1087 Changes in the Salivary Fluoride Concentration after Adding Low-concentrated Fluoride

Friday, March 23, 2012: 3:30 p.m. - 4:45 p.m.
Presentation Type: Poster Session
T. IWASAKI, Pediatric Dentistry, Nippn Dental University Hospital, Tokyo, Japan, and Y. UCHIKAWA, Pediatric Dentistry, Nippon Dental University Hospital, Tokyo, Japan

The aim of this study was to investigate the changes in the fluoride (F) concentration in saliva after adding low-concentrated F, and to determine the influence of protein (mucin and albumin) and calcium in the saliva on the concentration of low level F.


A flow injection analysis (FIA) instrument was used to determine the F ion concentrations in saliva. FIA can determine the F in a sample solution at a concentration as low as 0.005 ppm (5μg/L). A standardized solution (0.01, 0.05, 0.5ppm F) was added to the saliva at a rate of 1:9, and then the temporal changes in the F ionic level were measured. The change in the F concentration after the addition of F was determined as the increase in the F concentration from the original salivary F concentration. Similarly, F standard solution (0.5ppm) was added to a protein solution (mucin or albumin, 3%) and a calcium solution (1.25mg/100ml), and then the changes in the F concentration were again examined. Both ANOVA and t-tests were used to compare the F concentrations.


The F ion concentration in the saliva that contained the additional F showed a decrease of 17-45% in comparison to the F ion concentration of purified water that contained F.  When F was added to mucin, albumin and calcium, there were 18.6, 15.7, and 34.6% reductions in the concentration, respectively. In addition, the concentration of F in mucin+ calcium and albumin+calcium was found to have decreased by 62.1 and 44.8%, respectively.


The mixture with a solution of calcium and protein led to a higher rate of decline in the F concentration than the sum of the decline rate of each solution independently. These results suggested that there is a synergistic effect of protein and calcium on the low F concentration in saliva.

Keywords: Cariology, Fluoride, Human, Proteins and Saliva