Bone Disorders - part I Flashcards
1
Q
inherited bone disorders
A
- osteogenesis imperfecta
- osteopetrosis
- cleidocranial dysplasia
- cherubism
2
Q
acquired bone disorders
A
- osteitis deformans (Paget disease)
- fibro-osseous lesions of the jaw: fibrous dysplasia
- fibro-osseous lesions of the jaw: cemento-osseous dysplasia (COD)
- osteoporotic bone marrow defect
- idiopathic osteosclerosis
- simple bone cyst
3
Q
osteogenesis imperfecta
A
“brittle bone disease”
several rare disorders of bone
4
Q
what does defective collagen in osteogenesis imperfecta cause?
A
defective collagen –> abnormal bone mineralization –> low bone density (osteopenia)
5
Q
etioloigy of osteogenesis imperfecta
A
mutation in collagen gene
6
Q
T/F: osteogenesis imperfecta can be autosomal dominant or recessive
A
true
7
Q
T/F: a majority of osteogenesis imperfecta cases are autosomal recessive
A
false, 90% are autosomal dominant
8
Q
T/F: some of the osteogenesis imperfecta are sporadic
A
true
9
Q
T/F: osteogenesis imperfecta is one of the most common heritable bone diseases
A
true
10
Q
why does the severity of osteogenesis imperfecta widely varies?
A
it depends on mutation
11
Q
clinical features of osteogenesis imperfecta
A
- bones fragile, fracture easily; varies widely with the type of mutation
- blue sclerae
- hearing loss
- Bowing deformity long bones
- craniofacial alterations (CL III occlusion, triangular facies)
12
Q
dental alterations of OI that are identical to dentinogenesis imperfecta
A
- blue, yellow or brown translucence (more noticeable in primary teeth)
- opalescent teeth
- severe attrition leading to loss of VDO and potential tooth loss
13
Q
T/F: OI and dentinogenesis imperfecta can have similar tooth alterations and blue sclerae, but they are distinct mutations, different diseases
A
true
14
Q
dental defects associated with OI should be designated as what?
A
“opalescent teeth”
15
Q
T/F: “dentinogenesis imperfecta” is reserved for alterations isolated to the teeth
A
true
16
Q
T/F: OI can appear identical to dentinogenesis imperfecta radiographically
A
true
17
Q
radiographic features of osteogenesis imperfecta
A
- “shell teeth”, or premature pulpal obliteration
2. narrow or “corn cob” shaped roots
18
Q
treatment for osteogenesis imperfecta
A
- physiotherapy/rehabilitation
- orthopedic surgery
- minimize factors leading to fracture
- IV bisphosphonates for children with moderate-severe pain
19
Q
why are IV visphosphonates indicated for children with moderate-severe pain?
A
reduce fracture rates
20
Q
treatment for dentition of osteogenesis imperfecta
A
- crown/bridge
- partial or complete dentures
- ± implants
- orthognathic surgery
- orthodontics
21
Q
prognosis of osteogenesis imperfecta depends on what?
A
- mutation
2. expression of the gene
22
Q
what is the range of prognosis for osteogenesis imperfecta?
A
ranges from minimal bone deformity with essentially normal growth to severe forms leading to death from passage through the birth canal
23
Q
T/F: osteopetrosis have several forms, both autosomal dominant and recessive
A
true
24
Q
T/F: autosomal dominant form of osteopetrosis is more severe
A
false, recessive more severe
25
what happens when osteoclasts fail to fxn normally?
bone is not resorbed
26
what will happen if bone continued to form and ossify in osteopetrosis?
increased bone density
27
pancytopenia
loss of hematopoietic precursor cells
28
what happens when pancytopenia occurs in osteopetrosis?
increased susceptibility to infections and osteomyelitis
29
T/F: osteopetrosis is rare
true
30
clinical features of osteopetrosis
1. blindness and deafness due to CN compression
2. fractures
3. osteomyelitis
31
what is the cause of frequent complication of tooth extraction in osteopetrosis pts?
