Temporomandibular joint Flashcards
Temporomandibular joint aka———-. And why?
ginglymoarthroidal joint
since it is both a ginglymus (hinging joint) and an arthrodial (sliding) joint)
TMJ is a ———- type of joint of the ——- variety
an atypical synovial joint of the condylar variety
TMJ is a a joint between——— and———
temporal bone
mandible
articular surfaces of TMJ are covered by ———- and not by ———
fibrocartilage
hyaline cartilage
TMJ allows the movements of the mandible for——- and———.
speech
mastication
2 TMJ= 1——- articulation/joint.
craniomandibular
TMJ develops in——- week of intrauterine life
12th
Components of the upper articular surface of TMJ
Articular fossa, tympanic plate,articular tubercle/eminence
Components of the lower articular surface of TMJ
head of the mandible
Shape of condylar head of mandible
surface is elliptical in shape
Shape of the upper and lower articular surfaces in terms of concavity and convexity
Upper-concavo convex
Lower-concave
JOINT CAVITY Of TMJ is divided into——- and ——- compartments by an———- of fibrocartilage.
upper menisco-temporal
lower menisco-mandibular
intra-articular disc
Upper and lower section of the joint cavity of TMJ permits which mechanism of motion?
Upper: gliding
Lower: gliding and rotation
Articular Disc of TMJ is an oval plate of ——-(mainly——-, few—-)
fibrocartilage
collagen
cartilage
periphery of the articular disc of TMJ is attached firmly to the——-
fibrous capsule.
Articular disc of TMJ appears to possess a thin ——— zone and thickened———- and—— bands
intermediate
anterior
posterior
anterior band of articular disc of TMJ becomes continuous with the———-
tendon of lateral pyerygoid muscle
The posterior band splits into two laminae . What are they?…are they elastic?…and what do they attach to?
the upper elastic posterior band attaches to squamotympanic fissure(fissure in the temporal bone that runs from the temporomandibular joint to the tympanic cavity)
-lower non elastic posterior band attaches to the back of the condyle
The bilaminar region of the articular disc of TMJ contains a——-
venous plexus
INTERMEDIATE central part of the articular disc of TMJ is——-
avascular
Function of the elastic fibres in the posterior part of the disc?
elastic fibres in the posterior part of the disc bring back the disc in the articular fossa when the open mouth is closed.
Anterior relations of the TMJ
mandibular notch,mesenteric nerve and artery
Mandibular notch is also called ——-?
sigmoid notch
Posterior relations of the TMJ
tympanic plate,glenoid process of parotid gland
Lateral relations of the TMJ
parotid gland,skin
Medial relations of the TMJ
maxillary artery and vein
List the ligaments of the TMJ.
Stating which are true and which are accessory
fibrous capsule(true),temporomandibular(true),sphenomandibular(accessory),and stylomandibular(accessory) ligaments.
FIBROUS CAPSULE ligament is attached to :?
articular tubercle, squamotympanic fissure,circumference of articular fossa and neck of mandible
FIBROUS CAPSULE is loose ——-and tight——
above the articular disc
below it.
———lines the inner aspect of the capsule and neck of mandible
synovial membrane
Temporomandibular ligament aka——
lateral ligament
Temporomandibular ligament is attached above to——- and attached below to——
articular tubercle on root of zygoma
posterolateral aspect of the neck of the mandible
Temporomandibular ligament strengthens the———-
lateral aspect of the capsule
Stylomandibular ligament is attached above to the——-and attached below to the——-
lateral surface of the styloid process
angle and adjoining posterior border of the ramus of the mandible
Stylomandibular ligament is formed due to——- and seperates the——-
thickening of the investing layer of deep cervical fascia
parotid and mandibular ligament
Which ligaments control range of motion of TMJ and hold it like a swing
Accessory ligaments
Sphenomandibular ligament is attached above to the——And attached below to ——-on the—— surface of the mandible
spine of the sphenoid
lingual notch and lower margins of the mandibular foramen
medial
Sphenomandibular ligament lies on a closer plane to the joint capsule.
T/F
F. lies on a deeper plane away from the joint capsule
Sphenomandibular ligament represents the unossified part of the sheath of———
meckel’s cartilage
Sphenomandibular ligament is an important landmark when administering———
inferior alveolar nerve block
inferior alveolar nerve innervates the——- and gives a branch called the——
lower teeth
mylohyoid nerve
Sphenomandibular ligament is pierced Near its lower end by the ——?
mylohyoid nerve and vessels.
Lateral relations of Sphenomandibular ligament?
Medial relations of Sphenomandibular ligament?
