Developmental Bone Disorders Flashcards
___ ___ includes several rare disorders of bone characterized by defective ___, which results in abnormal bone mineralization and low bone density (___).
Osteogenesis Imperfecta; collagen; osteopenia
Brittle bone disease
osteogenesis imperfecta
Osteogenesis imperfecta can be autosomal dominant or recessive. ___% are autosomal dominant and some cases are sporadic.
90
Where is the mutation for osteogenesis imperfecta?
collagen gene
T/F. Bones are very fragile and fracture easily, but the degree of fragility varies with the type of OI
True.
T/F. OI is one of the least common heritable bone diseases.
False, it’s one of the most common.
Clinical features of OI include ___ sclera, ___ loss, craniofacial alterations (CLIII occlusion, traingular facies), ___ deformity of long bones, and ___ teeth.
blue; hearing; bowing; opalescent
OI’s dental alterations are ___ to dentinogenesis imperfecta. Blue, yellow or brown translucences of teeth (noticed easier in ___ teeth). Severe ___ leading to loss of VDO and potential tooth loss.
identical; primary; attrition
Radiographically, OI has “___ teeth” or premature ___ obliteration. Tooth roots ___ or ___ ___ shaped.
shell; pulpal; narrow; corn cob
OI and dentinogenesis imperfecta are distinct mutations, different diseases with different tooth alterations and have blue sclera.
False, OI and dentinogenesis imperfecta can have SIMILAR tooth alterations and blue sclera but they are distinct mutations, different diseases
How do you designate dental defects associated with OI?
opalescent teeth
“Dentinogenesis imperfecta” is reserved for alterations isolated to the teeth.
How is OI treated?
- physiotherapy, rehabilitation, orthopedic surgery
- minimize factors that cause fractures
- intravenous bisphosphonates
What is typically administered to children with moderate to severe disease pain?
intravenous bisphosphonates
What does the prognosis depend on for OI patients?
type of OI
expression of the gene
How does death result in OI patients with severe forms of the disease?
passage though the birth canal
What is a rare inherited bone disease caused by lack of osteoclastic activity?
osteopetrosis
Osteopetrosis has an ___ in bone density due to failure of ___ to function normally with continued bone formation and ossification.
increase; osteoclasts
T/F. Osteopetrosis has autosomal dominant and recessive forms.
True. The recessive is much worse
What is seen on CT imaging with osteopetrosis?
thickening of bones of skull
What is commonly seen in the autosomal recessive form of osteopetrosis?
- blindness and deafness (cranial nerve compression)
- fractures
- osteomyelitis of the jaw
___ spaces are filled in by dense bone, resulting in loss of hematopoietic precursor cells leading to ___
Marrow; pancytopenia
- increased susceptibility to infection
- osteomyelitis of the jaw
What is a frequent complication of tooth extraction?
osteomyelitis
In osteopetrosis, radiographs show diffuse density of the ___. Tooth ___ are difficult to visualize due to density of surrounding bone.
skeleton; roots
In osteopetrosis, tooth eruption in common.
False, FAILURE OF tooth eruption is common
How is osteopetrosis treated?
supportive measures (transfusions and antibiotics) bone marrow transplant (limited success)
What are some alternative therapies of osteopetrosis?
interferon with calcitriol
restricted Ca++ intake, corticosteroids and erythropoietin
Prognosis of osteopetrosis is ___ for AR form with many patients dying before ___ years of age. ___ can have long term survival.
poor; 20; AD
What is an uncommon autosomal dominant disorder that affects skull, jaws, and clavicles?
cleidocranial dysplasia
How do patients with cleidocranial dysplasia present?
prominent forehead; hypoplastic midface
Why are primary dentition retained in patients with cleidocranial dyplasia?
because permanent teeth do not erupt
numerous impacted permanent and supernumerary teeth (plenty of teeth just not erupting in the correct space or not erupting at all)
What is today’s treatment for cleidocranial dysplasia?
combined surgical and orthodontic care to correct skeletal relations, remove supernumerary teeth and bring permanent teeth into proper relation
T/F. The prognosis is poor for cleidocranial dysplasia.
False, it is good. the life span of these patients is essentially normal
Where is osteoporotic bone marrow defect found?
usually seen in the body of mandible, usually at old extraction sites
T/F. Osteoporotic bone marrow defect is an incidental finding in middle aged, asymptomatic females.
