Oral histology EXAM 2

articular zone

identify A

proliferative zone

identify B

fibrocartilaginous zone

identify C

calcified cartilage

identify D

capsule

surrounds joint, attaches to neck of condyle and temp bone

synovial membrane

lines inner part of capsule (not disc and articular surface)

articular disc

fibrocartilaginous structure continuous with capsule that separates the joint cavity and improves fit of bones.

superior joint cavity

what is 4

inferior lamina

what is 5

superior lamina

identify 6

inferior joint cavity

identify 7

lateral pterygoid

what is 8

retrodiscal pad

identify 9

free, ruffini’s, pacini’s, golgi

four types of nerve endings in TMJ

free nerve ending

what is the major type of nerve ending in the TMJ

free nerve ending

nociceptor (pain) in the TMJ

ruffini’s corpuscle

nerve ending in TMJ functioning in dynamic PROPRIOception

pacini’s corpuscle

nerve ending in TMJ functioning in dynamic MECHNOreception

golgi tendon organ

proprioceptor near MYOTENDINOUS junction that senses changes in MUSCLE TENSION

fibrocartilage

what is the TMJ disc made of

fibrochondrocytes

cells found in TMJ disc that produce and maintain fibrous and cartilaginous matrix.

fibrous connective tissue (type 1 collagen) and GAGs

components of TMJ disc extracellular matrix

avascular and lacks innervation

Characterizes the TMJ disc which affects its healing capacity

where disc meets capsule

where is the nerve and blood supply of the TMJ

mediolateral

direction of fiber in ANTERIOR and POSTERIOR bands

anteroposterior

direction of fiber in INTERMEDIATE band

articular disc

identify 1

horizontal ligament

identify 2

oblique ligament

identify 3

auriculotemporal, masseteric, deep temporal (all CN V3)

what nerves innervate the TMJ

AP direction of collagen fibers

why is the TMJ disc stronger in AP direction

forms primitive jaw (malleus)

what happens to the meckel’s cartilage

intramembranous

what type of ossification forms the mandible

condensation stage

stage of TMJ formation where mesenchyme forms condylar blastema that grows towards temporal blastema

temporal blastema

what is A

condylar blastema

what is B

cavitation stage

stage of TMJ formation where clefts form in the condylar and temporal blastema, leading to the development of joint spaces.

inferior joint cavity

forms from cleft ABOVE condylar blastema

superior joint cavity

forms from cleft BELOW temporal blastema

TMJ disc

what does the tissue between the two clefts in the cavitation stage form?

cavitation stage

when does the condylar blastema become cartilage

condensation

what stage is this?

cavitation

what stage is this?

maturation stage

what stage is this?

maturation stage

stage of TMJ formation where tissues attain mature morphology

temporal condensation

forms in optic capsule of cranial base

fibrous tissue

what covers the joint surface of the TMJ?

multidirectional

what is the directional growth potential of the TMJ

mandibular condyle

major site of mandibular growth

long bone (unidirectional growth)

where can this type of bone be found?

cartilage decreases in thickness

what happens to the condylar surface as we age?

condyle (multidirectional growth)

where can this type of bone be found

colateral ligaments

what binds the disc to the condyle

rotation

what type of movement occurs between the DISC and the CONDYLE (inferior cavity)

sliding/translation

what type of rotation occurs between the DISC and MANDIBULAR FOSSA

posterior

which way does the disc move during opening ROTATION

passive opening

what position is this TMJ in

anterior disc displacement

what is the ISSUE indicatacted by the arrow

temporal blastema

where does structure A come from

fibrocartilage

what is the fibrous material on the surface of the TMJ

meckels cartilage, articular cartilage, condylar condensation, condylar cartilage

what is the series of cartilage formation for condylar cartilage

meckels cartilage

stimulates condylar condensation

condylar cartilage

which secondary cartilage is incorporated into the mandible

A

which direction (A or B) is anterior

down and anterior

which DIRECTION will the mandibular CONDYLE move as the jaw OPENS

down and anterior

which DIRECTION will articular DISC move as the jaw OPENS

clicking

what happens if the disc moves more than condyle during opening

type I collagen

helps disc resist tensile loading

nothing, forms primitive jaw

what does meckels cartilage contribute to OSSEOUS development of TMJ

posterior temporalis and deep masseter

which muscles RETRACT/RETRUDE the condyle during jaw closing

motor end plate

Each muscle FIBER has ONLY ONE of these neuromuscular junctions that transmit signals from motor neurons to muscle fibers.

auriculotemporal

provides SENSORY information from area of mandibular condyle

large variety of motor tasks

why are muscles of mastication so different from skeletal muscles

PDL

collagen fibers. between TOOTH ROOT and ALVEOLAR bone

sharpey’s fibers

PDL collagen fibers embedded in ROOT CEMENTUM and ALVEOLAR BONE

coronal 2/3

where does ACELLULAR cementum occur

apical 1/3

where does CELLULAR cementum occur

cementum(cementoblasts), PDL (fibroblasts), and alveolar bone (osteoblasts)

what does the dental follicle gives rise to

oblique

how would you categorize thee PDL fiber indicated by the double headed arrow?

acellular

what kind of cementum would be in the area indicated

cribriform plate/alveolar bone proper

what bone is indicated by the arrows

acellular afibrillar

which kind of cementum forms at the CEJ

A (overlap)

which of these conditions is the most common form of acellular afribrillar cementum

acellular cementum

which cementum occurs FIRST (primary)

reduced enamel epithelium

forms junctional epithelium

acellular afibrillar

what type of cementum is here

cellular

which cementum forms in POST-FUNCTIONAL stage of tooth eruption

cellular cementum

thicker cementum with CEMENTOCYTES embedded

acellular

which cementum has mostly EXTRINSIC FIBERS

cellular

which cementum has mostly INTRINSIC FIBERS

acellular (primary)

which cementum functions in ATTACHMENT

cellular

which cementum functions in MAITAINING TOOTH POSITION

anterior displacement with reduction

disc displaced and RETURNS to normal position when jaw opens

anterior displacement without reduction

disc is displaced and STAYS displaced

lateral pterygoid

muscle that functions in PROTRUSION

masseter, temporalis, medial pterygoid

muscles that function in ELEVATION/CLOSING

suprahyoid, infrahyoid, lateral pterygoid

muscles that function in DEPRESSION/OPENING

muscle fascicle

individually wrapped in PERIMYSIUM, vessels and nerves travel in between

muscle fiber

long thin multinucleated post-mitotic cells individually wrapped in ENDOMYSIUM

sarcomere

contractile unit of muscle