Abstract
Osteopetrosis represents a heterogeneous group of rare, hereditary bone dysplasias that share the hallmark of increased bone density caused by osteoclast dysfunction. It can manifest through a spectrum of symptoms and severity, from neonatal onset with life-threatening complications ("malignant" autosomal recessive osteopetrosis) to two more benign conditions with the incidental radiographic findings, principally affecting adults (autosomal dominant osteopetrosis type I and type II). We report 2 new cases of autosomal dominant osteopetrosis type II. Both subjects were short in stature. Multiple healed fractures of long bones, diminished marrow spaces and hypoplastic maxillary sinuses were remarkable findings. To our knowledge they are the first reported cases of autosomal dominant type II of this disease in Iran.