TEMPOROMANDIBULAR-JOINT MOBILITY ASSESSMENT - A COMPARISON BETWEEN 4 METHODS

Temporomandibular joint (TMJ) mobility is assessed in different ways. Measurement of the interincisal distance in maximal mouth opening adde d to the vertical overlap of the dentition, i.e. linear mouth opening (LMO); measurement of angular displacement of the mandible relative to the cranium at maximal mouth opening, i.e. angle of mouth opening (AM O); assessment of the condylar position relative to the articular emin ence performed on transpharyngeal radiographs in maximal mouth opening , i.e. condylar mobility (CM); measurement of angular displacement of the mandible at maximal mouth opening relative to the closed mouth pos ition of the mandible, assessed on transpharyngeal radiographs in maxi mally opened and in closed mouth position, i.e. radiographic angle of mouth opening (RAMO). To compare these TMJ mobility assessment methods and to analyse the relationship between LMO, AMO and mandibular lengt h (ML), 28 healthy volunteers (13 females, 15 males), mean age 29.6 ye ars (range 21-41) with a symmetrical mouth opening pattern were assess ed. LMO, AMO, ML, and RAMO were measured and CM was assessed on transp haryngeal radiographs. LMO and AMO were strongly and significantly rel ated (r=0.71). LMO was significantly influenced by AMO and ML. No sign ificant differences between AMO and RAMO were found. CM was strongly a nd significantly related to AMO (r=0.72) and weakly but significantly related to LMO (r=0.42). Based on the results of this study recommenda tions are made regarding the appropriate application of TMJ mobility a ssessment methods.