BONE DISEASES Dr. Ahmed M. Attay - PowerPoint Presentation

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BONE DISEASES

Dr. Ahmed M. Attay

Slide2

Classification of bone diseases

It is not easy to classify bone diseases, since many of them are of unknown etiology or

their nature

is poorly understood

.

Hereditary

1.

Cheurbism

(fibro-osseous lesion).

2.

Osteogenesis

imperfect

(brittle bone disease;

fragitalis

ossium

)

3.

Osteopetrosis

(marble bone disease, Albers

schonberg

disease).

4.

Cleidocranial dysplasia

(affecting mainly membrane-formed bones).

5.

Achondroplasia

(affecting bones formed by cartilage).

Developmental

Fibrous dysplasia of bone

(

fibro-osseous

lesion).

Slide3

Classification of bone diseases

Reactive

1.

Cemento-osseous dysplasias

(fibro-osseous lesions):

a. Periapical cemento-osseous dysplasia.

b. Florid cemento-osseous dysplasia (gigantiform cementoma).

c. Focal cement-osseous dysplasia.

2.

Cemento-ossifying fibroma

.

3.

Juvenile ossifying fibroma

.

4.

Central giant cell granuloma

.

Dystrophic

Paget’s

disease of bone

(osteitis deformans

).

Slide4

Classification of bone diseases

Hormonal

1.

Hyperparathyrodism

.

2.

Gigantism and acromegaly

.

3.

Osteoporosis

.

Nutritional

and metabolic

1.

Vitamin C deficiency

(scurvy).

2.

Vitamin D deficiency

.

3

. Hypophosphatasia

.

4.

Fluorosis

.

Slide5

Classification of bone diseases

Idiopathic

Skeletal

reticulonedotheliosis

.

1.

Non-lipid

histiocytoses

(

Langerhan’s

cell disease

):

a

. Eosinophilic granuloma.

b

. Hand-

Schüllar

-Christian disease.

c

. Letterer-

Siwe

disease.

2.

Lipid

reticuloendotheliosis

:

a

.

Gaucher’s

disease.

b

.

Niemann

-Pick

disease.

Slide6

Classification of bone diseases

Inflammatory

1.

Osteomyelitis:

a

. Non-specific inflammatory lesions:

i

. Suppurative.

ii

. Sclerosing.

b

. Specific inflammatory lesions:

i

. Chemical and irradiation necrosis.

ii

. Infectious types: tuberculous, syphilitic and

actinomycotic

osteomyelitis.

2.

Dry

socket, Dento-alveolar

abscess, periapical granuloma

.

Slide7

Classification of bone diseases

Cystic

1.

True cystic lesions:

a

. Odontogenic cysts.

b

. Non-odontogenic cysts.

2

.

Pseudocystic

lesions:

a

. Traumatic bone cyst.

b

. Aneurysmal bone

cyst.

Slide8

Classification of bone diseases

Neoplastic

Benign

tumors

:

1.

Benign odontogenic tumors:

ameloblastoma and others.

2.

Benign non-odontogenic:

a

. Osteoma.

b

. Osteoid osteoma and osteoblastoma.

c

. Chondroma.

Slide9

Classification of bone diseases

Neoplastic

B. Malignant tumors

:

1

. Malignant odontogenic tumors:

a

. Ameloblastic carcinoma / malignant ameloblastoma.

b

. Ameloblastic fibrosarcoma.

2.

Malignant non-

odotnogenic

tumors:

a

. Osteosarcoma / Chondrosarcoma.

b

. Fibrosarcoma.

c

. Intra-osseous mucoepidermoid carcinoma.

Slide10

Classification of bone diseases

Neoplastic

B. Malignant tumors

:

3.

Malignant myelogenic tumors:

a

. Plasma cell myeloma and multiple myeloma.

b

. Ewing’s sarcoma.

c

. Reticular cell sarcoma.

4.

Metastatic tumors

:

a

. Carcinoma of the lung (bronchogenic carcinoma).

b

. Carcinoma of the thyroid gland.

c

. Carcinoma of the stomach.

d

. Carcinoma of the prostate.

e

. Carcinoma of the kidney (

hypernephroma

).

Slide11

Hereditary

bone diseases

Slide12

Hereditary bone diseases

Cherubism (Familial fibrous dysplasia

)

A

familial

intra-osseous fibrous swelling

of the jaws.

An

autosomal

dominant pattern

of inheritance in this condition.

In

some cases

no family history

is obtained

and these

may be due

to

spontaneous

mutations

.

