Abstract:
The objectives were to determine 1) fluoride releasing level of an experimental
formula-2 (ExF2) fluoride varnish developed by Faculty of Dentistry, Mahidol
University in artificial saliva, 2) plaque and salivary fluoride levels after ExF2
application and compare with imported products.
One hundred and twenty enamel slabs from human bicuspids were randomly
divided into a control and 5 experimental groups. They were painted with 3.67 mg of
ExF2, Fluorilaq®, Duraphat®, Fluoridin N5®, Flor-Opal® and immersed in artificial
saliva at 37 oC. The fluoride concentration (ppm) was measured daily for the first 15
days and then weekly until 2 months. Kruskal-Wallis test and Dunn procedure were
used in statistical analyses. Twenty-one healthy participants who had refrained from
fluoride-containing products were applied with Duraphat® and ExF2 according to the
protocol of two period cross-over trials. Plaque and saliva samples were collected at 1
and 6 hours, day 1-7 and weekly until one month and were analyzed by the modified
microdiffusion technique. Fluoride level was compared by Wilcoxon match-pair
signed ranks test. Mann-Whitney U test was tested for period and carry-over effects.
All tests were performed at P < 0.05.
The highest fluoride releasing level was at the first day (ExF2 = 1.95±0.95,
Duraphat® = 1.95±0.65, Fluorilaq®
= 3.26±2.65, Fluoridin N5®
=3.45±0.71, Flor-
Opal®
= 43.13±7.73) and then decreased thereafter. In a comparison of mean totals of
fluoride released, ExF2 was not significantly different from some experimental groups
but different from Flor-Opal®. Plaque fluoride levels after application of ExF2 and
Duraphat® significantly elevated from baseline in one (786.48±169.43 and
695.83±97.04 ppm) and six hours after applications(302.09±52.90 and 307.14±54.81).
Salivary fluoride levels were also found significantly elevated in the corresponding
time with those of plaque. The peak levels at one hour of ExF2 and Duraphat® were
17.79±3.99 and 10.13±2.19 ppm, respectively. Fluoride levels of both groups dropped
to 0.66±0.10 and 1.23±0.21 ppm at six hours and decreased over time.
In conclusion, the fluoride releasing pattern of ExF2 was similar to imported
products. The total fluoride content of ExF2 was approaching to Duraphat®, Fluorilaq®
and Fluoridin N5® but less than Flor-Opal®. Plaque and salivary fluoride levels after a
single application of ExF2 were comparable to Duraphat®.