BSC 1085C Lecture Notes - Lecture 13: Masseter Muscle, Sphenoid Bone, Temporal Bone
Document Summary
Temporomandibular joint (tmj): the tmj allows 5 main motions and they are, mandibular depression, mandibular elevation, mandibular lateral deviation-in either side, mandibular protrusion (protraction, mandibular retrusion (retraction) The tmj allows for the mouth to open so that it accepts 2-3 fingers to fit within the opening. Bony landmarks of the structures surrounding the tmj: the mandible, the temporal bone, the zygomatic arch, understand the upper jaw and the lower jaw; both divided by the articular disc found within the tmj. Other bony landmarks worthy of exploring: the styloid process, the mastoid process, the maxilla, the external auditory meatus, the sphenoid bone, the hyoid bone and the thyroid cartilage. Pterygoids = responsible for opening the jaw; mylohyoid muscle = elevates the hyoid bone and the tongue; Geniohyoid = move the hyoid bone up and forward during mastication; stylohyoid = brings the hyoid bone backwards and elevates the tongue.
