged; D000844:Ankylosis / Q000601:surgery; D001168:Arthritis / Q000601:surgery; D019643:Arthroplasty, Replacement / Q000295:instrumentation*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D021621:Imaging, Three-Dimensional / Q000295:instrumentation; D007593:Joint Instability / Q000601:surgery; D007595:Joint Prosthesis; D008297:Male; D008334:Mandible / Q000503:physiopathology; D008335:Mandibular Condyle / Q000503:physiopathology* / Q000601:surgery; D008875:Middle Aged; D009068:Movement; D011446:Prospective Studies; D011474:Prosthesis Design; D016059:Range of Motion, Articular / Q000502:physiology*; D012399:Rotation; D013704:Temporomandibular Joint / Q000503:physiopathology / Q000601:surgery*; D013705:Temporomandibular Joint Disorders / Q000601:surgery; D016896:Treatment Outcome; D014465:Ultrasonics / Q000295:instrumentation; D055815:Young Adult