Fluoride Levels In Saliva Research Articles

Kinetics of fluoride after brushing with the no-rinse method

BackgroundFluoride plays a vital role in preventing dental caries, with its addition to oral care products significantly promoting oral hygiene. A no-rinse brushing method aims to increase fluoride retention in the oral cavity, as rinsing with water decreases fluoride levels in saliva, which could affect remineralization. While the no-rinse brushing method holds promise for improving fluoride retention in the oral cavity, critical inquiries persist regarding its safety. This study investigated the kinetics of oral fluoride and potential risks to fully assess its effectiveness and implications for oral health.MethodsTen healthy adults participated in a crossover study comparing the no-rinse with the rinse method. All subjects followed American Dental Association (ADA) brushing guidelines. Levels of fluoride in saliva (supernatant and sediment) and urine were measured over time, and plasma fluoride was measured one hour after brushing. Pharmacokinetic parameters were also calculated from the data.ResultsParticipants using the no-rinse method had higher fluoride levels in supernatant immediately and up to 30 min post-brushing compared to the rinse method. Fluoride levels in sediment were higher only immediately after brushing. The total fluoride concentration in saliva remained elevated for up to 5 min with the no-rinse method. Systemic fluoride absorption showed no significant difference between the two methods based on blood and urine analysis.ConclusionThis research indicates that the no-rinse method can enhance fluoride retention in the oral cavity for up to 30 min after a single brushing. In addition, our findings suggest that this method does not significantly influence systemic fluoride levels or toxicity.RegistryThai Clinical Trials Registry, TCTR (http://thaiclinicaltrials.org). Clinical trial registration number: TCTR20231104001 (4/11/2023).

COMPARISON FLUORIDE CONCENTRATION IN SALIVA BETWEEN FLUORIDE VARNISH AND GLASS IONOMER CEMENT

Background: Caries is one of the most common dental diseases. Caries prevention by improving dental health has become a major goal in the world of dentistry.Topical application of fluoride is one of the most effective ways to prevent caries.Glass ionomer cement and fluoride varnish has the effect of preventing dental caries because these materials release fluoride. There is no better treatment for demineralization than prevention itself. One of these steps is the combination of dental restorative materials with the application of topical fluoride as an additional source of fluoride.Method: A total of 32 permanent premolar teeth samples, immersed in artificial saliva before and after the application of fluoride varnish and glass ionomer cement. The measurement of fluoride levels in saliva was carried out using a spectrophotometric tool.Result: Independent T-test results obtained sig. below 0.05 indicates that there are differences in the level of fluoride levels between the fluoride varnish group and the glass ionomer cement.Conclusion: Fluoride varnish and glass ionomer cement can increase fluor concentration in salivaÂ

FLUORIDE LEVELS IN SALIVA AFTER CHEWING BLACK TEA CANDY (CAMELLIA SINENSIS) IN CHILDREN

ABSTRACTBackground: Black tea has been shown to affect reducing dental plaque and increasing fluoride levels in saliva. The practice of consuming black tea in the form of candy for dental health purposes is not familiar yet. A study on the effectiveness of chewing black tea candy added with sorbitol sugar for a month on salivary fluoride levels in children aged 7-8 years can be an innovation in the prevention of dental caries. This study aims to investigate the difference in fluoride levels in saliva before and after chewing black tea candy for one month in children aged 7-8 years.Method: This is a field experimental study with double-blind and randomization. Subjects involved in this study were 44 children divided into control and intervention groups using simple random sampling. Measurement of salivary fluorine levels using the TECAN Infinite M200 Pro® UV – VIS Spectrophotometer for 3 times.Result: The results of the independent T-test showed that there were significant differences in the fluorine content in the intervention group using black tea candy on 26 November 2019, 29 November 2019, and 16 December 2019 (p<0.05).Conclusion: Chewing black tea candy is effective in increasing the amount of fluoride in saliva. Thus, it can be an alternative to anti-cariogenic agents.

