Schricker

Question 1

Calcium is important for

Answer 1

Clotting
Muscle contraction
Cardiovascular function

Question 2

Primary regulators of serum calcium

Answer 2

Parathyroid hormone
Calcitonin
Vitamin D

Question 3

Bone is a _____

Answer 3

Composite

Calcium reservoir

Question 4

Composition of bone…Which is strong, which is tough?

Answer 4

Collagen - Tough but not strong

Hydroxyapatite - Strong but not tough (brittle)

Question 5

Enamel matrix is _______

Percentage hydroxyapatite = ?

Answer 5

Amelogenin

90%

Question 6

Dentin matrix is ______

Percentage hydroxyapatite = ?

Answer 6

Type I collagen

67%

Question 7

Difference between bone and teeth

Answer 7

Bone can heal, enamel cannot (can remineralize)
Dentin has limited capacity to heal
Bone has lower mineral content
Bone is vascularized

Question 8

Process of mineralization

Answer 8

• Crystallization initiates & ruptures vesicles with saturated solution of HA
• Osteoblasts excrete matrix proteins
• Pyrophosphate can block mineralization, but alkaline phosphatase degrades pyrophosphate

Question 9

Factors that influence balance of building & resorbing bone

Answer 9

Serum calcium
Hormones
Cytokines

Question 10

Signals that promote resorption

Answer 10

Parathyroid hormone
Prostaglandin
IL-1, IL-6, TNF
Prolactin
Corticosteroids
Vitamin D

Question 11

Signals that inhibit resorption

Answer 11

Calcium
Estrogens
Calcitonin
Tumor growth factor-beta
IL-17

Question 12

Osteoblasts originate from

Answer 12

Mesenchymal stem cell -> Preosteoblast

Question 13

Osteoclasts originate from

Answer 13

Hematopoietic stem cell -> Monocyte macrophage -> Preosteoclast

Question 14

Osteoclast activation by

Answer 14

RANK receptors on osteoclast precursors recognize RANKL (RANK ligand)

Question 15

Distribution of calcium

Answer 15

99% is contained in mineralized tissue

1% is circulated in a bound or ionic form