Several bone diseases should be considered in the differential diagnosis of pycnodysostosis, most importantly cleidocranial
dysostosis, osteogenesis imperfecta and osteopetrosis.
Hypo-hyperdontia is rare in isolation and has been associated with over 50 syndromes, notably orodigitofacial dysostosis, Hallerman Streiff, cleidocranial
dysplasia syndrome, Ellis van Creveld, Down syndrome, cleft lip and palate, and many others [Zhu et al.
Olsen and his group came across Cbfa1 during a search for the genetic mutations that cause cleidocranial
dysplasia syndrome (CCD), a rare human skeletal disorder.
Dental development and molar root length in children with cleidocranial
dysplasia: a controlled study.
dysplasia is characterized by lack of normal development or absence of the clavicle bone, late ossification of cranial sutures, frontal and parietal bossing, shortness of stature and orodental abnormalities.
Multiple supernumerary teeth are usually associated with development disorders or syndromes such as cleidocranial
dysplasia or Gardner syndrome.