Affiliation: | (1) Mineral Metabolism Research Unit, University of the Witwatersrand, Johannesburg, South Africa;(2) Dental Research Institute of the Medical Research Council of South Africa, University of the Witwatersrand, Johannesburg, South Africa;(3) Department of Orthopaedic Surgery, University of the Witwatersrand, Johannesburg, South Africa;(4) Medical School, 7 York Road, 2193 Parkton, South Africa |