Types:
The fagility of the bones differs from patient to patient so the number of fractures varies from few to 100. Joint tissue is also affected, as well the bone tissue. Apart from the fractures the following symptoms aslo apply:

Type Ι

This is the most common and mildest type in which the common features are the following:

• Bones are predisposed to fracture, with most fractures occurring before puberty with the number of fractures not being bigger than 20 – 40 fractures.

• Stature is normal or near – normal.

• Joints are loose and muscle tone is low.

• Usually sclera (whites of the eyes) have blue, purple or gray tint.

• Face shape is triangular.

• Tendency toward scoliosis (a curvature of the spine).

• Bone deformity is absent or minimal

• Dentinogenesis imperfecta may occur, causing brittle teeth.

• Hearing loss is a possible symptom, often beginning in early 20s or 30s.

• Structure of collagen is normal, but the amount is less than normal.

Type ΙΙ

This type is the most severe form of O.I. The common features of it are the following:

• O.I. Type II is lethal shortly after birth, often as a result of respiratory problems.

• Fractures are numerous and bone deformity is severe

• Stature is small with undeveloped lungs.

• Collagen is formed improperly.

• In recent years people with osteogenesis imperfecta type 2 have reached their early adult years.

Type ΙΙΙ

Common symptoms are:

• Bones fracture easily and people with O.I. Type III may have more than 100 fractures before puberty. Fractures are often present at birth, and x rays may reveal healed fractures that occurred before birth.

• Stature is significantly shorter than normal.

• Usually sclera (whites of the eyes) have blue, purple or gray tint.

• Face shape is triangular.

• Scoliosis (a curvature of the spine) is present..

• Joints are loose and muscle development is poor in arms and legs.

• Rib cage is barrel – shaped.

• Respiratory problems are possible.

• Bone deformity is often severe.

• Dentinogenesis imperfecta may occur, causing brittle teeth.

• Hearing loss is possible

Type ΙV

This Type falls between Type I and Type III in severity. Among the common features of it are the following:

• Bones fracture easily, with most fractures occurring before puberty.

• Stature is shorter than average.

• Sclera (whites of the eyes) is normal in color, appearing white or near – white.

• Bone deformity is mild to moderate.

• Scoliosis (curvature of the spine) is likely.

• Rib cage is barrel- shaped.

• Face is triangular in shape.

• Dentinogenesis imperfecta may occur, causing brittle teeth.

• Hearing loss is possible

• Collagen is formed improperly.