Types

The four types are as follows:

• I mild disease
  • blue sclerae
  • mild prepubertal bone fragility
  • little or no deformity
  • mild short stature
  • hearing loss in about 50% of adults
  • dentinogenesis imperfecta may be absent (IA) or present (IB)
  • bruises easily
• II perinatal lethal
  • blue sclerae
  • in utero fractures
  • micromelia
  • marked long bone deformity
  • platyspondyly
  • lethal in the perinatal period
  • broad but poorly mineralized skull
• III progressive deforming
  • blue then white sclerae
  • progressing deforming of the long bones and spine secondary to fractures and gravity
  • relative macrocephaly and triangular faces
  • extremely short stature
• IV moderately severe disease
  • white sclerae
  • moderate fragility and mild to moderate bowing of long bones
  • variable short stature
  • dentinogenesis imperfecta absent (IVA) or present (IVB)