Temperomandibular Joint Flashcards
What type of joints form the temporomandibular joint?
Plane and hinge synovial joints
What are the 2 superior articulations of the temporomandibular joint?
- Mandibular fossa of temporal bone
2. Zygomatic process of temporal bone
What is the inferior articulation of the temporomandibular joint?
Condylar process of mandible
What covers the articular surfaces of the temporomandibular joint?
Fibrocartilage
What is the superior attachment of the fibrous capsule found in the temporomandibular joint?
Area surrounding mandibular fossa and articular tubercle of temporal fossa
What is the inferior attachment of the fibrous capsule found in the temporomandibular joint?
Periphery of the condylar neck
What is the nerve supply of the fibrous capsule found in the temporomandibular joint??
- Auriculotemporal branch of mandibular nerve
2. Masseteric branch of mandibular nerve
What is the arterial supply of the fibrous capsule found in the temporomandibular joint?
Superficial temporal artery
What is the venous drainage of the fibrous capsule found in the temporomandibular joint?
Retromandibular vein
What ligament reinforces fibrous capsule surrounding the temporomandibular joint?
Lateral temporomandibular ligament
What are the 2 accessory ligaments of the temporomandibular joint?
- Stylomandibular ligament
2. Sphenomandibular ligament
Where is the lateral temporomandibular ligament attached?
Articular tubercle and neck of mandible
What is the function of the lateral temporomandibular ligament?
Prevents posterior and inferior displacement of the condyle
Where is the stylomandibular ligament attached?
Styloid process of temporal bone to angle of mandible
Where is the sphenomandibular ligament attached?
Spine of sphenoid and lingula of mandible
What movements does the lower part of the temporomandibular joint account for?
Hinge-like depression of elevation of head of the mandible
What movements does the upper part of the temporomandibular joint account for?
Protrusion onto articular tubercle or retraction into mandibular fossa
What 2 movements of the mandible causes the mouth to open?
- Depression
2. Protrusion
How does the temporomandibular joint cause protrusion of the mandible?
Mandible and disc slide forward by lateral pterygoid assisted by medial pterygoid
How does the temporomandibular joint cause retraction of the mandible?
Mandible and disc move posteriorly by posterior fibres of temporalis
How does depression of mandible occur?
Gravity and suprahyoid
What 3 muscles cause elevation of the mandible?
- Masseter
- Medial pterygoid
- Temporalis
What is the bilateral action of the pterygoid muscles?
Side to side movement of the mandible
How does an anterior dislocation of the mandible occur?
Head of mandible has been forced anteriorly so no longer articulates with mandibular fossa of temporal bone
What is the way to reduce a dislocated jaw?
Pushing downwards on lower molar teeth and jaw backwards
What is the function of downward pressure during the reduction of a dislocated jaw?
Overcomes tension of temporalis and masseter
What is the function of backwards pressure during the reduction of the dislocated jaw?
Overcome spasm of lateral pterygoid
What are the two terminal branches of the external carotid?
- Superficial temporal
2. Maxillary artery
Where does the external carotid artery terminate?
Level of neck of the mandible
What is the course of the maxillary artery once it arises from the external carotid?
- Passes over lateral pterygoid muscle
2. Disappears in the pterygopalatine fossa
What divides the maxillary artery into 3 parts?
Lateral pterygoid muscle
What is the venous drainage of the area supplied by the maxillary artery?
Pterygoid plexus of veins
Where is the pterygoid plexus of veins found?
Lies between medial and lateral pterygoid
What drains the pterygoid venous plexus?
Maxillary vein
What are the 2 main communications of the pterygoid venous plexus?
- Cavernous sinus
2. Facial vein
What connects the pterygoid venous plexus and cavernous sinus?
Emissary veins
What connects the pterygoid venous plexus and facial vein?
Deep facial vein