Clinical features:Not permanent, it is a self-limiting condition.It affects children and infants between the first year and 10-12 years of age.No pain, disfigurement is the only symptom.Developing teeth are often displaced and fail to erupt.Impaired mastication and speech difficulties.

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Hereditary bone diseases

Cherubism (Familial fibrous dysplasia

)

Clinical

features

:

In

the

mandible:

it

shows painless,

bilateral expansion of posterior mandible

(early

manifestation).

Then

spread to involve the mandibular angle or ramus giving the

characteristic

chubby face

(as in plump-cheeked little angels) and the expansion is equal

bilaterally.

In the maxilla: when it is involved the lesion is usually limited to the tuberosity. In somecases extensive maxillary involvement causes stretching of the skin of upper face andexposes the sclera. This result in an eye upturned to heaven appearance.Enlargement of submandibular and cervical lymph nodes is evident and that usuallysubsides with adolescence.

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Hereditary bone diseases

Cherubism (Familial fibrous dysplasia

)

Radiographic features:

Sharply

defined

multilocular radiolucent areas

(bilaterally which is diagnostic).

Numerous

unerupted and displaced teeth

are seen.

Expansion

of bone and thinned cortex

with time new cortical bone is laid down.

Sometimes

lesion may be

unilateral and unilocular

and should be differentiated

from dentigerous

cyst as it may include a

root.

Laboratory investigations:Increase alkaline phosphatase enzyme level. Normal blood and urine biochemistry.

Slide15

Hereditary bone diseases

Cherubism (Familial fibrous dysplasia

)

Histological features:

Normal

bone has been replaced by

vascular loosely arranged

fibrous tissue

.

This

fibrous tissue

multinucleated giant cells

can be seen either around

thin walled

vessels or lie within the vascular

spaces

.

Areas

of

hemorrhage and hemosiderin deposition

are usually seen.

In older resolving lesions, the tissue becomes more fibrous and the number of giant cells decreases, with new bone formation. Histological features of cherubism are not diagnostic in the absence of clinical and radiologic information.

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Hereditary bone diseases

Cherubism (Familial fibrous dysplasia)

Treatment and prognosis:

Unpredictable

prognosis but

generally may show remission as it is self-limiting

condition especially

with puberty

due to remodeling of bone.

However

,

facial deformity may

persist in

some cases

.

Radiation

is contraindicated

to avoid the development of post-irradiation osteosarcoma.

Early

surgical interference

with curettage of the lesion may of value in some cases but

in other cases may be followed by rapid regrowth of the lesion.Curettage is done in periods of remission because the lesion during involution is highly vascular and hemorrhage can occur.Surgical removal is completely contraindicated because it will lead to severe bone deformity with bad prognosis.

Slide17

Hereditary bone diseases

Osteogenesis imperfecta

(

Brittle bone disease;

Fragitalis

Ossium

)

The

most common inherited

bone disease

.

Heterogeneous

group

characterized

by

impairment of collagen maturation

.

It

is transmitted as an

autosomal dominant trait

.It results in a mutating defect of osteoblasts and defect of the biosynthesis of bone matrix(maturation type I collagen) which leads to deficiency in ossification.The basic defect is in collagen I formation as collagen forms a major portion of bone, dentin, sclera, ligaments and skin.There are four subtypes according to the severity of the defect that affects the osteoblast.The formed cortical bone is thin and the cancellous bone has fine widely separated trabeculae with large medullary spaces.

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Hereditary bone diseases

Osteogenesis imperfecta

Clinical features:

The

bone is fragile and osteoporotic

where it has high tendency to

fracture

even

during

delivery

; this is due to

defect in skeleton ossification

. At the site of fractures there

would be

angulation deformity

.

In

severe congenital type there are

multiple fractures in utero and infants seldom survive

.

Hyper-laxity of the ligaments of hands, feet and knees is common in children. The skull has a peculiar shape because of defects in the cranial vault ossification. Blue sclera is evident because it is thin thus exposing pigments of the choroids. Hearing impairments and heart valve defects are also evident. Long bone and spine defects.

Slide19

Hereditary bone diseases

Osteogenesis imperfecta

Oral cavity findings:

Both

dentitions are involved

. They show blue to brown translucency (

opalescent teeth

).

The involved teeth resemble

dentinogenesis imperfect

, the two

diseases are the result of different mutations and should be considered

as separate

processes.

Slide20

Hereditary bone diseases

Osteogenesis imperfecta

Histological features:

Osteoblasts are present but

bone matrix production is reduced

markedly.

Dissolution

of both medullary and cortical bone

.

The

connective tissue contains many

dilated capillaries

with thin trabeculae of

woven bone

.

