Temporomandibular Joint

Question 1

The Temporo-Mandibular Joint consists of _____ bone suspended from the _____ bone via ______ and ______

Answer 1

Mandible
Temporal
Ligaments and muscles

Question 2

TMJ is a true synovial joint.
True/False
Why?

Answer 2

True
It is a true synovial joint because it is able to perform movements such as gliding, hinging, sliding and slight rotation

Question 3

Both bones that make up TMJ are separated by a _______ which divides it into ______cavities

Answer 3

Meniscus disc
Two

Question 4

TMJ is made of _______ of mandible articulating with _______ of temporal bone.

Answer 4

Condyloid process
Mandibular Fossa

Question 5

At the TMJ _______ surrounds the articular surfaces and blends with ______.

Answer 5

Fibrous capsules
Articulate disc

Question 6

TMJ is lined by __________ except the _____________

Answer 6

Synovial membrane
Articular disc surface

Question 7

TMJ has _______ strengthening its joints.

Answer 7

Ligaments

Question 8

The ligaments of the TMJ are:
(hint: three answers with their positions)

Answer 8

temporomandibular – lateral
sphenomandibular - anterior
stylomandibular - posterior

Question 9

The maxillary vessel lies between the ______ ligament and the _____

Answer 9

Sphenomandibular
Neck of condyle

Question 10

Stylomandibular ligament separates the
_______ gland from the ______ gland

Answer 10

Submandibular
Parotid

Question 11

External carotid artery divides into terminal branches behind the ____

Answer 11

Neck

Question 12

___________ lies between the sphenomandibular ligament and neck of condyle.

Answer 12

Maxillary vessel

Question 13

____________ ligament separates the submandibular gland from the parotid gland

Answer 13

Stylomandibular

Question 14

__________ divides into terminal branches behind the neck.

Answer 14

External Carotid artery

Question 15

__________ enters the mandibular foramen

Answer 15

Inferior Alveolar Nerve

Question 16

______ nerve runs parallel, medial and posterior to the inferior alveolar nerve

Answer 16

Lingual

Question 17

Lingual nerve runs _____ , ______ , ______ to the inferior alveolar nerve

Answer 17

Parallel
Medial
Posterior

Question 18

Anterior boundary of TMJ

Answer 18

anterior joint eminence
(Lateral pterygoid muscle , masseteric nerve and vessels)

Question 19

Posterior boundary of TMJ:

Answer 19

external auditory meatus
(glenoid process of parotid gland)

Question 20

Lateral boundary of TMJ:

Answer 20

zygomatic arch
(parotid gland, fascia and skin)

Question 21

Medial boundary of TMJ:

Answer 21

styloid process
(maxillary vessels and auriculotemporal nerve)

Question 22

List all the muscles of mastication:

Answer 22

Temporalis
Masseter
Medial Pterygoid
Lateral Pterygoid
Suprahyoid and Infrahyoid

Question 23

Anterior part of Temporalis _____

Answer 23

Closes the jaw

Question 24

Posterior part of temporalis _____

Answer 24

Retracts the jaw

Question 25

Masseter muscle performs what action:

Answer 25

Closes the jaw

Question 26

Medial Pterygoid muscle performs what action?

Answer 26

Closes the jaw

Question 27

Lateral Pterygoid muscle performs what actions:

Answer 27

depresses, protudes and moves the mandible from side to side

Question 28

Suprahyoid and Infrahyoid muscle performs what action:

Answer 28

Depression of mandible

Question 29

All the muscles of mastication are innervated by:

Answer 29

Mandibular division of trigeminal nerve

Question 30

What is protraction? What muscles perform protractions?

Answer 30

It is the forward movement of the mouth Lateral Pterygoid Medial pterygoid Superior fibres of masseter

Question 31

What is retraction? What muscles perform retraction?

Answer 31

It is the backward movement of the mouth Temporalis Deep fibers of masseter Digastric Geniohyoid

Question 32

Protraction and Retraction occurs in the _____

Answer 32

Superior compartment

Question 33

Elevation is produced by:

Answer 33

Temporalis Masseter Medial pterygoid

Question 34

Depression is produced by;

Answer 34

Gravity, Lateral pterygoid, Digastric, Geniohyoid, Mylohyoid

Question 35

Lateral rotation is produced by:

Answer 35

Medial Pterygoid Lateral Pterygoid

Question 36

Meniscus disc is held in place by ______ and ______ and _____

Answer 36

Medial Capsular ligament Lateral capsular ligament Retro-disc pad

Question 37

Synovial fluid can be found only above the meniscus disc. True/False

Answer 37

False; synovial fluid can be found above and below the meniscus disc.

Question 38

Blood and Nerve Supply of TMJ:

Answer 38

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

Question 39

Clinical considerations of TMJ:

Answer 39

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