osteomyelitis
32
radiographic findings of osteopetrosis
1. diffuse density of skeleton
2. marrow spaces filled in by dense bone
3. tooth roots difficult to visualize due to surrounding dense bone
4. failure of tooth eruption
33
tx of osteopetrosis
1. supportive measures
2. bone marrow transplant
3. alternative therapies
34
supportive measures for osteopetrosis
transfusions and abx when necessary
35
alternative therapies for osteopetrosis
1. interferon with calcitriol
2. restriction of Ca2+ intake
3. steroids
36
T/F: autosomal dominant form of osteopetrosis can have long-term survival
true
37
what is the prognosis for autosomal recessive form of osteopetrosis?
poor
38
T/F: patients with the autosomal recessive form of osteopetrosis usually die before 20 y.o.
true
39
T/F: cleidocranial dysplasia is autosomal recessive
false, autosomal dominant
40
T/F: spontaneous mutations have also been reported for cleidocranial dysplasia
true
41
T/F: investigators have proposed an autosomal recessive form of cleoidcranial dysplasia
true
42
T/F: cleidocranial dysplasia is common
false, uncommon
43
where does the cleidocranial dysplasia primarily affect?
1. skull
2. jaws
3. clavicles
44
clinical features of cleidocranial dysplasia
1. prominent forehead, hypoplastic midface
2. long neck
3. shoulders narrow and drooping (hypoplastic or missing clavicles)
4. hypermobility of shoulders
45
dental findings of cleidocranial dysplasia
1. primary dentition retained because permanent teeth don't erupt
2. numerous impacted and supernumerary teeth (i.e. plenty of teeth; not erupting in the correct space, or, not erupting at all)
46
tx for cleidocranial dysplasia
combined surgical and orthodontic care to
1. correct skeletal relations
2. remove supernumerary teeth
3. correct alignment of permanent teeth
47
prognosis of cleidocranial dysplasia
good
48
T/F: life span of ppl with cleidocranial dysplasia is essentially normal
true
49
T/F: cherubism is autosomal recessive
false, autsomal dominant
50
T/F: cherubism has limited expressivity
false, variable
51
when is cherubism detected?
in childhood
52
clinical features of cherubism
1. painless bilateral expansion of jaws, especially mandible
2. chubby cheeks
3. involvement of inferior and/or lateral orbital walls may tilt the eyeballs upward and retract lower eyelid "eyes upturned to heaven"
53
T/F: cherubism involves the maxilla more frequently
false, less frequently
54
radiographic features of cherubism
1. bilateral multilocular radiolucencies posterior mandible, maxilla
2. often significant displacement of teeth
55
T/F: cherubism is occasionally appears unilocular in radiographs
true
56
histopathologic features of cherubism
1. cellular fibrous CT
2. sparse benign-appearing multinucleated giant cells
3. may see perivascular hyalinization
57
tx for cherubism
1. optimal tx has not been determined
| 2. surgical intervention sometimes accelerates growth of lesions
58
T/F: many cherubism cases involute during puberty
true
59
T/F: pts with cherubism will have persistent facial deformity or continued disease progression
true
60
etiology of osteitis deformans (Paget disease)
unknown
61
osteitis deformans (Paget disease)
abnormal resorption and deposition, resulting distored, weaker bone
62
what happens to the affected bones in Paget disease?
becomes thickened
63
T/F: Paget disease is often discovered incidentally on routine blood test or dental radiographs
true
64
Paget disease is primarily of what ancestry?
Anglo-Saxon
65
T/F: Paget disease has a 2:1 female predilection
false, 2:1 MALE predilection
66
who is affected by Paget disease?
older pts, rare <40 y.o.