Bone

architecture remains immature

throughout life to be transformed into lamellar bone

.

Slide21

Hereditary bone diseases

Osteopetrosis

(

Marble bone disease; Albers-Schonberg disease)

Rare

hereditary bone disorder characterized by

increase in bone density due to defect

in bone

remodeling

caused by

failure of normal osteoclast function

.

There

are two clinical types the

infantile and the adult

osteopetrosis.

Pathogenesis:

The

imbalance between osteoblastic and osteoclastic activity

leads to

increased

bone density throughout the skeleton on the expense of medullary spaces and so bone become brittle and fractures are more easily.In osteopetrosis, osteoclasts fail to function normally. As a result, bone remodeling is affected and a defective bone resorption combined with continued bone deposition results in thickening of cortical bone and sclerosis of cancellous bone.

Slide22

Hereditary bone diseases

Osteopetrosis

Clinical

features:

Pain

and frequent fractures

especially of the long bones which often do not heal.

Hematologic

disturbances include anemia, thrombocytopenia, leucopenia

and bleeding.

Enlarged

liver and spleen

, with increased tendency to infections and thoracic scoliosis

.

Oral manifestations:

Facial deformity leading to

hypertelorism, snub nose and frontal bossing

.

Sclerosis of skull bones leads

to narrowing of foramina which causes compression of various cranial nerves, leading to blindness, deafness and facial paralysis.Pain, osteomyelitis of jaws and delayed tooth eruption are common to occur.

Slide23

Hereditary bone diseases

Osteopetrosis

Radiographic features:

Widespread

radiopacities

of the affected bone

due to increase in bone density.

No

distinction between bone cortex and cancellous bone

.

Transverse

bands of

varying density producing a zebra like effect

which may be seen.

In

dental x-ray,

roots cannot be distinguished

.

Histological features:

Thick

lamellar bone, cortex, trabecula.

Small marrow spaces.Bone inflammation (osteomyelitis).

Slide24

Hereditary bone diseases

Cleidocranial dysplasia

Inherited bone disease

which is transmitted as autosomal dominant trait.

It affects

cranium skull, shoulder girdle

and also has

oral manifestations

.

Clinical features:

Skull manifestation:

Flat skull with short head

due to delayed closure of the fontanels and sutures. They may remain open throughout the patient's life (on skull radiograph).

Also, there are

sunken sagittal sutures, hypoplastic facial bones and underdeveloped nasal sinuses

.

Shoulder girdle manifestation:

Absence or hypoplastic clavicle

leading to long neck and dropped narrow shoulder.

Other features:

Short

body stature with large head and pronounced frontal and parietal bones.Depressed nasal bridge or cleft palate, as well as ocular hypertelorism.

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Hereditary bone diseases

Cleidocranial dysplasia

Oral manifestations:

Hypoplastic

maxilla with high palatal arch

and open bite.

Prognathic

mandible.

Prolonged

retention of deciduous teeth and delayed eruption

of permanent teeth.

Numerous

unerupted supernumerary teeth

, with partial anodontia as a result

of overcrowding

of teeth germs

.

Absence

of cellular cementum

on the root of permanent and deciduous teeth.

Roots are short, hooked, curved and thinner than normal.Crowns are conical in shape with pitted enamel.Increase prevalence of cleft palate.Multiple dentigerous cysts.

Slide26

Hereditary bone diseases

Achondroplasia

It is a

genetic inherited condition

that results in abnormally short stature due to

abnormal endochondral

ossification

in the epiphysis and bone of the skull while

the intramembranous

ossification is not affected.

It

is

inherited by an autosomal dominant gene

that causes abnormal cartilage formation.

It

is the most common type of

dwarfism in which the child’s arms and legs

are disproportionately

short

in relation to body length.

All

persons with achondroplasia are small people.Pathogenesis:The skeleton of human fetus is composed primarily of cartilage that gradually turns to bone during normal development.In achondroplasia, a gene that is involved in the process of bone formation produces too much of protein that limits bone growth.

Slide27

Hereditary bone diseases

Achondroplasia

Clinical features

:

Short

bones in the arms, legs and other

skeletal abnormalities

.

They

usually have

difficulties in posture, joint disorders and breathing problems

.

Large

head

with prominent forehead and flattened nasal bridge.

Normal

trunk size, while the feet are flat, short and broad

.

Average

height of an

adult male

is about 130 cm, while the average height of an adult female is about 128 cm.Curved lower spine, condition called lordosis, which may lead to kyphosis.Crowded teeth with malocclusion.Retruded middle third of the face, due to the defective growth of the base of the skull.

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