[The pycnodysostosis (author's transl)].

Two own observations of pycnodysostosis initiated our description of this disease. Inherited as an autosomal recessive trait the syndrome is characterized by a medium degree generalized osteosclerosis, open craniial sutures and fontanels until adult lige, hypoplastic mandibles with deficiency of the angle, prominence of the forehead and occiput, hypoplasia of the paranasal sinuses, commonly observed dysproportionate dwarfism, acro-osteolysis and increased bone fragility. Contrary to osteopetrosis the prognosis is good.