part of part of in lateral side of connects connects develops from develops from mouth skeletal joint squamous part of temporal bone temporomandibular joint squamosal-dentary joint temporomandibular joint BTO:0003674 temporalmandibular joint UBERON:0003700 SCTID:181814009 temperomandibular joint EMAPA:19196 MESH:D013704 There are two TMJs, one on either side, working in unison. The unique feature of the TMJs is the articular disc. The disc is composed of fibrocartilagenous tissue (like the firm and flexible elastic cartilage of the ear) which is positioned between the two bones that form the joint. The TMJs are one of the only synovial joints in the human body with an articular disc, another being the sternoclavicular joint. The disc divides each joint into two. The lower joint compartment formed by the mandible and the articular disc is involved in rotational movement -- this is the initial movement of the jaw when the mouth opens. The upper joint compartment formed by the articular disk and the temporal bone is involved in translational movement -- this is the secondary gliding motion of the jaw as it is opened widely. The part of the mandible which mates to the under-surface of the disc is the condyle and the part of the temporal bone which mates to the upper surface of the disk is the glenoid (or mandibular) fossa[WP]. A synovial joint of the jaw that connects the mandible to the temporal bone. NCIT:C32888 TMJ tempero-mandibular joint FMA:54832 temporomandibular GAID:272 temporomandibular articulation Wikipedia:Temporomandibular_joint dentary-squamosal joint MA:0002899 dentary temporomandibular joint primordium joint connecting upper and lower jaws lateral structure