Bone Dysplasia Flashcards
Jaffe’s type
Prenatal mutation after 1.5 m
Multiple bones are involved (most of skeleton is normall. Skin pigmentations in the form of Café au lait pigmentation with
irregular borders at trunk, thigh and rare in oral mucosa.
Etiology of fibrous dysplasia
Unknown Maybe 1- mutation in GNAS1 gene 2- infection 3. Gland Dysfunction
Albright syndrome
-most of body bones are affected
-cafe au lait stain on trunk thigh and rare in oral mucosa irregularly bordered (neurofibromatosis)
- endocrine problems
..DM
..hyperthyroidism
.. hyperparathyroidism
..hyper prolactinemia
.. precocious puberty pupic hair menstrual bleeding and breast development
Monostotic fibrous dysplasia clinically
The most common type (70-80 %% of cases).
- Only single bone is affected. 3. Site-> any bone may be affected as rib or limb or jaw [maxilla mandible).
- Signs & symptoms:
Slowly growing painless unilateral hard bony swelling → facial asymmetry. II. The enlargement is smooth (not nodular) and fusiform but more buccally than lingually.
In maxilla
Prominence of cheeks.
Buccal expansion distal to the canine may extend to tuberosity →→ obliteration of the canine fossa.
in extensive rapidly growing cases there may be marked swelling of cheeks & exophthalmos and proptosis due to displacement of orbital
content.
Teeth Failure of eruption.
In mandible)
In premalar & molar area (may be bilateral →→ mandibular prognathism).
Expansion of both buccal and lingual plates with bulging of the lower border of mandible and superior displacement finferior alveolar canal.
→ If teeth are crupted spacing and displacement & interfere with occlusion
Xray of fibrous dysplasia
The outline of lesion is often ill defined blending into adjacent normal bone (No line of demarcation () diseased and normal bone i.e. non capsulated).
In the 1” stage ill-defined radiolucent area.
In the 2nd stage →ill-defined mixed (mottled RL with RO).
+In the late stage →→ ill-defined radicopaque area (ground glass
or smoke screen & orange peel appearance).
a Roots of the teeth may be displaced & blending of lamina dura
with the abnormal bone.
o in maxilla the lesion may fill the maxillary sinus.
In craniofacial dysplasia → ↑ density of base of skull, sphenoid bone, frontal bone and roof of the orbit.
Ttt of fibrous dysplasia
-if small Complete surgical removal If large Surgery to decrease deformity May regrow No radiation therapy it may cause fubrosarcoma osteosarcoma or chondrosarcoma
Histology of fibrous dysplasia
Fibrous element
- fb in whorled pattern
- collagen fibers and bv
Multinucleated gc may be seen but not characteristic
- may be cellular with free collagen fibers
Or thick collagen bundles with few cells
Trabeculae Thin curvilinear Woven bone Chinese letter v w and c Blend at periphery with normal bone
Clinical of ossifying fibroma
Benign slowly growing lesion of the jaws.
C/P:
- Age3”-4” decades. older 2. Sex female predominance. Same
- Site mandible> maxilla. 4. Signs & symptoms:
تک
- Localized hard swelling of the jaw which is painless and non-tender.
- Slowly growing facial deformity.
ill. Displacement of the teeth may occur.
Histology of ossifying fibroma
H/P:
Well encapsulated lesion.
Collagenous stroma with various numbers of uniform spindle or stellate shape cells. Variable small ovoid to globular spherical calcification in the form of:
Irregular immature woven bone.
Lamellar bone.
+ Cementum like material.
Xray of ossifying fibroma
R/F:
o Varies according to the stage of lesions.
Early stage → well defined radiolucent area with no RO areas. Then → RL contain RO spots which ↑ until lesion appears as RO mass.
o Differentiation is dependent on the nature of delimitation of the lesion:
→ In fibrous dysplasia → more diffuse with ill-defined borders.
→in ossifying fibroma circumscribed, well defined borders.
Treatment surgical removal.
Jaw appearance in cherubism
- Site always involve mandible either alone or with maxilla & the 4 quadrants of jaws may be
involved.
o Maxilla lesions confined to maxillary tuberosity that may cause reduced or obliteration
of the palatal vault.
Mandible → posterior part involving mandibular angles and rami. 4. Painless, bilateral expansion of jaws with expansion of alveolar process. <
- Teeth→ Deciduous → irregularly spaced & premature loss.
→Permanent:
✓ May be absent due to no development of tooth germ.
✓May be imperfectly developed. ✓May remain unerupted or ectopic erupted.
✓May be widely separated in expanded bone.
Eye and lymph nodes in cherubism and course
Cherub or chubby or moon face: Characteristics fullness of checks and jaws.
Lymph nodes:
Marked enlargement of submandibular lymph node fullness of mandibular space.
The lymphadenopathy is reactive hyperplastic type that usually decreases after the age of 5
years & subsides completely during adolescence.
✓ Eyes:
The eyes show slight upturned appearance due to increase rim of sclera under iris due to deposition of ball & loss of support to lower eve lids & retraction of lower eve lid due to stretching skin over maxillary
bone on floor of orbit → upward displacement of eve
lesions).
1 Age & course2-4 years in size rapidly (4-7 years) → static phase or slowly progression (7 ys- puberty) → then growth until disappear (20 or 30 years) while the radiological appearance
Xray of cherubism
1 Bilateral, well defined, multilosarlar radiolucent area in posterior part of law (soap bubble or
honey combed appearance).
2 The unerupted teeth are often displaced and appear floating in the lesion.
Lab studies in cherubism
Laboratory investigation:
Normal serum calcium level.
Slight increase in serum alkaline phosphatase during period of rapid expansion.
Etiology of paget disease
May be
- autoimmune disease
- autonomic NS mediated vascular disorder
- chronic inflammation of the bone
- endocrine disease like hyperthyroidism
- viral infection
- inborn error of ct metabolism
