Comparative study of plastination section of the human temporomandibular joint in the position of mandibular lateral displacement and edge-to-edge of dental occlusion / 实用口腔医学杂志

ABSTRACT

Objective:To analyse the anatomical change of the human temporomandibular joint(TMJ) in the position of mandibular lateral displacement and to provide the anatomical data for temporomandibular disorder.Methods:3 of the 8 samples of selected fresh cadavers were adjusted to mandibular lateral displacement position, and 5 to edge-to-edge occlusion position,then samples were fixed and sectioned according to coronal and sagittal planes by using plastination technique. The feature of the thin plastination sections of the TMJ in the mandibular lateral displacement position and were compared with that in edge-to-edge occlusion position.Results:On the working side in mandibular lateral displacement position, condylar moved backwords,upwards and outside in the articular fossa. Articular discs of TMJ did not move following condylar movement,but posterior band of the articular disc was suppressed by the condylar and articular fossa. On the non-working side in mandibular lateral displacement position, condylar moved ahead,downwards and inwards along posterior incline of articular tuberculum,then articular discs did not move,and middle band of articular discs was suppressed by the condyle and articular tuberculum.Conclusions:The TMJ disc does not shift as TMJ condylar process turns in articular fossa.When the condylar turns and slides at the same time,the articular discs shift.