Temporomandibular Joint Flashcards
The Temporo-Mandibular Joint consists of _____ bone suspended from the _____ bone via ______ and ______
Mandible
Temporal
Ligaments and muscles
TMJ is a true synovial joint.
True/False
Why?
True
It is a true synovial joint because it is able to perform movements such as gliding, hinging, sliding and slight rotation
Both bones that make up TMJ are separated by a _______ which divides it into ______cavities
Meniscus disc
Two
TMJ is made of _______ of mandible articulating with _______ of temporal bone.
Condyloid process
Mandibular Fossa
At the TMJ _______ surrounds the articular surfaces and blends with ______.
Fibrous capsules
Articulate disc
TMJ is lined by __________ except the _____________
Synovial membrane
Articular disc surface
TMJ has _______ strengthening its joints.
Ligaments
The ligaments of the TMJ are:
(hint: three answers with their positions)
temporomandibular – lateral
sphenomandibular - anterior
stylomandibular - posterior
The maxillary vessel lies between the ______ ligament and the _____
Sphenomandibular
Neck of condyle
Stylomandibular ligament separates the
_______ gland from the ______ gland
Submandibular
Parotid
External carotid artery divides into terminal branches behind the ____
Neck
___________ lies between the sphenomandibular ligament and neck of condyle.
Maxillary vessel
____________ ligament separates the submandibular gland from the parotid gland
Stylomandibular
__________ divides into terminal branches behind the neck.
External Carotid artery
__________ enters the mandibular foramen
Inferior Alveolar Nerve
______ nerve runs parallel, medial and posterior to the inferior alveolar nerve
Lingual
Lingual nerve runs _____ , ______ , ______ to the inferior alveolar nerve
Parallel
Medial
Posterior
Anterior boundary of TMJ
anterior joint eminence
(Lateral pterygoid muscle , masseteric nerve and vessels)
Posterior boundary of TMJ:
external auditory meatus
(glenoid process of parotid gland)
Lateral boundary of TMJ:
zygomatic arch
(parotid gland, fascia and skin)
Medial boundary of TMJ:
styloid process
(maxillary vessels and auriculotemporal nerve)
List all the muscles of mastication:
Temporalis
Masseter
Medial Pterygoid
Lateral Pterygoid
Suprahyoid and Infrahyoid
Anterior part of Temporalis _____
Closes the jaw
Posterior part of temporalis _____
Retracts the jaw
Masseter muscle performs what action:
Closes the jaw
Medial Pterygoid muscle performs what action?
Closes the jaw
Lateral Pterygoid muscle performs what actions:
depresses, protudes and moves the mandible from side to side
Suprahyoid and Infrahyoid muscle performs what action:
Depression of mandible
All the muscles of mastication are innervated by:
Mandibular division of trigeminal nerve
What is protraction?
What muscles perform protractions?
It is the forward movement of the mouth
Lateral Pterygoid
Medial pterygoid
Superior fibres of masseter
What is retraction?
What muscles perform retraction?
It is the backward movement of the mouth
Temporalis
Deep fibers of masseter
Digastric
Geniohyoid
Protraction and Retraction occurs in the _____
Superior compartment
Elevation is produced by:
Temporalis
Masseter
Medial pterygoid
Depression is produced by;
Gravity,
Lateral pterygoid,
Digastric,
Geniohyoid,
Mylohyoid
Lateral rotation is produced by:
Medial Pterygoid
Lateral Pterygoid
Meniscus disc is held in place by ______ and ______ and _____
Medial Capsular ligament
Lateral capsular ligament
Retro-disc pad
Synovial fluid can be found only above the meniscus disc.
True/False
False; synovial fluid can be found above and below the meniscus disc.
Blood and Nerve Supply of TMJ:
Superficial temporal – terminal branch external carotid artery
•Maxillary artery – from external carotid artery
•Inferior alveolar nerve – mylohyoid and lingular
•Middle meningeal
•Auriculotemporal nerve - from the posterior division of mandibular branch
•Masseteric nerve - from anterior division of the mandibular branch trigeminal of
Clinical considerations of TMJ:
Dislocation of the jaw anteriorly resulting from blow against the jaw when opened
•Injury to the external auditory meatus
•Crepitus of TMJ arises from delayed movement of the articular disc
•Branching of facial nerve and auriculo- temporal nerve arising near the joint
•Arthritis of the joint – inflammatory changes causing pains and functional deficit
•Locking of jaw in tetanus and paralyses of
