Developmental Disorders
of the Bone
Osteogenesis Imperfecta
(Brittle bone Syndrome)
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It is hereditary disease of bone
Osteoporosis and Osteopetrosis
In osteporosis
Bones are fragile and brittle
It is often fatal if it develops during
intraurterine life.
• It may also develop during child hood
or early adult life.
Osteogenesis Imperfecta
(Brittle bone Syndrome)
• In osteoporosis the long bones are thin
with narrow poorly formed cortics
• Fractures are common but usually heal
without any trouble
• The skull is thin and tends to bulge
over the ear
• The jaws are severely affected
Osteogenesis Imperfecta
(Brittle bone Syndrome)
• They consists of small delicate trabeculae
• Cortices of the bone composed of immature
woven bone Osteoblasts fail to form bone in
adequate amount
• Other abnormalities are joint hypermobility
• Lax ligaments thin translucent skin, blue
sclerae
Osteogenesis Imperfecta
(Brittle bone Syndrome)
• The basic defect appears to lie in
collagenous matrix of the bone
• It is suggested that the disturbance of
normal cross-linking between collagen
molecules as collagen matures
• It is inherited as an autosomal dominont
• It is often associated with dentinogenesis
imperfecta
Osteopetrosis (Albers – Schoenberg
or Marble Bone Disease)
• It is characterized by excessive density
of bones
• Obliteration of marrow cavities
• Development of secondary anemia
• Defect in Osteoclastic activity
• Failure in remodeling of developing
bone
Osteopetrosis (Albers – Schoenberg
or Marble Bone Disease)
• There is an excessive bone formation
which is mechanically weak so the
fractures are common
• Delayed eruption of teeth
• Osteomyelitis is common complication
of tooth extraction
Osteopetrosis (Albers – Schoenberg
or Marble Bone Disease)
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There are two types:
a) Malignant and prograsive inherited as
autosomal recssive and occur early in
life with severe bone fragility
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Death usually occurs before buberty
Osteopetrosis (Albers – Schoenberg
or Marble Bone Disease)
b) A benign autosomal dominant type
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Bone charges are less severe
There may be repeated fracture following
minor trauma
Osteopetrosis (Albers – Schoenberg
or Marble Bone Disease)
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RADIOLOGY shows increase density
of bone in all skeleton with no
distinction between cartical and
madullary bone
Base of the skull shows marked
radiopacity where as the vault is
generally less dense
Osteopetrosis (Albers – Schoenberg
or Marble Bone Disease)
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RADIOLOGY
Mandible is more frequently affect
than maxilla
Density of the bone reaches to the
roots of the teeth so roots are
invisible on X-Ray
Cleidocranial Dysostosis
(Cleidocranial Dysplasia)
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The disease is transmitted as an
autosomal dominant trait
It is characterized by abnormalities of
many bones
The disease is particularly of the
skull, Jaws Clavicle and dental
abnormalities
Cleidocranial Dysostosis
(Cleidocranial Dysplasia)
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In the skull the fontanelles and
sutures tends to remain open
Skull appears flat with prominent
frontal paratal and occipital bones
Partial or complete absence of
clavicles allows the shoulders to be
brought forwards until they meet in
midline
Cleidocranial Dysostosis
(Cleidocranial Dysplasia)
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The maxilla may be under developed with
high narrow arched palate
Deciduous dentition tends to retain with
delayed or non eruption of permanent
dentition
Multiple impactions and supernumerary
teeth are common specially in a mandibular
premolar and incisor region
The roots of teeth are thinner than normal