dysostosis

cleidocranial dysostosis an autosomal dominant condition in which there is defective ossification of the cranial bones, complete or partial absence of the clavicles, so that the shoulders may be brought together, or nearly together, in front, and dental and vertebral anomalies. See illustration.

craniofacial dysostosis an autosomal dominant condition marked by a pointed or conical skull, protruding wide-set eyes, strabismus, parrot-beaked nose, and hypoplastic maxilla with relative mandibular prognathism. Called also Crouzon's disease.

mandibulofacial dysostosis a hereditary disorder occurring in two different forms: the complete form is Franceschetti syndrome and the incomplete form is Treacher Collins syndrome. Persons with the condition have downslanting eyes (antimongoloid palpebral fissures); absence of all or part of the lower lid; underdeveloped cheekbones that appear depressed; a prominent nose, wide mouth, and small receding chin; underdeveloped, malformed, or prominent ears; and small tufts of hair in front of the ears. There is often, but not always, some degree of hearing loss, usually conductive.

metaphyseal dysostosis a skeletal abnormality in which the epiphyses are normal or nearly so, and the metaphyseal tissues are replaced by masses of cartilage, producing interference with endochondral bone formation and expansion and thinning of the metaphyseal cortices.

orodigitofacial dysostosis orofaciodigital syndrome.