BONE DISEASES
BONEone of the hardest tissues of body Ch. Ch. By high elasticity
Bone is a calcified collagenous matrix with some cells entrapped in-between
TYPES OF BONE3 types have been recognized
1- Lamellar bone = Mature bone
2- NON-Lamellar bone = Immature bone = WOVEN BONE
3- Bundle bone
Classification of bone diseases
HORMONALBONE DISEASES
= Osteitis Fibrosa Cystica = Von Recklinghausen's disease of bone
Hyperparathyrodism
= PTH
?In 2ry hyperparathyroidism, high levels of PTH do not cause hypocalcaemia
2 Types (1ry, 2ry hyperparathyroidism) are harmful to bone????!!!
Clinical features
DevelopmentalBONE DISEASES
Fibrous Dysplasia of boneBone is replaced by Fibrous C.T
Fibrous Dysplasia of boneFibrous Dysplasia of boneFibrous Dysplasia of boneBone is replaced by Fibrous C.T
proliferating gritty
Bone resorption Fibrous replacement Ossous metaplasiaWoven Bone
Fibrous Dysplasia of boneEtiology ??!!
1. Non- Neoplastic growth2. Abnormal reaction to traumatic episode.3. Endocrinal disturbances.
TYPES
Monostotic Fibrous Dysplasia= fibrous dysplasia confined to a single bone, 6 times as polyostotic
Age 1st or 2nd decade of life (4-18 years) Sex ♀ = ♂
Siteaffects only one bone particularly the jaws.Max. > Mand.
S&S
Slowly growing painless swelling…. not well circumscribed (diffuse)smooth and covered e normal mucosa.Disfiguring
stabilization and expansion stops with skeletal maturation.
Age 1st or 2nd decade of life (4-18 years) Sex ♀ = ♂Site affects only one bone particularly the jaws.
Max. > Mand.
S&S
Slowly growing painless swelling…. not well circumscribed (diffuse)smooth and covered e normal mucosa.Disfiguring
stabilization and expansion stops with skeletal maturation.
Polystotic Fibrous Dysplasia =fibrous dysplasia involve multiple bones, up to 75% of skeleton
Age 1st or 2nd decadeSex ♀>♂Site involves several bones including long bones, skull and jaws.
S&S
Slowly growing painless swelling…. not well circumscribed (diffuse)smooth and covered e normal mucosa.Disfiguring
stabilization and expansion stops with skeletal maturation.
Jaffe 's syndrome Albright’s syndrome
Polystotic fibrous dysplaisa
Café au lait skin pigmentation
Endocrinal disturbances
Polystotic fibrous dysplaisa
Café au lait skin pigmentation
Oral manifestation
Radiographic features
1. Mottled or Mixed
2. Radio-opaque.
Lesions merge with normal bone at the margins (= ill defined)
Lesion differ radiographoically according degree of osseous metaplasia
Histopathological features
Treatment
Self limiting
Cosmotic surgery may be needed
DystrophicBONE DISEASES
Paget’s disease of bonePaget’s disease of bone2nd most common osteodystrophic condition after osteopetrosis
1. Inflammatory disease (Paget's original believe).2. Autoimmune disease.3. Endocrine abnormality related to hyperthyroid
disease.4. vascular disorder.5. Bone remodling disturbance.6. viral infection (paramyxo v. + measles + RSV)
Etiology ??!!Phases
Age uncommon before age 40 (= 40 years)
Sex ♂> (2:1)♀
Site
vertebral column (1st most common site) - Sacrum > Lumbar > Thoracic > Cervical vertebrae. - mechanical stress i.e bearing most wt. being most affectedSkull (next most frequently affected) - mand. & max. about 17% of cases. - Max.> Mand. - functional stress + traction of neck muscles + stresses of mastication
S&S
severe pain.Bones become larger…. flat bones become thicker. round bones in circumference hats and dentures may no longer fit. Weight bearing bones…… bend under pressure crippling + bowing deformities. break easily.Deafness and Blindness , d.t. narrowing of cranial foramina.High cardiac output failure may occur due to arteriovenous shunt.
Clinical features
Clinical features
Clinical features
Clinical features
Clinical features
Clinical features
Radiographical features
Histopathological features
HereditaryBONE DISEASES
A) Affects membranous bone
B) Affects endochondral bone
C) Affects both types of bone
OI , cherubism , osteopetrosis
achondroplasia
Cleido-cranial dysplasia
Cherubism= familial fibrous dysplasia = familial multilocular cystic disease of jaws
Age early childhood bn (2-4 years)Sex ♂ > ♀Site Mand.> Max.
S&SBilateral ,Firm, painless swelling at angles of mand.
Clinical features
Pathogenesis