True.
What is the pathogenesis of osteoporotic bone marrow defect?
unknown, may resemble metastatic disease (biopsy)
Microscopically, ___ and ___ marrow is seen in osteoporotic bone marrow defects.
fatty; hematopoietic
What is seen on pans of osteoporotic bone marrow defect? What about periapical radiographs?
pan: radiolucent, circumscribed
PA: ill-defined borders and fine central trabeculations
What are several other terms for idiopathic osteosclerosis?
dense bone island
enostosis
Idiopathic osteosclerosis is very ___ with no expansion. What region is most common?
radiopaque (dense viable bone microscopically)
premolar-molar
Describe the margins of idiopathic osteosclerosis.
margins may be sharp or blend with adjacent bone.
With idiopathic osteosclerosis, past studies did not distinguish the idiopathic lesions from those of inflammatory origin and confusion in terminology has resulted. What 3 disorders can it be confused with?
- condensing osteitis
- hypercementosis
- cemetoblastoma
T/F. Cherubism is an autosomal recessive condition detected in childhood.
False, it is autosomal DOMINANT or de novo mutation detected in childhood
Cherubism is a ___, bilateral expansion of the jaws, especially in the ___ that results in chubby cheeks.
painless; mandible
What causes the “eyes upturned to heaven” appearance seen in Cherubism?
involvement of the inferior and/or lateral orbital walls may tilt the eyeballs upward and retract the lower eyelid, thereby exposing the sclera below the iris to produce an “eyes upturned to heaven” appearance.
How does the radiograph look for patients with Cherubism?
bilateral multilocular radiolucencies of posterior mandible with often significant displacement of teeth.
In Cherubism, microscopically, there is edematous cellular ___ connective tissue, relatively sparse benign ___ ___ cells, and sometimes ___ ___.
fibrous connective; multinucleated giant; perivascular hyalinization
What is perivascular hyalinization?
eosinophilic cuffing
T/F. In Cherubism, optimal treatment has not been determined and surgical intervention has been known to accelerate the growth of some lesions.
True.
T/F. In Cherubism, many cases seem to progress into adulthood.
False, many cases seem to involute during puberty
What is another name for simple bone cyst?
traumatic bone cyst
What is an idiopathic condition seen in the 1st and 2nd decade with a questionable relation to trauma?
simple bone cyst
Simple bone cyst has a ___ predilection and is found in the ___ ___.
male; posterior mandible
Describe the radiograph seen with simple bone cyst.
well-circumscribed radiolucency, that can scallop between roots
What is found at surgical exploration in patients with simple bone cyst?
an empty cavity is found within the bone making it difficult to obtain lesional tissue.
In simple bone cyst, ___ of bone are lined by chronically inflamed granulation tissue.
fragments
T/F. Simple bone cyst is a true cyst.
False, it has no epithelial lining and therefore, it is not a true “cyst”.
What is recommended for simple bone cyst treatment?
to enter the lesion, establish the diagnosis, then induce bleeding (supposedly the hemorrhage organizes and the lesion heals)
T/F. Simple bone cyst are ONLY found in the mandible.
False, they have been reported in almost every bone of the body.
What disease is also known as Paget disease of bone?
Osteitis deformans
Osteitis deformans has abnormal ___ and deposition, resulting in distortion of bone. The affected bones become ___ and ___.
resorption; thickened; weak
How is osteitis deformans discovered?
incidentally on routine blood test or dental radiographs
T/F. Osteitis deformans is seen in young, black female patients under 40
False, it is seen in older patients of Anglo-Saxon decent, it is rare in patients under 40 and it is more common in males (2:1)
Although the etiology is unknown, what markers are elevated in osteitis deformans?
markedly elevated serum alkaline phosphatase
Although symptoms vary in osteitis deformans, at presentation, bone pain is present in up to ___%
40
Most cases of osteitis deformans are ___, with involvement of ___ causing a “___” (monkeylike) stance due to bowing of the legs.
polyostotic; femurs; simian
Jaws are involved in ___% of patients affected with Osteitis deformans.
17
T/F. The mandible is involved more than the maxilla in osteitis deformans.
False, the MAXILLA is affected more.
