Ob Lecture 11A Part 2

Front 1

point of insertion of bundles into cement?

do all sharpeys insert into bone?

Back 1

sharpeys fibers

no they wrap around blood vessels

Front 2

what is an oxytalan fiber?

Back 2

attach to cement and branch out into PL

seems to get thicker in periods of high load >>ORTHO DONTICS

stain for fibronectin so may be impt for fibrobalst adhesion

Front 3

what lies in iS space of PL?

Back 3

blood vessels, nerves, lymphocytes (MLG macroph, lymphocytes, granulocytes)

Front 4

where does blood to PL come from? what does blood do for PL?

Back 4

BVs from bone, and root...

blood nourishes cell, helps for repair, allows PL to modify and repair itself during tooth movement and mastication

Front 5

what is particular about the capillaries in PL?

Back 5

they are fenstrated...have pores! allows for exchange of material more quickly

Front 6

what does lymph do?

what do capillaries bring in? take away?

Back 6

picks up excess fluid that has leaked out of circ, filters it through lymph nodes and returns it to circulation

bring o2 and nutrients, take away C02 and waste.

Front 7

what kind of nerves in PL?

what are the two types of motor nerves?

Back 7

1) SENSORY- pressure and pain nerves- from sn to cns

2) autonomic- smooth muscle, and BV

voluntary- from CNS to the part of body

Front 8

what innervates the blood vessels of pl

Back 8

Autonomic motor nerves- contraction and relaxation

Front 9

most common CELLl in PL?

Back 9

fibroblast.

impt for producing collagen, also acts as A FIBROCLAST when it breaks down aged collagen

Front 10

what does a fibroblast look like under a microscope?

Back 10

large and NUCLEUS with hertero and euchromatin, Rer.

simple desmosomes, gap junctions. CILIUM FOR sensory function and it has receptors

Front 11

theories of orientation for collagen?

Back 11

internal- orientation of fibroblast controls bundle direction

outside- external force determines direction

collagen bundles are piezoelectric- when subject to force they become polarized and this can effect bundle orientation

Front 12

what may epithelial rests do in the mature tooth?

Back 12

inhibiting and stimulating cement formation

Front 13

what is ground substance made of?

Back 13

water, proteoglycans, GAG, glycoproteins

Front 14

outside theory- PG?

Back 14

glycosaminoglycans (ps units) that covalently bind to protein and hyaluronic acid (forms proteoglycans) may bind water and influence orientation

Front 15

aging of PL

Back 15

cement and bone become scalloped, less PL attachment as a result

Front 16

Alveolar bone, what does it form?

Back 16

socket for the tooth to sit in

Front 17

Alveolar make up...weight %s?

Back 17

60% inorg, 25% org, 15% water

Inorg. is hydroxyapatie, organic is 90% collagen (T1 and 3)

200 other proteins

Front 18

Outer area of ab called? inner area?
big space b/w 2 lumps? fist part before little space? little space b/w 2 lumps?

Back 18

outer alveolar plate, inner alveolar plate

big space b/w 2 lumps interdental septum

top of first lump cribriform plate lining the socket (lamina dura, or bundle bone

inb/w 2 lumps interradicular septum

Front 19

surface of AB, compact or spongy?

Back 19

compact bone- has osteocytes living in lacunae, have canaliculi. Arranged in lamellae at the surface. Haversian canalas supply blood and nerve!

Front 20

how are nutrients passed in the compact bone?

Back 20

Diffuse from the haversion canals to the cells using canaliculi

Front 21

Deepest part of alveolar bone is what kind of bone?

Back 21

spongy bone/ trabecular bone.

Front 22

prematerial secreted by cementoblast? osteoblast?

Back 22

cementoid, osteoid --> both then mineralized

Front 23

where are osteoblasts, how do they arrange themselves?

Back 23

osteoblasts are on the surface of the bone, form an epithelium with tight jxns

Front 24

mature bone cell? ways of communicating? cell structure?

Back 24

osteocytes in lacuane, communicate with tight jxns and canaliculi.

few organelles, have cell processes that stretch down the canaliculi

Front 25

osteoclasts? appearance? what do they leave areas looking like?

Back 25

large multinucleate cells which digest bone, ruffles cell membrane.
demineralize areas and leave behind bare collagen

Front 26

Teeth are always moving during what...what does this do?

What else causes bones in head to change?


what does pressure do (think squishing bone)
tension? (pulling so have to make new stuff)

Back 26

move during eruption...causes PL, ab, and cement to be constantly remodelling

growth of head, anterior and lateral shifting of teeth.

orthodontists create force and tension to cause bone reformations

pressure= birth on bone is resorption

tension = new bone