EFFECTS OF SERUM PHOSPHATE LEVEL ON FORMATION OF INCISOR DENTIN IN HYPOPHOSPHATEMIC MICE

The effects of serum phosphate level on the formation of incisor denti ne were investigated in hypophosphatemic (Hyp) mice fed a diet high in calcium and phosphorus (high Ca/P diet). Feeding a high Ca/P diet for more than 10 days resulted in an increase in the serum phosphate leve l in Hyp mice to one similar to that of normal mice. Lower incisors we re cut transversely at the centre of the length of the incisor, a poin t that had taken approximately 40 days to be reached from the start of dentine formation in Hyp mice. Transverse views of the incisors showe d a triangle-like outline in Hyp mice fed a control diet, while the ou tline became rounded in Hyp mice fed the high Ca/P diet for more than 40 days. In Hyp mice fed the high Ca/P diet for 40 days interglobular dentine was still observed and fluorescent lines produced by tetracycl ine showed a diffuse and wavy pattern in incisor dentine; however, int erglobular dentine became indistinct and fluorescent lines showed a re latively smooth pattern in the incisor dentine of Hyp mice fed the die t for more than 60 days.