Lateral: auriculotemporal nerve;lateral pterygoid,maxillary artery,inferior alveolar nerve and vessels
Medial: chordi tympani nerve,medial pterygoid , wall of pharynx
List the weird ligaments of the TMJ
- oto mandibular ligament
- disco malleolar ligament
- mallelo mandibular ligament
Disco malleolar ligament runs from - to -
neck of malleus to capsule of TMJ
Sensory nerve supply of TMJ?
Motor nerve supply of TMJ)
Sensory
- auriculotemporal nerve(post branch of mandibular nerve)
- masseteric nerve(ant branch of mandibular nerve)
Motor
Mandibular division of trigeminal nerve
blood supply to TMJ is only——- ;meaning there is no blood supply ——-capsule; the joint takes its nourishment from——-
Superficial
inside the
the synovial fluid
List the blood supply of the TMJ
maxillary artery
- superficial temporal artery
- deep auricular artery (maxillary)
- anterior tympanic artery (maxillary)
- ascending tympanic artery(maxillary)
LYMPHATIC DRAINAGE of TMJ is through ———
upper deep cervical nodes
- superficial parotid nodes(preauricular)
- deep parotid nodes
The TMJ is much more stable when the——;which is when the mandible rests on——
mouth is closed(occluded teeth)
maxilla
when teeth is occluded,the forward movement of condyle is stopped by the —-and by the contraction of ____muscle, while the backward movement of the condyle is prevented by the—— and the contraction of the—- muscle.
articular eminence
the posterior fibres of the temporalis
lateral ligament
lateral pterygoid
——-motion of the TMJ while opening the mouth occurs ———mouth opening then——motion for the rest
rotational
first for 20-25mm of
gliding
Which is a stronger action?.
Opening or closing the mouth
Closing the mouth is stronger action than the opening the mouth.
List the 5 movements of the TMJ
Depression Elevation Protraction Retraction Chewing
Gravity helps depression of the TMJ.
T/F
T
Describe the Depression movement of the TMJ
head of mandible and articular disc glide forward in the upper menisco temporal compartment
-the head also rotates forward under the articular disc
——- is the Reverse of depression of TMJ
Elevation
Describe the elevation movement of the TMJ
head of mandible and articular disc glides back in the upper menisco temporal compartment
-the head then rotates backwards under the articular disc
Describe the protraction movement of the TMJ
head of mandible and articular disc glide forward in the upper meniscotemporal compartment on both sides
Describe the retraction movement of the TMJ
head of mandible and articular disc glide backward in the upper meniscotemporal compartment
Describe the side to side chewing movements of the TMJ
occur alternately in the right and left TMJs unlike the other movements
- head of mandible and articular disc on one side glides forward
- while head of mandible of the other side just rotates on its vertical axis
In side to side chewing; the non-gliding head rotates in what axis
Vertical axis
In side to side chewing movement of the TMJ, one side of chin moves forward. What side is that?
The side that didn’t glide
Dislocation of the mandible can only occur in what direction?
dislocated only anteriorly
What Is the most unstable position of the TMJ?
When the mouth is open, the mandibular condyles move forward and lie underneath the articular eminences.
if you over yawn, and in this position there is sudden spasm of the—- muscles, ———may slip—- and get locked in the ——-preventing the mouth from closing .Passively trying to close the mouth would definitely lead to——. So instead, reduction is done by ——
lateral pterygoid
the head of the mandible of one or both sides
forward
infra temporal fossa
fracture of one or both necks of mandible
depressing the jaw with thumb placed on the last molar teeth, and simultaneously elevating the chin.
symptoms arising from TMJs and their associated masticatory muscles.
jaw pain:spasm of——
headache:spasm of——
diffuse facial pain:spasm of—-
lat. pterygoid
temporalis
masseter
Temporomandibular joint syndrome is also associated with —-in the joint that is audible when the patient is——. Caused due to the ——-of the articular disc becomes—— and the disc is trapped——
clicking and pain
chewing
posterior attachment
too stretched or detached
anteriorly
List the principal MUSCLES OF MASTICATION
PRINCIPAL temporalis Masseter Medial pterygoid Lateral pterygoid
List the accessory MUSCLES OF MASTICATION
ACCESSORY Buccinator Digastric Mylohyoid Geniohyoid
Match the following receptors to their function to the TMJ.
Rufini receptors :——
pacinian receptors :—-
golgi tendon organs:——
free nerve endings:—-
position of mandible
accelerate movement during reflexes
to protect ligaments around TMJ
pain receptors
Which muscles control the protraction and retraction of the TMJ
Protraction: medial and lateral pterygoid
Retraction: posterior fibers of temporalis ;deeper fibers of masseter; geniohyoid;digastric
Which muscles control the depression and elevation of the TMJ
Depression: lateral pterygoid, digastric, geniohyoid
Elevation: medial pterygoid, temporalis, masseter
Protrusion is mainly subserved by the ____ muscke
Lateral pterygoid
