Developmental Bone Disorders Flashcards
Osteogenesis Imperfecta is characterized by defective _______ which results in abnormal bone _______ and low bone density (osteopenia).
collagen
mineralization
True or False: Osteogenesis Imperfecta is also known as “Brittle Bone Disease”
True
True of False: OI is a common disorder of bone.
False: it is a rare disorder of bone (overall)
*however, it is one of the most common HERITABLE bone diseases
OI is the mutation of a collagen gene. What is the inheritance type?
autosomal dominant or recessive
Is OI more commonly recessive or dominant?
90% are autosomal DOMINANT (“DOI”-dominant.O.I)
True or False: If you have OI, the degree of fragility is always rather severe.
False: Severity varies widely depending on the mutation
What are the clinical features of osteogenesis imperfecta?
blue sclera
hearing loss
craniofacial (class III occlusion/triangular facies)
bowing of long bones
translucent teeth (yellow, blue, or brown)
severe attrition leading to loss of VDO
radiographic “shell teeth” - Pulpal obliteration
Narrow roots/Corn Cob chaped
(“a B.A.T.C.H of corn shells”)
Blue/Bowing, Attrition, Translucence, Cranio, Hearing
corn cob roots
shell teeth
True or False: OI and DI have similar tooth alterations because they are similar mutations and the diseases are related.
False: Distinct mutations, Different Diseases, with similar tooth alterations
Dental defects associated with OI should be designated as _______. However, alterations that are limited only to the teeth (not bone) would be considered “______”
opalescent teeth
dentinogenesis imperfecta
What are the mainstays of treatment for OI?
physiotherapy rehabilitation orthopedic surgery minimize factors that cause fractures IV bisphosphonates (children with mod-severe pain)
True or False: Some OI patients have very minimal bone deformity and have normal growth.
True
In severe forms of OI, how could an infant die?
crushing during passage through the birth canal :(
Osteopetrosis is a (common or rare?) bone disease that is caused by a lack of _________ activity.
rare
osteoclastic
What is worse, the autosomal dominant or recessive form of osteopetrosis?
recessive
fractures and osteomyelitis are common in the AR form due to decreased vascularity/healing ability
What is the results of osteoclastic inactivity?
increased bone density
decreased osteoclast + continued bone formation
What is seen on the CT scan of a patient with osteopetrosis?
thickening of bones of the skull
Why might someone with osteopetrosis have blindness or deafness?
cranial nerve compression
True or False: Osteopetrosis leads to pancytopenia
True: Marrow spaces are filled with dense bone = loss of hematopoietic precursor cells
What are the risks associated with pancytopenia?
increased susceptibility to infection
osteomyelitis of the jaws and extraction complications
True or False: A patient with osteopetrosis could be seen clinically with draining sinus tracts or crowded teeth.
True:
infections in bone that has nowhere else to spread
bone is too dense, teeth erupt irregularly or not at all
Why is it difficult to see an osteopetrosis patient’s tooth roots in a radiograph?
difficult to discern due to the density of surrounding bone
True or False: The treatment of choice for osteopetrosis is a bone marrow transplant.
False: limited success of transplants
What is the treatment for osteopetrosis?
Supportive measures
transfusions
antibiotics when needed
alternative therapies (interferon + calcitriol + corticosteroids + erythropoietin + dec. calclium intake)
The AR osteopetrosis form has a ____ prognosis.
Poor
many patients die before age 20 years
True or False: the AD osteopetrosis form can have long-term survival.
true
Cleidocranial Dysplasia is an uncommon autosomal _____ condition that affects the development of bones and teeth.
dominant
Cleidocranial dysplasia primarily affects which bones?
jaw
skull
clavicles
True or False: Patients with cleidocranial dysplasia typically have a retained primary dentition.
True, permanent teeth don’t erupt or are impacted
they HAVE plenty of teeth (sometimes even too many) but they just don’t erupt
What are some clinical signs of cleidocranial dysplasia?
prominent forehead
hypoplastic midface
long neck
missing or hypoplastic clavicles = able to approximate shoulders
What is the treatment for cleidocranical dysplasia?
combined surgical and orthodontic care to correct skeletal relationships
removal of extra teeth- bring permanent into occlusion
True or False: the lifespan of cleidocranial dysplasia patients is normal.
true, its more of a cosmetic problem
What is an “osteoporotic bone marrow defect?”
