Remineralization by fluoride enhanced with calcium and phosphate ingredients

The effectiveness of fluoride ions provided by toothpastes and mouthrinses in promoting remineralization can be limited by the low concentrations of c alcium and phosphate ions in saliva. The purpose of this study was to deter mine whether improved remineralization can be obtained from toothpastes or mouthrinses that simultaneously deliver fluoride, calcium, and phosphate io ns from dual-dispensing systems. Enamel specimens with artificial lesions b etween 60 and 90 microns deep were cycled 15 times through demineralization for 30 minutes, treated for 5 minutes with an experimental or control fluo ride toothpaste or mouthrinse, and remineralized for 60 minutes. In the too thpaste study, surface hardness increased by 11.5 +/- 9.2 and 2.7 +/- 3.6 V ickers hardness units, and enamel fluoride content was 5984 +/- 521 ppm and 3971 +/- 531 ppm for the experimental and control fluoride toothpastes, re spectively. Remineralization was confirmed by x-ray microradiography. In th e mouthrinse study, surface hardness increased by 8.8 +/- 7.7 and 2.2 +/- 3 .7 Vickers hardness units, and enamel fluoride content was 6111 +/- 1078 pp m and 3160 +/- 364 ppm for the experimental and control fluoride mouthrinse s, respectively. Use of a non-fluoride control mouthrinse led to a decrease in surface hardness of 3.7 +/- 5.2 Vickers hardness units despite a fluori de content of 402 ppm. The results demonstrate that calcium and phosphate s upplementation in a toothpaste or mouthrinse can improve remineralization a nd increase fluoride uptake.