TMJ Flashcards
TMJ Innervation
Trigeminal (V3) mandibular division
Temporomandibular Joint
joint that allows movement of the mandible for speech and mastication. Temporal bone articulates with mandibular condyles on both sides
Temporal Bone Landmarks
Articular Eminence, Articular Fossa, Postglenoid Process
Articular Eminence
smooth, rounded ridge, anterior to Articular Fossa *subluxation/lock-jaw
Articular Fossa
oval-shaped depression, medial to zygomatic process
Postglenoid Process
sharper ridge, posterior to Articular Fossa
Joint Capsule
fibrous capsule that completely encloses TMJ
Joint Disk
between temporal bone and mandibular condyle. *divides TMJ into Upper + Lower Synovial Cavities
Synovial Fluid
secreted from membranes inside capsule. *lubricates joints, fills cavities
TMJ Ligaments
Temporomandibular, Stylomandibular, Sphenomandibular
Temporomandibular Ligament
zygomatic process to posterior condyle neck. *reinforces, prevents extension
Stylomandibular Ligament
medial surface from styloid process to angle. *becomes taut during protrusion
Sphenomandibular Ligament
spine of sphenoid to lingual of mandible. *taut during protrusion
Jaw Movements
gliding [forward + backward] | rotational [depression + evevation]
Protrusion muscle
lateral pterygoid
Retraction muscle
temporalis
Depressing the jaw requires which muscles?
Lateral pterygoid and anterior suprahyoid
Contralateral Lateral Pterygoid
*lateral deviation of mandible, occurs during mastication - one on each side L+R
Power Stroke
when teeth crunch food
Food on one side …
all opposite side closing jaw muscles contract.
Interoccusal clearance
resting position of the TMJ = 2-4mm between opposing arches.
Temporomandibular Disorder
[TMD] tenderness, swelling, pain, spasms. most symptoms originate from surrounding muscles. palpate to diagnose.
Subluxation
dislocation of both joints; *head of condyles moves too far anterior on articular eminence.
Trismus
inability to normally open the mouth; symptom of TMD + subluxation
