Is osteogenesis imperfecta a form of dwarfism?

Not true dwarfism: Osteogenesis imperfecta is a genetic disorder in which a person has a mutation in his dna that causes him to have defective connective tissues and/or smaller amounts of connective tissue. His bones are weakened and brittle, so they break more easily. In the severe forms, the bones break so often, from infancy, so that one ends up small. One's shortness is due to multiple fractures.

Yes : In it's more severe stated there is retardation of growth therefore dwarfism would be seen.