Fluoride Levels in Unstimulated Whole Saliva following Clinical Application of Different 5% NaF Varnishes

The aim of this study was to evaluate the fluoride release from differently formulated 5% NaF varnishes into unstimulated whole saliva in vivo. The fluoride concentration in unstimulated whole saliva was determined after the application of 3 different 5% NaF varnishes (5% NaF, 5% NaF + tricalcium phosphate [TCP], and 5% NaF + amorphous calcium phosphate [ACP]) or a placebo. Fifteen subjects were recruited and enrolled following Institutional Review Board approval based upon the inclusion/exclusion criteria of this study. A cross-over study design was used for the application of either one of the 5% NaF varnishes or a placebo. Unstimulated whole saliva was collected at baseline and at 1, 4, 6, 26, and 50 h following application and analyzed for supernatant ionic fluoride and whole fluoride by microdiffusion. Linear mixed-effects models (5% significance level) were used to determine the effects of varnish and time on the salivary fluoride concentration. The highest amount of fluoride in saliva was found 1 h after application of the fluoride varnishes, with no significant differences among the treatment varnishes with respect to whole fluoride but with lower levels for 5% NaF + ACP in the saliva supernatant. Salivary fluoride levels at 4, 6, and 26 h decreased at each time point and were generally significantly higher for 5% NaF and 5% NaF + TCP. After 50 h, fluoride levels in saliva for all groups were at or below baseline levels. In conclusion, the formulation of other ingredients in fluoride varnishes can affect the fluoride concentration in saliva. The reasons for this phenomenon warrant further investigation since it might affect efficacy of the treatment. This trial is registered at ClinicalTrials.gov (NCT01629290).

Effects of pH and fluoride concentration of dentifrices on fluoride levels in saliva, biofilm, and biofilm fluid in vivo.

Acidic dentifrices have been shown to be more effective than neutral ones against dental caries using in vitro, in situ, and clinical protocols. Given the scarcity of studies assessing intraoral fluoride (F) retention after using such formulations, the present study evaluated the influence of pH and F concentration of dentifrices on F uptake by saliva, biofilm, and biofilm fluid. Volunteers (n = 22) were randomly assigned to dentifrices containing 0 (placebo), 550 (LFD, low-fluoride dentifrice), and 1100ppmF (CD, conventional dentifrice) at pH4.5 and 7.0 and brushed their teeth 3 times/day following a double-blind, crossover protocol. Saliva and biofilm samples were collected after 7days of using the dentifrices, 1 and approximately 12h after last brushing. F and calcium (Ca) analyses were performed with the inverted electrode after buffering with TISAB III and the Arsenazo III method, respectively. Data were analyzed by 3-way ANOVA, Tukey's HSD test, and Pearson's correlation coefficient (p < 0.05). F concentrations in biofilm fluid and whole biofilm 1h after brushing with acidic F-toothpastes were higher than those related to neutral counterparts, although the differences were small and not significant; no increases were observed in salivary F concentrations influenced by dentifrice pH. Moreover, no definite trend was observed for Ca concentrations in these compartments. Dentifrice pH had some influence on F uptake by the biofilm fluid, having lesser or no impact on F uptake by the biofilm and saliva, respectively. Toothbrushing with acidic toothpastes leads to slight increases in F concentrations in the biofilm fluid when compared to neutral formulations, which may contribute to the higher anticaries effect of acidic formulations.

Evaluation of the influence of serum and salivary fluoride levels on periodontal disease status in endemic fluorosis patients

Background: The major determinant of the prevalence and severity of dental fluorosis has been shown to be the concentration fluoride in the water consumed, but limited studies are available evaluating the effects of fluoride concentration on periodontal disease status. Aims: The aim of this study is to estimate the levels of fluoride in saliva, serum and in ground water of the villages where the subjects hail from and to correlate the levels of fluoride in serum and saliva to the periodontal disease severity. Materials and Methods: A total number of 120 subjects selected for the study are divided into two groups. Group A (test group) consisted of dental subjects diagnosed with dental fluorosis and periodontitis. Group B (control group) consisted of 20 non-fluorosed subjects. Assesment of fluoride in saliva and serum has been done by ion selective electrode method. The periodontal status was measured using the community periodontal index and clinical attachment level? Scores and were compared between the groups. Statistical Analysis Used: Correlation of altered fluoride levels in serum and saliva to the periodontal disease severity was done using the Pearson correlation coefficient and one-way analysis of variance was used for inter group comparison. Results and Conclusions: No correlation was found between salivary and fluoride levels and the periodontal disease severity. However, mean salivary fluoride levels were found to significantly influence the dental fluorosis severity.

