Increased Overnight Fluoride Concentrations in Saliva, Plaque, and Plaque Fluid after a Novel Two-solution Rinse

Abstract

Recent studies showed that salivary, plaque-fluid, and whole-plaque fluoride were significantly higher 120 min after subjects rinsed with a novel two-solution rinse than after they rinsed with a NaF rinse of the same fluoride concentration. In this study, the persistence of these increases was investigated overnight, a period of time that is more clinically relevant. Improved analytical techniques for the ultramicro determination of whole-plaque and plaque-fluid fluoride from the same sample are also described. Thirteen subjects abstained from toothbrushing for 48 hrs and rinsed for 1 min with a 12 mmol/L (228 ppm) NaF or the two-solution rinse before bedtime. Samples were then collected the following morning before breakfast: (1) Saliva samples were either clarified by centrifugation or acid-extracted with 1 mol/L HClO4; and (2) single-site molar plaque samples were centrifuged to obtain plaque fluid and/or extracted with 1 mol/L HClO4. Results showed that, compared with NaF, the two-solution rinse produced significantly higher fluoride concentrations in all samples: The concentration of fluoride in whole plaque and whole saliva following the new rinse exceeded concentrations found after the NaF rinse by factors of three and four, respectively, while in plaque fluid, the two-solution rinse produced about a two-fold increase over NaF values, which were near baseline levels. This increase, however, was only about 20% in centrifuged saliva. The increases in saliva and especially in plaque-fluid fluoride after the two-solution rinse indicate a greater remineralization potential, while the enhanced fluoride reservoirs found in plaque overnight after this rinse constitute a reserve that may release fluoride into the plaque fluid over an extended period of time.

How to Improve Oral Fluoride Retention?

“…The content of this table is dynamic and will change due to new results from constantly ongoing research on the fluoride retention of various products. Vogel et al [1997] and Takagi et al [1997] presented data supporting the theory that the retention of fluoride increases following the administration of so-called twosolution fluoride rinses, in which various fluoride salts interact to increase retention compared with the situation if only one salt is present. A combination of many more substances is also possible.…”

Antimicrobial Activity of Fluoride and Its in vivo Importance: Identification of Research Questions

“…Furthermore, it is of interest to study whether the uptake of fluoride by cells can be enhanced at physiologic pH of dental plaque [Marsh et al, 1985], whether the substantivity of fluoride in dental plaque can be increased [Vogel et al, 1997] and whether additives like benzoate and sodium bicarbonate can enforce the efficacy of fluoride.…”

Changes in Lactate and Other Ions in Plaque and Saliva after a Fluoride Rinse and Subsequent Sucrose Administration

“…4 All saliva fluoride rinse values from one subject were statistical outliers using the criteria previously described [Vogel et al, 1997] and were omitted. The values were at times 0, 7, 15 min, 325, 187, and 132 ÌM, respectively. recruited to participate in the study.…”

“…The plaque collection and sample preparation have been extensively described [Vogel et al, , 1997 and are only summarized here: (1) collection of about 1 mg of plaque with plastic strips, (2) determination of the plaque mass under mineral oil to prevent evaporation and loss of CO 2 , (3) centrifugation to separate plaque fluid and whole plaque residue, (4) recovery of plaque fluid (approximately 0.1 Ìl) with mineral oil-filled micropipettes, and (5) extraction of the remaining plaque mass with 1 M perchloric acid. A weighed 1-min saliva sample was collected immediately following the plaque samplings by expectoration, without prior swallowing, as previously described [Vogel et al, 1998].…”

“…The analysis procedures are very similar to those previously employed and are only summarized [Vogel et al, , 1997[Vogel et al, , 2001. Plaque fluid or centrifuged saliva samples were analyzed for free calcium and pH using microelectrodes.…”