Alveolar Bone

Question 1

Periodontium

Answer 1

tissues around tooth used for structural attachment and maintenance

Question 2

Periodontal disease

Answer 2

chronic gingival inflammation with varied periodontal attachment loss
- Plaque induced
- Host mediated - increases immune response + failure to turn off inflame
- Env modified - e.g. smoking, diabetes,
- Site -specific - not all teeth destroyed the same and not all parts of tooth have equal disease
(SHE P)

Question 3

Bone

Answer 3

Cortical and cancellous bone

Has osteons

Question 4

Cell types in BONE

Answer 4

1. Osteoblast: alkaline phosphatase, Collage 1, 3, 5 MMPs
2. OsteoCLAST: acid phosphatase, H+ pump, TRAP
3. Osteocyte
4. Pluripotent SC

Question 5

Cementum

Answer 5

Acellular and cellular cementum
NO osteons
Cell: cementoblast
Collagen I, 3, 5, alkaline phosphatase

Question 6

PDL

Answer 6

Type 1 collagen fibers
Fibroblast : Collagen 1, 3, 5 fibronectin, lysyl oxidase
Pluripotent SC

Question 7

Components of Periodontium

Answer 7

Alveolar bone, PDL, Cementum, Gingiva

Question 8

Gingiva

Answer 8

two parts: Corium and Epithelium

Corium : type I collagen fibers, fibroblast, Collagen I, 3, 5 fibronectin lysyl oxidase

Question 9

Gingiva E

Answer 9

Epithelium:
stratified squamous epithelium, membrane coating keratohyaline granules
Cell: keratinocyte
BM: Type 4 collagen, integrin, laminin
Cell-cell adhesions: cadherin, CAMs, keratin
Keratinized outer layer: flaggrin/loricrin, keratin

Question 10

Alveolar crest

Answer 10

coronal junction of outer/inner cortical plates

• Crestal, supporting bone, crystal lamina dura
• Healthy=1-2 mm apical from CEJ

Question 11

Inner cortical plate

Answer 11

• Bundle - attachment for PDL fiber bundles
• Supporting Bone
• Cribriform plate - perforated by foramina for neurovasculature structures to pass
• Alveolar Bone Proper
• Lamina Dura - “dense layer” derived from dental follicle/sac
  BS CAL

Question 12

Outer Cortical Plate

Answer 12

• Cortical
• Lamellar
• Compact
• Non-supporting bone

Question 13

Marrow Bone

Answer 13

• Cancellous, trabeclar, spongy, medullary, non-supporting, central sponges?

Question 14

Alveolar bone

Answer 14

Formed by INTRAMEMBRANOUS mechanism

• thickened ridge of bone circumscribing and forming tooth sockets
• well vascularized, highly inn/mineralized
• Type I collagen fibers

Question 15

Alveolar Bone FXNS

Answer 15

1. Attachment/support
2. Protection
3. Mineral reservoir
   Supplied by: superior and inferior alveolar artieres + Haversian system, CN-V

Question 16

Endochondral bone formation

Answer 16

cartilage skeleton

LONG bones

Question 17

Intramembranous bone formation

Answer 17

No cartilaginous precursor
FLAT bones (skull)
bone directly from MESENCHYME

Question 18

Sutural bone growth

Answer 18

form of intramembraneous bone formation

fusion of flat bone sutures (skull)

Question 19

Bone Turnover

Answer 19

Replacement of old with ne, rate of turnover slows with inc age

1. Formation/resorption coupled
2. Regulated via hormones (PTH, VitD, calcitonin, estrogen), GFs, cytokines, prostaglandins

Question 20

Turnover, CUTTING CONE

Answer 20

leading edge of reposition
occurs in migrating groups
residual osteons become interstitial lamellae

Question 21

FILLING CONE, turnover

Answer 21

active formation area

- bone formation also occurs in migrating groups

Question 22

Reversal lines

Answer 22

formation of new bone against old bone - staining pattern of adhesive phosphoproteins
- occurs b/c of H&E stain. Scalloped interface (seam) between old bone and new matrix

Question 23

Bone formation

Answer 23

1. Course fibered woven bone - embryonic bone
2. Immature bone - neonatal
3. Lamellar - adult

Question 24

Lamellar bone

Answer 24

Outside of bone
Dense
Well organized osteons
Thicker when more force/stress
Cortical, compact, dense, periosteum-associated

Question 25

Cancellous bone

Answer 25

network of trabecular (thin spicules of bone tissue)
Interior of lamellar bone
“spongy, trabecular, marrow, medullary, endosteum-associated”

Question 26

Marrow spaces

Answer 26

soft/spongy bone within central medullary cavity
RED MARROw -> vascular, RBCs
Yellow marrow - fatty

Question 27

Interstitial Lamella (1/3)

Answer 27

1. Interstitial lamella - gaps between osteons made of resorbed osteons
   - fill in spaces between adj concentric lamellae; residual fragments of pre-exiting concentric lamellae that have undergone remodeling

Question 28

Concentric Lamella (2/3)

Answer 28

Osteons; bulk of bone

THICK, vascular

Question 29

Outer circumferential lamellae (3/3)

Answer 29

Below periosteum
THIN, AVASCULAR
outer perimeter that encloses bone

Question 30

Lamella Location

Answer 30

Mature compact bone formed by bone matrix

covered by osteogenic cells (bone forming)

Question 31

Periosteum

Answer 31

2 layered CT
Outer fibrous layer-dense CT
Sharpey’s fibers
Inner cellular layer - bone cells, precursors vasculature
LOCATION: surrounds external surface of compact bone

Question 32

Endosteum

Answer 32

1 layer CT sheath
Cellular layer - bone cells, precursors vasculature
Surrounds internal surface of bones (compact + all trabecular)
- only has a cellular layer

Question 33

Osteon

Answer 33

Bone - vascularized tissue
min/homeostasis of bone requires:
blood supply, bone-forming cells, minerals
Capillary = central feature of each osteon
cylindrical structure, oriented PARALLEL to long axis of bone