Saliva fluoride before and during 3 years of supervised use of fluoride toothpaste

The purpose of the study was to examine pre-brushing saliva fluoride concentrations before and during a large, 3-year, prospective toothpaste study on the effect of post-brushing rinsing on dental caries. The aims were to study saliva fluoride over time and the effect of rinsing on saliva fluoride and to relate saliva fluoride to caries increments and accumulation of plaque. Saliva samples (baseline and 1, 2, and 3 years) were collected from 11-year-old children attending two schools (A and B) in Kaunas, Lithuania, who refrained from brushing the evening and morning before saliva collection. Numbers of saliva samples collected varied from 264 at baseline to 188 at the 3-year follow-up. Children in school A rinsed with water after daily brushing, while children in school B did not rinse. Total caries and visible plaque were registered at baseline and after 3 years. Mean saliva fluoride concentrations at baseline and after 1, 2, and 3 years from school A (rinsing) were 0.014, 0.026, 0.029, and 0.034 ppm and from school B (no rinsing) were 0.013, 0.028, 0.031, and 0.031 ppm, respectively. Increases in saliva fluoride from baseline were significant (Wilcoxon's test, p < 0.001), but the increase from baseline to year 1 was not statistically significantly different between schools. Saliva fluoride did not increase beyond year 1 and did at no time point differ between schools. Reductions in numbers of tooth surfaces with dental plaque were significantly positively related to the number of caries reversals over the 3 years. Background saliva fluoride concentration is increased by brushing at least once daily on schooldays, does not increase further over 3 years, and is not affected by rinsing after brushing. Continuous use of fluoride toothpaste produces ambient saliva fluoride levels similar to saliva fluoride in areas with fluoridated water.

Caries and fluoride processes

The purpose of the work was to establish the level and source of salivary fluoride, whether it could interact with tooth mineral and whether it was able to effect calcium re-acquisition and remineralisation. Fluoride in saliva and in solution was measured by electrode, calcium by complexometric titration and phosphate colourimetrically-to measure salivary fluoride, its uptake by mineral and the effects of such low levels on calcium and phosphate levels in solution in contact with suspensions of mineral hydroxyapatite. Fluoride levels in saliva were low but could interact with hydroxyapatite. Such levels caused apatite crystallite growth and preferential acquisition of calcium by calcium-deficient apatite. Salivary fluoride contents rose with increasing water fluoride levels. It was acquired by hydroxyapatite mineral. Topical fluoride was stored on oral tissues. Even these low fluoride contents could cause mineral crystallite growth with preferential calcium uptake. On a mineral area basis these effects were caused by quite low fluoride uptakes. These findings do not support reliance upon large fluoride uptakes by tooth enamel as evidence for commensurate caries reductions.

Fluoride Concentrations of Unstimulated Whole and Labial Gland Saliva in Young Adults after Fluoride Intake with Milk

Following a fluoride depletion period 6 subjects repeatedly rinsed with 30–ml volumes of milk with or without added fluoride (5 ppm). Rinsing time was timed according to the measurements on how long it took to drink 200 or 500 ml milk. Rinsing with fluoridated milk for a total interval of 20 and 60 s, respectively, did not influence significantly the fluoride concentration of unstimulated centrifuged whole saliva 45 min later. Neither the urinary fluoride concentration nor the fluoride excretion were significantly affected by rinsing with fluoridated milk during the first hour. However, intake of 1 or 2.5 mg of fluoride with 200 and 500 ml milk, respectively, resulted in significant elevations in whole saliva fluoride levels 45 min later. In addition, the fluoride excretions into urine produced during 60 min after the fluoride intakes were significantly elevated and those reflected the ingested dose of fluoride. The intake of either 1 or 2.5mg fluoride with milk did not significantly influence the fluoride level of unstimulated labial gland saliva collected simultaneously with whole saliva.

Prevention and reversal of dental caries: role of low level fluoride.

Dental caries is a bacterially based disease that progresses when acid produced by bacterial action on dietary fermentable carbohydrates diffuses into the tooth and dissolves the mineral, that is, demineralization. Pathological factors including acidogenic bacteria (mutans streptococci and lactobacilli), salivary dysfunction, and dietary carbohydrates are related to caries progression. Protective factors which include salivary calcium, phosphate and proteins, salivary flow, and fluoride in saliva can balance, prevent or reverse dental caries. Fluoride works primarily via topical mechanisms which include (1) inhibition of demineralization at the crystal surfaces inside the tooth, (2) enhancement of remineralization at the crystal surfaces (the resulting remineralized layer is very resistant to acid attack), and (3) inhibition of bacterial enzymes. Fluoride in drinking water and in fluoride-containing products reduces tooth decay via these mechanisms. Low but slightly elevated levels of fluoride in saliva and plaque provided from these sources help prevent and reverse caries by inhibiting demineralization and enhancing remineralization. The level of fluoride incorporated into dental mineral by systemic ingestion is insufficient to play a significant role in caries prevention. The effect of systemically ingested fluoride on caries is minimal. Fluoride "supplements" can be best used as a topical delivery system by sucking or chewing tablets or lozenges prior to ingestion.