67
40% of Paget disease cases have what in common?
bone pain
68
clinical features of Paget disease
1. "Simian" (monkey-like) stance if femurs involved
2. elevated serum alkaline phosphatase
3. skull involvement - progressive enlargement, "hate won't fit"
69
what happens if femur is involved in Paget disease?
bowing of legs
70
T/F: most Paget disease cases are polyostotic
true
71
what happens to the jaw if involved in Paget disease?
thickened, enlarged alveolar bone "dentures don't fit"
72
radiographic features of Paget disease
1. "cotton wool" appearance of bone
| 2. may have extensive hypercementosis
73
histopathologic features of Paget disease
1. "Mosaic" pattern of irregular trabeculae with resting and reversal lines
2. marrow replaced by vascular fibrous CT
74
tx for Paget disease if asymptomatic
no tx
75
Paget disease if symptomatic
bisphosphonates
76
T/F: Paget disease is chronic and progressive, but usually not life-threatening
true
77
what should pts with Paget disease be monitored for?
development of a giant cell tumor or malignant tumors esp osteosarcoma
78
why would an extraction be difficult on pts with Paget disease?
difficulty extracting teeth w hypercementosis and/or ankylosis
79
what is a dental complication during the vascular/lytic phase for pts with Paget disease?
hemorrhage
80
poor wound healing in pts with Paget disease increases susceptibility to what during avascular/sclerotic phase?
osteomyelitits
81
T/F: new dentures may be required periodically for pts with Paget disease
true
82
T/F: implant placement is generally favorable for pts with Paget disease
false, unfavorable and more so with use of bisphosphonates
83
etiologies of fibro-osseous lesions
1. developmental (hamartomatous)
2. reactive
3. dysplastic
4. neoplastic
84
fibro-osseous lesions
1. fibrous dysplasia
| 2. cemento-osseous dysplasia (COD)
85
T/F: fibrous dysplasia is a post-zygotic mutation
true
86
post-zygotic mutation of fibrous dysplasia
1. pluripotent stem cell
2. skeletal progenitor cell
3. post-natal life
87
what determines the extent of fibrous dysplasia
time of occurrence of mutation
88
when does fibrous dysplasia presents?
~1st-2nd decade (younger than Paget disease)
89
T/F fibrous dysplasia has a female predilection
false, NO gender predilection
90
T/F: fibrous dysplasia can be polyostotic or monostotic, but a majority of the cases are polyostotic
false, 75-80% monostotic
91
clinical features of fibrous dysplasia
1. painless, unilateral swelling
2. slow growth
3. craniofacial fibrous dysplasia
92
which bone is most commonly affected by fibrous dysplasia?
jaws
93
T/F: mandible is more often affected by fibrous dysplasia than maxilla
false, maxilla > mandible
94
craniofacial fibrous dysplasia lesions may involve what?
adjacent facial bones
95
what may craniofacial fibrous dysplasia result in?
marked facial deformity
96
how are the early stages of fibrous dysplasia seen radiographically?
radiolucent or mottled
97
radiographic features of fibrous dysplasia
1. opacify as they grow
2. obliteration of maxillary sinus
3. classic "ground glass" pattern
4. poorly defined, blending margins
98
what are the 2 types of polyostotic fibrous dysplasia?
1. Jaffe type
| 2. McCune-Albright type
99
Jaffe type of polyostotic fibrous dysplasia
2 or more bones affected and cafe-au-lait spots with jagged borders (coast of Maine)
100
McCune-Albright type of polyostotic fibrous dysplasia
2 or more bones affected by fibrous dysplasia, cafe-au-lait spots and endocrine disturbances
101
what is the result of endocrine disturbances in McCune-Albright type of polyostotic fibrous dysplasia
precocious puberty
102
histopathologic features of fibrous dysplasia
1. irregular-shaped trabeculae of immature (woven) bone in cellular fibrous stroma
2. no capsule - abnormal bone fuses to adjacent normal bone
103
tx for fibrous dysplasia if lesion(s) are small
none
104
when should surgery be delayed for fibrous dysplasia?
until disease quiescent
105
tx for fibrous dysplasia
1. surgical reduction if cosmetic or functional problem
| 2. en-bloc resection
106
what is contraindicated in txing fibrous dysplasia?
radiation
107
T/F: sometimes fibrous dysplasia stabilizes with skeletal maturation
true
108
T/F: surgically treated fibrous dysplasia lesions show regrowth esp in younger pts
true
109
T/F: malignant transformation of fibrous dysplasia is rare ans is usually in lesions which have received radiation
true
