bone pathologies

Question 1

Osteogenesis imperfecta (OI)

Answer 1

most common
mutation in genes that form collagen
bone fragility and repeated bone fractures
brittle bone disease
type I collagen (impaired collagen synthesis)
dentinogenesis imperfecta, blue sclera

Question 2

OI type I

Answer 2

mild from
insufficient quantity, normal quality
blue sclera
open bite
wormian bones

Question 3

OI type II

Answer 3

lethal form
insufficient quality and quantity
dead within first month of life

Question 4

OI III

Answer 4

defective quality

muscle weakness, growth retardation, early death

Question 5

OI IV

Answer 5

defective quality
do not fit other categories
short stature, period of fractures

Question 6

dentiogenesis imperfecta (DI)

Answer 6

hereditary
tooth discoloration (opalescent)
enamel fracture
bulbous crowns

Question 7

DI type I

Answer 7

associated with OI

primary teeth more than permanent

Question 8

DI type II

Answer 8

not associated with OI

both primary and permanent equally affects

Question 9

DI type III

Answer 9

thin dentin, enormous pulp chamber
shell teeth
extremely rare

Question 10

osteopetrosis

Answer 10

hereditary
marked increase in bone density
failure of normal osteoclast function
skeletal fragility, haematopoietic insufficiency, nerve entrapment syndrome, growth impairment

Question 11

infantile osteopetrosis

Answer 11

poor prognosis 
failure to thrive and grow
cranial nerve entrapment 
delayed dentition
pancytopenia (defective osseous tissue tends to replace bone marrow which may lead to bone marrow failure)

Question 12

adult osteopetrosis

Answer 12

good prognosis
diagnosed based on radiographs
bone pain, fractures, cranial entrapment
bone marrow functions normally

Question 13

cleidocranial dysplasia (CCD)

Answer 13

genetic
affect CBFA1 (guiding intramembranous bone formation and dentinogenesis)
shoulder hyper mobility
multiple unerupted teeth

Question 14

CCD jaw changes

Answer 14

high palatal arch
coarse trabeculation
mandibular rami is nearly parallel -sided anterior and posterior borders
coronoid processes may be slender and pointed with a distal curve

Question 15

benign fibro-osseous lesions

Answer 15

focal or diffuse replacement of normal bone by fibrovascular tissue
bone is weakened and prone to expansion
FD, PCOD, FCOD

Question 16

fibrous dysplasia (FD)

Answer 16

Monostotic (affecting a single bone)
Polyostotic (affecting several bones, cafe au lait spots=Jaffe type, hyperfunctioning endocrine, stunted growth, precocious puberty = McCune-Albright syndrome)
craniofacial type (maxilla, sinuses, occipital bone)
ground glass radio graphic appearance

Question 17

Periapical Cemento-Ossifying Dysplasia (PCOD)

Answer 17

focal type
florid type
PCOD predilection (females, african americans, lower anterior mand region)

Question 18

PCOD characteristics and stages

Answer 18

assymptomatic, incidentally on radiographs
Early lesions (radiolucency at apices of teeth)
lesions tend to mature (mixed lesion on radiographs)
seldom exceed 1.0cm in diameter
self-limiting

Question 19

florid cemento-osseous dysplasia (FCOD)

Answer 19

multi-quadrant radio-opaque cementum like masses
assymptomatic
multiple masses within a peripheral radiolucent rim

Question 20

Cherubim

Answer 20

genetic, rare
increased activity of osteoclasts and osteoblasts
bilateral expansion of the mand (bone is replaced with fibrovascular connective tissue)
early primary tooth loss, uneruption of permanent teeth
varying degrees of remission

Question 21

Paget’s disease of bone (PD)

Answer 21

chronic condition
abnormal, woven bone (cotton-wool appearance)
sporadic and hereditary types
enlargement of skull bone
neuro-compression, elevated serum alkaline phosphate
males
50 yrs or older
chronic, slow progression (NSAIDs, calcitonin and bis-phosphonates)