What is seen radiographically in osteitis deformans?
cotton-wool appearance
hypercementosis of teeth
How is the “mosaic” pattern produced in osteitis deformans?
irregular trabeculae with resting reversal lines rimmed by osteoclasts and osteoblasts
What is the marrow replaced by in osteitis deformans?
vascular fibrous connective tissue
T/F. Osteitis deformans is chronic and progressive, but usually not life threatening.
True
What is the treatment for Osteitis deformans?
if asymptomatic, no tx
bisphosphonates
patients should be monitored for the development of giant cell tumor or bone as well as malignant bone tumors, especially osteosarcoma.
What are some potential dental complications in patients with osteitis deformans?
- difficulties in extracting teeth with hypercementosis and/or ankyloses
- extensive hemorrhage from oral surgical procedures performed during vascular lytic phase
- poor wound healing with increases susceptibility to osteomyelitis during the avascular sclerotic phase
- edentulous patients may require new dentures periodically to compensate for progressive alveolar enlargement
- pagetic bone and a history of bisphosphonate therapy generally considered unfavorable factor for osseointegration of dental implants
What are the two types of fibro-osseous lesions of the jaws?
- fibrous dysplasia
2. cement-osseous dysplasia
What are the three types of cement-osseous dysplasias?
- focal cement-osseous dysplasia
- periapical cement-osseous dysplasia
- florid cement-osseous dysplasia
Fibrous dysplasia is a ___, tumor-like lesion due to post-zygotic mutation of a ___ ___ gene (GNAS1) usually present in the first or second decade?
developmental; tumor suppressor
What percentage of fibrous dysplasia are monstotic (affecting one bone)?
70-85%
T/F. Fibrous dysplasia is a painful bilateral fast-growing swelling.
False, it is a painLESS, UNILATERAL, SLOW-growing swelling
The ___ are among the most commonly affected bones in fibrous dysplasia. The ___ is affected more than the ___.
jaws; maxilla; mandible
What is a more severe form of fibrous dysplasia?
“craniofacial fibrous dysplasia”
“Craniofacial fibrous dysplasia” has ___ lesions may involve the adjacent facial bones, including the ___, ___, and ___, which results in marked facial deformity.
maxillary; sphenoid; zygoma; occiput
What is the classic radiographic description for fibrous dysplasia?
Describe the radiograph in these patients.
ground glass pattern
poorly defined, blending margins
early stages - radiolucent or mottled
T/F. With maxillary involvement, obliteration of the maxillary sinus is common in fibrous dysplasia patients.
True.
In fibrous dysplasia, microscopically there is irregularly shaped ___ of immature (woven) bone. The abnormal bone fuses to adjacent normal bone but no ___ is formed. The is also moderate cellular ___ connective tissue.
trabeculae; capsule; intertrabecular
What are the two presentations of polyostotic fibrous dysplasia?
- jaffe type
2. McCune Albright type
The jaffe type has two or more bones affected in conjuction with ___-__-___ spots that have ___ borders (like the coast of ___)
café-au-lait; jagged; Maine
In McCune-Albright, patients have two or more bones affected in addition to café-au-lait pigmentation and ___ disturbances which manifest as precocious puberty.
endocrine
In fibrous dysplasia, ___ lesions may not need treatment or may be removed by ___ ___ resection.
small; en bloc
T/F. Significant cosmetic or functional deformity may require an attempt at surgical reduction in fibrous dysplasia. Sometimes the disease stabilizes with skeletal maturation.
True.
What percentage of surgically treated fibrous dysplasia lesions show regrowth, particularly in younger patients?
25-50%
In fibrous dysplasia, malignant transformation to a mesenchymal malignancy is ___ and usually is reported in lesions that have received ___ therapy
rare; radiation
What is a benign, possibly reactive process that may originate from the periodontal ligament fibroblast?
Cemento-ossesous dysplasia
What groups is cement-ossesous dysplasis seen in?
most commonly African-American females then
East Asian females
White females
but it can affect either sex and any ethinic group
Place the different types of cement-osseous dysplasias in order of severity:
- Periapical cemento-osseous dysplasia
- Focal cemento-osseous dysplasia
- Florid cemento-osseous dysplasia
A. Mild
B. Moderate
C. Severe
1 - A
2 - B
3 - C
Describe a radiograph of a patient with cemento-osseous dysplasia.
- found incidentally
- tooth bearing areas of the jaw (above IAN)
- varies from completely radiolucent to densely radiopaque with a thin peripheral radiolucent rim (PDL remains in tact)
- TEETH TEST VITAL!!!
