HLA antigens in South African Afrikaners with heterozygous familial hypercholesterolaemia.

normal pulp cavities exclude dentinogenesis imperfecta". In the dentine abnormalities that may be associated with osteogenesis imperfecta, the pulp chambers and root canals are either progessively obliterated by the continuous deposition of highly disorganised dentine, or the pulp chambers are larger than normal by a failure of deposition. It is not possible to ascertain whether or not the pulp chambers are in fact enlarged, or to measure the amount of obliteration without taking periapical radiographs and comparing them with age matched controls. There is also no mention in the article about tooth crown morphology or if, in fact, the teeth are smaller with cusp tips closer together than normal. Nor is there any reference to the presence or absence of short tapering roots. Although discoloration and opalescence are the more easily observed signs of abnormality, they are not the only criteria for the classification of dentinogenesis imperfecta.