There is evidence that a derangement in vitamin D metabolism on the part of the mother, the fetus, or both may be responsible for supravalvular aortic stenosis, especially when the latter is associated with infantile hypercalcemia. It has been shown that the offspring of rabbits given large amounts of parenteral vitamin D throughout pregnancy may be born with aortic lesions resembling supravalvular aortic stenosis as seen in man. The present study was designed to explore experimentally the relationship between exposure to excessive amounts of vitamin D during pregnancy and the development of the craniofacial complex and dentition because children with the multiple system abnormalities of the supravalvular aortic stenosis syndrome (SASS) share a characteristic craniofacial appearance and exhibit, in common, many abnormalities of dentition. Examination of their jaws and teeth reveals hypoplasia of the mandible, congenital absence of teeth (usually the lateral incisors and second premolars of the maxilla), microdontia, dysgnathia, enamel hypoplasia, and a narrowed occlusal table. In the present study, analogous findings were observed in rabbit offspring whose mothers received large amounts of vitamin D during pregnancy. The most marked functional accompaniment of these abnormalities was severe malocclusion of the teeth. Peculiar facies, premature closure of the cranial bones, strabismus, odd shaped ears, and a low birth weight were additional features of SASS that were noted in many test animals. Buphthalmos was also noted occasionally, probably related to maldevelopment of the bony ocular orbits. Thus, these experimental observations suggest that the cranial, facial, and dental peculiarities as well as the aortic lesion of the supravalvular aortic stenosis syndrome may be related to a derangement in vitamin D metabolism during pregnancy.
Novel
ELN
mutation in a Japanese family with a severe form of supravalvular aortic stenosis