Session 3 - TMJ Flashcards
What three muscles are found in the infratemporal fossa?
Inferior part of temporalis
Medial and lateral ptergoid
What three arteries are found in the infratemporal fossa?
Maxillary artery
Middle meningeal artery
Superficial temporal artery
What three veins are found in the infratemporal fossa?
Maxillary vein
Middle meningeal vein
Pterygoid venous plexus
What 7 nerves are found in the infratemporal fossa?
Mandibular nerve Auriculotemporal nerve Inferior alveolar nerve Lingual nerve Buccal nerve Chorda tympani Otic ganglion
Give five openings that are found in the infratemporal fossa?
Foramen ovale Foramen spinosum Alveolar canal Inferior orbital fissure Pterygomaxillary fissure
Outline a mandibular nerve block
Anaesthetic injected near foramen ovale to block mandibular nerve
Name four nerves which are also affected in mandibular nerve block
Inferior alveolar
Lingual
Buccal
Auriculotemporal
Outline an inferior alveolar nerve block
Anaesthetic injected around mandibular foramen, from which the inferior alveolar nerve and vessels protrude
What is aneasthatised in a inferior alveolar nerve block?
All mandibular teeth are aneathetised on medial side Skin and mucous membrane of lower lip Labial alveolar mucosa Gingivae Skin
Why do you often lose sensation in the anterior 2/3 of your tongue during an inferior alveolar nerve block?
Lingual nerve often involved
What type of joint is the temporomandibular joint?
Modified hinge type synovial join between mandible and cranium
What are the two superior articular surfaces of the TMJ?
Mandibular fossa
Articular tubercle
What is the inferior articular surface of the TMJ?
Head of the mandible
What cushions the TMJ?
The articular disc, a fibrocartilage structure, which creates two separate compartments - the superior and inferior articular cavities
What are the two main movement types of the TMJ?
Gliding (superior joint cavity used)
Hinge (inferior joint cavity)
What muscles are involved in flexion of the TMJ, and what compartment does this movement occur
Temporalis, masseter, medial pterygoid
Inferior
What muscles are involved in extension of the TMJ, and what compartment does this movement occur
Lateral pterygoid, suprahyoid, infrahyoid
Inferior
What muscles are involved in gliding of the TMJ, and what compartment does this movement occur
Protrusion - Lateral pterygoid, medial ptergoid, masseter
Retrusion - Temporalis, masseter
Superior compartment
In what compartment does rotation of the TMJ occur?
Inferior
Name the ligaments of the TMJ
Temporomandibular ligament (x1) - Deep fibres blend with joint capsule Sphenomandibular ligament (x2) Stylomandibular ligament
When is the TMJ most stable?
Mandibular condyle is in contact with the mandibular fossa
Teeth in occlussal contact
How does dislocation of the TMJ occur?
Sometimes during yawning or taking a large bite. Sideways blow to chin when mouth open.
Excessive contraction of the lateral pterygoids to dislocate anteriorly
Mouth remains depressed
What is bruxism?
Grinding teeth when asleep
What is TPDD?
Temporomandibular Pain Dysfunction Disorders
Muscular pain
What is a mal-occlusion syndrome?
Muscular pain?
