Measuring fluoride in human saliva and water

Background and objective: Fluoride is used to prevent dental caries, and it has been one of the most effective and widespread agents. Fluoride level has been shown in saliva, plaque, and oral soft tissues after use of fluoridated toothpaste that persists at potentially active concentrations for hours. This study aimed to evaluate how fluoride in toothpaste intake can affect the salivary fluoride and test fluoride in tap water in the different places of Erbil city. Methods: Forty five volunteers were examined. In the morning after overnight fasting before brushing teeth, the saliva of the subjects (healthy non-smoker adults) was taken before brushing teeth, which was a baseline. After 10 and 20 minutes of washing mouth with water (after brushing), saliva was taken and then the cotton pad was held under the tongue for 5 min. Saliva samples were frozen at -20 Co for later analysis. Tap water samples in different places in Erbil city were analyzed. Results: Toothpaste significantly (P = 0.002) increased salivary fluoride after brushing teeth. The fluoride concentration of tap water in Erbil city was very low at the places that use groundwater. Conclusion: This research indicates that salivary fluoride significantly increases after brushing teeth. The fluoride concentration naturally occurring levels in the tap water in the places where the source is groundwater are not enough