Current concepts on the theories of the mechanism of action of fluoride

The caries-preventive effect of fluoride is mainly attributed to the effects on demineralization/remineralization at the tooth-oral fluids interface. Sub ppm levels of fluoride in saliva are effective in shifting the balance from demineralization, leading to caries, to remineralization. This is attributed to the fluoride-enhanced precipitation of calcium phosphates, and the formation of fluorhydroxyapatite in the dental tissues. Low fluoride levels are found in saliva after toothbrushing with fluoride containing dentifrices. Similar concentrations are ineffective in interfering with processes of growth and metabolism of bacteria, and also do not result in a significantly reduced dissolution of tooth mineral as a result of (firmly bound) fluoride incorporation. Comparative studies of fluoride efficacy have shown that higher concentrations in solution are needed in pH-cycling studies of dentine than in enamel to maintain the mineral balance or to induce remineralization. This is attributed to the greater solubility of the dentine and the smaller size of the dentine crystallites compared to enamel. Fluoride slow-release devices, in the form of fluoride-releasing restorative materials, may serve to increase the fluoride levels in saliva and plaque to levels at which caries can be prevented, also in high-risk patients. Research questions for the next millennium and future perspectives for fluoride applications should be found in the retention and slow release of fluoride after various combinations of fluoride treatment, the combination of fluoride and anti-microbial treatment, the individualization of caries prevention, and the combination of preventive schemes with new developments in caries diagnosis.

PH-cycling of enamel and dentin lesions in the presence of low concentrations of fluoride.

F-dentifrice usage causes slightly elevated fluoride levels in saliva. Therefore, the effects of permanent low fluoride concentrations versus daily dentifrice treatments were studied on enamel and dentin lesions in a pH-cycling model of alternating demineralization and remineralization. Groups received 1) no fluoride treatment, 2) 3 mu M (0.06 ppm) F continuously present during re- and demineralization or 3) daily 5-min F-dentifrice treatments. Solutions were analyzed for changes in calcium and fluoride. Cumulative results (10 d) showed that for the non-fluoride group the dentin lesions increased, while for enamel lesions mineral uptake and loss were balanced. Addition of 3 mu M F caused small, non-significant, enhancement of remineralization (1-7%), while demineralization was significantly inhibited for both tissues (9-23%). The daily dentifrice treatments resulted in a balance between mineral uptake and loss of dentin, due to inhibited demineralization (-33%) and enhanced remineralization (+79%). For enamel, the F-dentifrice treatments resulted in 43% reduction of demineralization, with no significant effect on remineralization. Fluoride loss from the 3 mu M F cycling solutions was significant (up to 50%) and constant during the experimental period. Microradiographic analysis showed remineralization at the lesion front in enamel. In dentin, the lesion depth was increased in all groups, with concomitant mineral deposition in the surface region of the dentifrice group. Results indicate that slightly elevated fluoride levels may be considerably less effective in inhibiting lesion progression in dentin than in enamel, and suggest mineral uptake and loss to occur at similar depths for enamel lesions, while demineralization and remineralization occur at different depths in dentin.

Estimation of Fluoride Absorption from Swallowed Fluoride Toothpastes

Eight adults ingested five different toothpastes with and without 1,000 ppm (1 microgram/g) fluoride added as NaF or Na2PO3F. The systemic fluoride absorption was estimated by by comparing the areas under salivary fluoride concentration curves produced after the toothpaste ingestion. Of the toothpastes investigated--chalk, dicalcium phosphate dihydrate, silica or alumina with sodium monofluorophosphate, and silica with sodium fluoride--the fluoride absorption was found to be statistically significantly lower only from the dicalcium phosphate dihydrate toothpaste. Measuring changing fluoride levels in saliva appears to be an acceptable non-invasive technique for following systemic fluoride absorption.

Retention of topical fluoride in the mouths of xerostomic subjects.

The total fluoride concentration in unstimulated whole saliva was measured before and at selected intervals after a self-applied 1.1% neutral NaF topical fluoride gel or use of a 0.05% neutral NaF fluoride mouthrinse in both normal individuals and patients with radiation-induced xerostomia. As expected, the gel resulted in higher peak fluoride values than the rinse and was retained in the mouth for longer periods of time in both groups. The xerostomic group expressed a mean oral fluoride concentration of 575 micrograms fluoride per gram of saliva within 1 min after the gel application and 150 micrograms/g following use of the mouthrinse, whereas the normal group exhibited peak concentrations of 112 and 71 micrograms/g, respectively, within 1 min after the same two treatments. The initial high levels of fluoride observed in normal subjects following the gel application decreased rapidly to less than 1 microgram/g within 2 h, whereas fluoride levels in the xerostomic subjects remained elevated above 12 micrograms/g for longer than 2 h. Similarly, following use of the mouthrinse, normal subjects' saliva fluoride levels decreased to less than 1 microgram/g within 1 h, whereas xerostomic subjects' saliva fluoride levels remained above 4 micrograms/g for longer than 2 h.