Usually it’s an incidental finding via radiographic imaging that is asymptomatic and has an unknown pathogenesis (resembles metastatic disease)
Where are osteoporotic bone marrow defects usually seen?
in the body of the mandible
at an old extraction site
in middle age females
What are the microscopic findings of Osteoporotic Bone Marrow Defects?
Fatty and hematopoietic marrow
How does an Osteoporotic Bone Marrow Defect appear on radiographs?
Panoramic: radiolucent and somewhat circumscribed
Periapical: ill-defined borders and fine central trabeculations
In addition to “Osteoporotic Bone Marrow Defects,” what is another incidental radiographic finding?
Idiopathic Osteosclerosis
Other terms for Idiopathic Osteosclerosis include:
________
__________
Enostosis
Dense Bone Island
Idiopathic Osteosclerosis is an area of ______ on xray and is most commonly seen in the _____ region.
radiopacity (without expansion) with sharp or blended borders
premolar-molar
Idiopathic osteosclerosis is commonly mislabeled as which three conditions?
condensing osteitis
hypercementosis
cementoblastoma
How is condensing osteitis differentiated from idiopathic osteosclerosis?
condensing osteitis is an area of decay surrounding the root and has a WIDENED PDL
How is cementoblastoma differentiated from idiopathic osteosclerosis?
Cementoblastoma occurs in the cementum and therefore is a radiopacity that is SURROUNDED BY the PDL
True or False: Idiopathic Osteosclerosis appears in areas between teeth and shows no alteration in the PDL.
True
also, histiologically the bone is dense and vital
What is cherubism?
autosomal dominant condition (or de novo) that causes painless, bilateral expansion of the jaws- detected in childhood
True or False: The mandible is less likely affected by cherubism
false: mandible is common, maxilla is less frequently involved
What is the cause for “eyes upturned to heaven” appearance associated with cherubism?
involvement of the inferior/lateral orbit walls may tilt the eyeballs upward and retract the lower lids = exposing the sclera below the iris
What is the radiographic appearance of cherubism?
BILATERAL multilocular radiolucencies of posterior mandible and displacement of teeth
Microscopic evidence of cherubism includes:
______ connective tissue
_______ cells
________ hyalinization
edematous, cellular, fibrous CT
multinucleated giant cells
perivascular hyalinization
True or False: Surgical intervention is the treatment of choice for cherubism.
FALSE! it has been known to accelerate the growth of some lesions
Many cases of cherubism have _____ during puberty
involuted
Which idiopathic bone lesions has a predilection for the posterior mandible of males?
simple bone cyst (traumatic bone cyst)
Simple bone cysts have a questionable relation to _____.
trauma
What is the radiographic appearance of simple bone cysts?
well-circumscribed radiolucency that scallops between roots (lamina dura remain in tact/normal)
Upon surgical exploration of a simple bone cyst, what is found?
an empty cavity lined by chronically inflamed granulation tissue (no epithelial lining = not a “true cyst”)
What is the recommended treatment of a traumatic bone cyst?
induce bleeding within the hollow cavity to stimulate bone fill
What is Osteitis Deformans?
abnormal resorption and deposition of bone that results in thick/weak bones and distortion
(aka Paget Disease of Bone)
True or False: Osteitis Deformans is often discovered incidentally before age forty.
False: it is rare in patients <40 years old
True or False: Osteitis Deformans is more common in men.
True: men 2-to-1
deforMANs
Which enzyme in markedly elevated in osteitis deformans?
serum alkaline phosphatase
How often is bone pain associated with osteitis deformans?
40% at presentation
If a femur appears moth-eaten radiographically, what is often seen clincally in this osteitis deformans patient?
simian stance (monkey-like) due to bowing of legs
How often are the jaws affected by osteitis deformans?
17% of patients
Which is affected more often, maxilla or mandible? How does the bone look, radiographically?
maxilla
cotton-wool or moth-eaten
True of False: Osteitis deformans often presents with generalized hypercementosis of teeth
True
If a patient reports that their “hat won’t fit” or “denture stopped fitting,” what condition would you expect?
Paget Disease of Bone (osteitis deformans)
*remember, appears >40years old
How does osteitis deformans appears microscopically?
-irregular trebeculae with resting and reversal lines
“mosaic pattern”
-marrow replaced by vascular fibrous CT
-rimmed by osteoclasts/osteoblasts
What is the treatment for osteitis deformans?
asymptomatic = no tx
bisphosphonates
monitor for development of giant cell tumor of bone and osteosarcoma
What are the potential dental complications associated with osteitis deformans?
