A condition that primarily affects the development of the bones and teeth. Characteristic features include underdeveloped or absent collarbones (clavicles); dental abnormalities; and delayed closing of the spaces between the skull bones (fontanels). Other features may include decreased bone density (osteopenia), osteoporosis, hearing loss, bone abnormalities of the hands, and recurrent sinus and ear infections. CCD is caused by changes (mutations) in the RUNX2 gene and inheritance is autosomal dominant. It may be inherited from an affected parent or occur due to a new mutation in the RUNX2 gene. Management may include dental procedures, treatment of sinus and ear infections, use of helmets for high-risk activities, and/or surgery for skeletal problems. The disease is cleidocranial dysplasia 1 (MONDO_0007340). Also known as: Cleidocranial Dysplasia, Marie-Sainton disease, cleidocranial dysostosis, cleidocranial dysplasia.