DWARFISM(ACHONDROPLASIA)

ACHONDROPLASIA

Literally means “without cartilage formation”

Most common type of dwarfism.

Caused by mutation of gene for (FGFR3)

Average height is about 4 ft.

Short arms and legs.

Large head.

Achondroplasia is one of a group of disorders

called chondrodystrophies or

osteochondrodysplasias.

May be inherited as an autosomal dominant trait,

which means that if a child gets the defective gene

from one parent, the child will have the disorder.

SIGNS AND SYMPTOMS

Abnormal hand appearance with persistent space

between the long and ring fingers

Bowed legs

Decreased muscle tone

Disproportionately large head-to-body size

difference

Prominent forehead

Shortened arms and legs (especially the upper arm

and thigh)

Short stature (significantly below the average

height for a person of the same age and sex)

Spinal stenosis

Spine curvatures called kyphosis and lordosis

DENTAL CORRELATION

The administration of thyroid hormone is known to

accelerate dental development and eruption

His dental development is still extremely retarded

and is following a disturbed pattern in which

various stages of dental development are present

simultaneously

SINGLE GENE

It is considered as single gene because only the

Fibroblast Growth Factor Receptor Gene 3 is

affected which is also important in the maintenance

of bone and brain tissues