- difficulty extracting teeth
- extensive hemorrhage from oral surgery during “vascular lytic stage”
- poor wound healing during “avascular sclerotic phase”
- edentulous patients require new dentures regularly
- unfavorable situation for osseointegration of implants
Fibrous Dysplasia is a fibro-osseous, tumor-like lesion of the jaw. Recent work suggests post-zygotic mutation of the tumor suppressor gene _______.
GNAS1
When does fibrous dysplasia present?
first or second decade
Does fibrous displasis have a sex predilection?
no
How often is Fibrous Dysplasia monostotic (one bone)?
70-85%
True or False: The jaws are among the most commonly affected bones of Fibrous Dysplasia.
True, maxilla> mandible
True or False: Fibrous Dysplasia is painless
True, slow-growing, painless unilateral swelling
What is a more severe presentation of Fibrous dysplasia?
Craniofacial Fibrous Dysplasia
-may involve facial bones including the sphenoid, zygoma, and occiput
What is the classic radiographic presentation of fibrous dysplasia?
“Ground Glass”
- irregularly shaped trabeculae of immature woven bone
- abnormal bone fuses to adjacent normal bone
- cellular intertrabecular connective tissue
True or False: Maxillary sinus obliteration is a common finding of fibrous dysplasia
True
Fibrous Dysplasia is commonly (70-85%) monostotic. What are the two polyostotic presentations?
- Jaffe Type
2. McCune Albright
Jaffe-Type Fibrous dysplasia includes two or more bones in conjunction with _______.
cafe-au-lait spots with jagged (coast of maine) borders
McCune-Albright type fibrous dysplasia includes two or more bones in conjunction with ______.
cafe-au-lait pigmentation endocrine disturbances (manifest as precocious "early" puberty)
What is the treatment for Fibrous Dysplasia?
en bloc resection for small lesions
surgical reduction for cosmetic
stabilization sometimes occurs with maturation
______ % of surgically treated Fibrous Dysplasia lesions show regrowth
25-50
True or False: Malignant transformation of fibrous dysplasia lesions is rare
True
Cemento-Osseous Dysplasias are _____, possibly reactive, processes that may originate from the _______.
benign
periodontal ligament fibroblasts
Cemento Osseous Dysplasia is most commonly seen in _____
african american females
then asian females, then white females
True or False: Cemento Osseous Dysplasias occur in tooth-bearing areas of the jaws and teeth are not vital.
False: yes tooth bearing areas are affected but the teeth test VITAL
What is the spectrum of severity for Cemento-Osseous Dysplasias?
Mild- Periapical
Moderate- Focal
Severe- Florid
Which area of the jaw is most commonly affected by cemento-osseous dysplasia?
anterior mandible
How does cemento-osseous dysplasia appear radiographically?
radiolucencies at apices with gradual central opacity developing (looks like it needs endo but the teeth are vital)
Differentiate between Cemento-osseous dysplasia and: hypercementosis, idiopathic osteosclerosis, cementoblastoma.
hypercementosis: radiodensity remains within the PDL
idiopathic osteosclerosis: not at apex, no lucent border
cementoblastoma: radiopaque mass around one root
True or False: No treatment is necessary for Periapical Cemento-Osseous Dysplasia.
True
Focal (moderate) Cemento-Osseous Dysplasia usually occurs in the _____ and has a _____ predilection.
mandible
female
Histological appearance of trabeculae in Focal Cemento-Osseous Dysplasia has a ______ appearance
ginger root
True or False: Treatment of Focal Cemento-osseous dysplasia is unnecessary.
True but biopsy is often warranted
What is the most severe presentation of Cemento-Osseous dysplasia? Which population group is most affected?
Florid
middle-age african american females
Florid-COD is generally asymptomatic but it affects _______ of the jaws.
multiple quadrants of the jaws
asymptomatic as long as there is no ulceration/sequestration
How does florid-COD appear radiographically?
cotton-wool radiopacities in multiple quads
true or false: biopsy is needed to diagnose florid-COD.
false, typical radiographic presentation
Lesions of florid-COD tend to be ______vascular and prone to _____ or secondary infection with minimal provocation.
hypovascular
necrosis
What is the treatment/management of cemento-osseous dysplasias?
regular recalls/OHI/prophylaxis
prevent tooth loss which could expose sclerotic mass
debridement/antibiotics if symptomatic
Development of ______ within an area of cemento-osseous dysplasia has been reported but is extremely rare.
sarcoma
