BONE BIOLOGY BISPHOSPHONATES

Question 1

What regulates bone turnover?

Answer 1

parathyroid hormone
calcitriol
calcitonin
sex hormones
GH
thyroid hormone
cortisol

Question 2

role of osteoblasts

Answer 2

produce bone

Question 3

role of osteoclasts

Answer 3

resorb bone

Question 4

5 phases in bone remodeling

Answer 4

1. activation
2. osteoclast recruitment and resorption
3. reversal
4. osteoblast recruitment and bone formation
5. termination - quiescence

Question 5

list 2 genetic abnormalities of bone

Answer 5

osteogenesis imperfecta
osteopetrosis

Question 6

list 5 non-genetic abnormalities of bone

Answer 6

osteoporosis
glucocorticoid-induced osteoporosis
hyperparathyroidism
Pagets disease
fibrous dysplasia

Question 7

what bones does OI affect? and its aetiology

Answer 7

whole skeleton
collagen defect

Question 8

what is osteopetrosis?

Answer 8

osteoclastic bone resorption defect

Question 9

who does pagets disease commonly present in?

Answer 9

elderly

Question 10

how may a mandible present on a DPT of someone with OI?

Answer 10

thin and narrow

Question 11

how may a DPT present in a pt with osteopetrosis?

Answer 11

marble bone disease - bone is dense and sclerotic (dentition cant erupt)

Question 12

what is a sequestrum

Answer 12

section of necrosed bone detached from healthy tissue

Question 13

what happens to bone following xLA

Answer 13

physiological osteoclastic bone resorption

Question 14

following xLA where is the greatest amount of bone loss?

Answer 14

horizontal dimension
facial aspect ridge

Question 15

how long does the bone remodeling process take?

Answer 15

6 months

Question 16

definition of atrophic mandible

Answer 16

height < 15mm

Question 17

list 4 drug groups affecting bone remodelling

Answer 17

bisphosphonates
denosumab and anti-angiogenic drugs
steroids
NSAIDs

Question 18

bisphosphonate action

Answer 18

bind avidly to exposed bone mineral around resorbing osteoclasts = high levels in the resorption lacunae

Question 19

why are bisphosphonates maintained in the bone for long periods of time

Answer 19

they aren’t metabolised

Question 20

describe the term anti-angiogenic

Answer 20

effect vasculature of area which inhibits bone remodeling

Question 21

2 classes of bisphosphonates and give example for each

Answer 21

non-nitrogen containing - clodronate
nitrogen containing - alendronate

Question 22

list 4 main conditions treated with bisphosphonates

Answer 22

multiple myeloma
breast cancer
osteoporosis
prostate cancer

Question 23

according to the SDCEP guidelines, what classifies a pt as being low risk in relation to bisphosphonates and MRONJ?

Answer 23

1. not yet started taking
2. taking bisphosphonates for prevention or management of osteoporosis

Question 24

according to SDCEP guidelines, what classifies a pt as being high risk in relation to MRONJ?

Answer 24

1. previous diagnosis of MRONJ
2. taking bisphosphonates as part of the management of a malignant condition
3. other non-malignant condition of the bone - PAGETS DISEASE
4. under the care of a specialist for rare condition - OI
5. concurrent use of systemic corticosteroids or other immunosuppressants
6. coagulopathy, chemotherapy, radiotherapy

Question 25

when would you review a low risk pt?

Answer 25

4 weeks

Question 26

what is the 3 criteria for MRONJ?

Answer 26

1. current or previous tx with bisphosphonates, antiangiogenic drugs or RANKL inhibitors 2. exposed bone in the maxillofacial region/ bone that can be probed that has persisted for more than 8 weeks 3. no history of radiation therapy to the jaws

Question 27

signs and symptoms of MRONJ

Answer 27

area of necrotic exposed bone internal/ external discharging fistulas pain painless loose teeth bony sequestrae mobile teeth paraesthesia

Question 28

why does overlying mucosa to necrotic bone die

Answer 28

no periosteal supply

Question 29

trade name for denosumab?

Answer 29

Prolia

Question 30

when is optimal time for pt taking denosumab to receive xLA? and why

Answer 30

just before next injection - lowest impact on bone turnover

Question 31

how quick does denosumab work?

Answer 31

within 6 hours the osteoclast function is inhibited lasts for 6 months

Question 32

corticosteroid action

Answer 32

anti-inflammatory delay healing in strong doses

Question 33

2 examples of corticosteroids?

Answer 33

prednisolone hydrocortisone

Question 34

what conditions may high dose steroids be used to treat?

Answer 34

COPD autoimmune diseases

Question 35

2 examples of NSAIDs?

Answer 35

ibuprofen diclofenac

Question 36

can NSAIDs impact bone healing?

Answer 36

yes - avoid following bone augmentation surgery for dental implants as they interfere with production of prostaglandins

Question 37

name drugs that affect absorption of calcium from the stomach

Answer 37

anti-seizure drugs - carbamazepine, phenytoin and long term PPIs

Question 38

what group of drugs increase renal excretion of calcium?

Answer 38

diuretics

Question 39

what type of drugs increase androgen and oestrogen levels?

Answer 39

drugs for breast and prostate cancer