Effective delivery systems for prolonged fluoride release: review of literature

Controlled-release delivery systems have been investigated for use in fluoride therapy as a result of their ability to control the rate and site of fluoride release. Both sustained-release fluoride delivery systems and controlled-release fluoride preparations have been developed, including sustained-release fluoride tablets, fluoride-releasing polymers, microencapsulated fluoride in aerosols, and membrane-controlled fluoride reservoirs. Laboratory and clinical studies have confirmed the ability of these preparations to produce high levels of fluoride in saliva and plaque without toxic or adverse side effects. From these studies, it appears that controlled-release fluoride delivery systems have great potential as effective anticaries agents in cariesprone populations.

Clinical Evaluation of an Intraoral Device for the Controlled Release of Fluoride

An intraoral-releasing device designed to release 0.5 mg of fluoride per day was evaluated in a one-month trial. The results showed that the 11 men who wore the fluoride-releasing device on their maxillary first molars had significantly elevated levels of fluoride in their saliva and plaque compared with baseline levels. No significant changes were observed in mean serum or urine fluoride levels or in the gingival or plaque indexes during the study. The prevalence of S mutans in whole saliva did not change during the study and the relative proportion of S. mutans, S. sanguis, and A viscosus and A naeslundii in plaque also remained relatively stable. The elevated fluoride levels in saliva and plaque are presumptive evidence that the intraoral fluoride-releasing device could exert a cariostatic effect in humans. However, long-term clinical trials are needed to determine the cariostatic potential of this fluoride releasing system.

Systemic absorption of fluoride from alginate impression material in humans.

Thirty minutes after routine alginate impressions in five adult subjects, plasma fluoride levels increased by an average of 2.6 times over control values. Urinary fluoride excretion rates increased approximately 2.9 times during the first two hours after the impressions. Average whole saliva fluoride levels at 15 minutes were over 100 times the average control concentration. When small amounts of alginate were deliberately ingested, plasma fluoride levels and urinary excretion rates increased sharply.

Fluoride concentrations in saliva in relation to chewing of various supplementary fluoride preparations

Fluoride concentrations were measured in whole saliva samples collected from 16 subjects at different intervals up to 60 min after chewing of various supplementary F preparations: chewable F tablets (0.21 mg F), plain F tablets (0.25 mg F) or F-containing chewing gum (0.25 mg F). Each of the F preparations was administered in a low dose (0.21--0.25 mg F) or in a high dose (0.42--0.50 mg F). Mean resting levels of fluoride in saliva ranged from 0.03 to 0.05 parts/10(6). Peak values averaging 15--25 parts F/10(6) in the low-dose group and 25--40 parts F/10(6) in the high-dose group were recorded within 5 min after intake. After 30 min, the salivary fluoride concentrations in both groups had decreased to levels below 1 part/10(6) and approached resting levels 60 min after intake. The availability of fluoride in saliva, as estimated from AUC values (areas under curves, relating fluoride concentrations to the time from 0 to 60 min), was similar with each of the preparations applied in the low dose. When used in the high dose, the chewing gum and also the plain tablets provided significantly more fluoride in saliva than the chewable tablets. The data may suggest that unflavored plain F tablets are equally suitable as a vehicle for fluoride aiming at a topical cariostatic effect as specially designed chewable tablets or chewing gum.

Effect of rate of gland function on parotid saliva fluoride concentration in the human.

A series of experiments were carried out to determine the effect of the rate of gland function on parotid saliva fluoride levels in the human. Means for fluoride for stimulated parotid saliva ranged from 0.012 to 0.02 ppm. These are much lower levels than those previously reported for whole saliva and support other electrode analyses recently reported. In a 3-hour experiment involving continuous exogenous stimulation, salivary fluoride levels showed no alterations suggestive of depletion. Significantly higher levels of fluoride were found in parotid saliva collected without exogenous stimulation. It is suggested that the glandular mechanisms responsible for these observations are purely passive in nature with the fluoride ion probably moving in bulk flow with the fluid of secretion as it is generated by the secretory cells. However, the exact mechanisms which govern absolute saliva fluoride levels remain obscure.