Periapical cemento-osseous dysplasia is found in the ___ anterior region or ___-aged ___-American women.
mandibular; middle; African
T/F. Periapical cemento-osseous dysplasia has radiolucencies at apices of teeth with gradual central opacity developing.
True.
What can be confusing with hypercementosis?
radiodensity is all within the PDL
What is confusing with idiopathic osteosclerosis?
not necessarily at apex; no lucent periphery
What is confusing about benign cementoblastoma?
resorption of root and fusion with radiopaque mass, usually affecting one posterior tooth
How is Periapical Cemento-osseous dysplasia diagnoses, treated and what is its prognosis?
diagnosis: based on clincal and radiographic features
treatment: none necessary
prognosis: excellent
In the past, what true neoplasm was focal cemento-osseous dysplasia confused with?
the central cemento-ossifying fibroma
FCOD is seen across all ethnic groups but may affect a greater proportion of ___.
whites (that may be a study population bias)
T/F. FCOD is less common than central cemento-ossifying fibroma, but they are seen in a similar demographic group - older adult men.
False, FCOD is MORE common than central cemento-ossifying fibroma, but they are seen in a similar demographic group - YOUNGER adult WOMEN.
How is FCOD detected? What is seen?
Radiographic examination
unilocular radiolucency, with or without radiopaque central component
FCOD is found in the ___ of the ___, mostly in ___. The most common age range is ___-___. Swelling or discomfort is ___.
body; mandible; females; 20-40; unusal
With FCOD, at surgery the lesion is usually ___ defined from the surrounding bone and multiple, small gritty ___ are obtained.
poorly; fragments
In FCOD, connective tissue with embedded mineralized tissue that resembles either ___ bone or cellular ___.
woven; cementum
How do the trabeculae appear in FCOD?
ginger root shaped
T/F. FCOD treatment is unnecessary, however biopsy is often warranted to rule out other diseases.
True
FCOD prognosis is generally ___, although a lesion that initially appears as a focal process may in fact represent the first sign of what disease?
good; florid cemento-osseous dysplasia
What is the most severe expression of the cemento-osseous dysplasias?
Florid cemento-osseous dysplasia
Florid is seen in middle-aged or older ___-American ___.
African; women
Florid affects multiple ___ of the jaws. It is generally asymptomatic unless overlying mucosa ___, resulting in ___.
quadrants; ulcerates; sequestration
Florid has radiolucencies with multiple “___ ___” radiopacities in at least ___ quadrants of the jaws.
cotton wool; two
Over time, Florid lesions become more ___. They may also be associated with what disease?
radiodense; simple (traumatic) bone cysts
With cemento-osseous dysplasia, lesions tend to be ___ and prone to ___ and secondary ___ with minimal provocation.
hypovascular; necrosis; infection
T/F. Dental implant placement is not recommended in cemento-ossesous dysplasia patients.
True
In Florid, ___ is not necessary and submission of sequestrating fragments shows densely ___ tissue with ___ debris and inflammation.
biopsy; mineralized; necrotic
T/F. Patients with cemento-osseous dysplasia should be encouraged to remove their teeth. Why?
False, Patients with cemento-osseous dysplasia should be encouraged to RETAIN their teeth.
Why? symptoms begin after lesion exposure resulting from progressive alveolar atrophy under a denture.
When does the onset of symptoms occur in cemento-osseous dysplasia?
associated with exposure to sclerotic masses to the oral cavity (biopsy, elective tooth extraction). Therefore, these should be avoided
If bone is exposed in cemento-osseous dysplasia, ___, ___ ___ -like material begins to exfoliate through the oral mucosa?
yellowish, avascular cementum
What is recommended for asymptomatic patients with Cemento-osseous dysplasia?
regular recall examinations with prophylaxis and oral hygiene reinforcement to control periodontal disease and prevent tooth loss
Management of symptomatic Cemento patients who develop secondary ___ is difficult. Treatment consist of ___ and ___ (which are indicated but not effective because they can’t get to the infection)
osteomyelitis; debridement; antibiotics
What is overall prognosis of Cemento-osseous dysplasia? What causes secondary infection?
good
sequestration, requiring debridement and antibiotics
T/F. Development of sarcoma within an area of cemento-osseous dysplasia is common.
False, it has been reported but is extremely rare.
