Ameloblasts and odontoblasts, target-cells for 1,25-dihydroxyvitamin D3: a review.

The basic features on the vitamin D endocrine system, synthesis of the main metabolite 1,25-dihydroxyvitamin D3 (1,25) and its genomic action mediated via the vitamin D receptor (VDR), are reviewed. Calbindin-D9k, calbindin-D28k and osteocalcin are presented as the most-extensively investigated vitamin D-dependent calcium-binding proteins. The action of 1,25 on the basic process of proliferation and differentiation is introduced. Then, the basis of the systemic theory of vitamin D action on teeth (clinical and experimental data and the dissimilar distribution of VDR and of potential vitamin D-dependent proteins in dental cells) are exposed. Finally, the data obtained with calbindin-D9k, calbindin-D28k, osteocalcin and VDR, which supports the theory that ameloblasts and odontoblasts are target-cells for 1,25 is presented. As a perspective, a cross-survey of the 1,25 and tooth-related literature is proposed which may indicate potential target-genes for 1,25 in teeth as done previously for calbindins-D.