Fluoride Kinetics Research Articles

Release of Fluoride in Saliva the Use Chewing Gums with Different Fluoride Compounds NaMFP, SnF2 and Naf

The goal of search determine the effect of use commercially chewing gums on fluoride kinetics in saliva. Using of three commercially chewing gums with fluoride from local markets, contains 3.38 mg of fluoride as marketed sodium mono fluorophosphates (NaMFP), Stannous fluoride (SnF2) and sodium fluoride (NaF) which are the three most common sources of fluoride used in currently fluoride dentifrices. Fifteen 7–9 year-old volunteers were instructed to chew the fluoridated gums. After starting chewing saliva collected at 0, 3, 6, 9 and 15 minutes. The Salivary fluoride analyzed by using of fluoride-specific electrode (201Fluoride E. Hanna instruments) after acid hydrolysis. The fluoride amount in the saliva samples after the use of chewing gum which contains Sodium mono-fluorophosphates (NaMFP) and Stanous fluoride (SnF2), were 0.328 mg and 0.258 mg respectively which higher than after the use of chewing gum contains sodium fluoride (NaF) which was 0.041mg in all experimental periods. The high fluoride presence in saliva after the use of chewing gum of (NaMFP) and (SnF2), are significant to prevent dental caries and this should be evaluated in clinical researches.

Nitric oxide-mediated vasodilation increases blood flow during the early stages of stress fracture healing

Despite the strong connection between angiogenesis and osteogenesis in skeletal repair conditions such as fracture and distraction osteogenesis, little is known about the vascular requirements for bone formation after repetitive mechanical loading. Here, established protocols of damaging (stress fracture) and nondamaging (physiological) forelimb loading in the adult rat were used to stimulate either woven or lamellar bone formation, respectively. Positron emission tomography was used to evaluate blood flow and fluoride kinetics at the site of bone formation. In the group that received damaging mechanical loading leading to woven bone formation (WBF), (15)O water (blood) flow rate was significantly increased on day 0 and remained elevated 14 days after loading, whereas (18)F fluoride uptake peaked 7 days after loading. In the group that received nondamaging mechanical loading leading to lamellar bone formation (LBF), (15)O water and (18)F fluoride flow rates in loaded limbs were not significantly different from nonloaded limbs at any time point. The early increase in blood flow rate after WBF loading was associated with local vasodilation. In addition, Nos2 expression in mast cells was increased in WBF-, but not LBF-, loaded limbs. The nitric oxide (NO) synthase inhibitor N(ω)-nitro-l-arginine methyl ester was used to suppress NO generation, resulting in significant decreases in early blood flow rate and bone formation after WBF loading. These results demonstrate that NO-mediated vasodilation is a key feature of the normal response to stress fracture and precedes woven bone formation. Therefore, patients with impaired vascular function may heal stress fractures more slowly than expected.

KrF Laser Development for Fusion Energy

The United States Naval Research Laboratory is developing an electron beam pumped krypton fluoride laser technology for a direct drive inertial fusion energy power plant. The repetitively pulsed krypton fluoride laser technology being developed meets the fusion energy requirements for laser beam quality, wavelength, and repetition rate. The kryptonfluoride laser technology is projected, based on experiments, to meet the requirements for wall plug efficiency and durability. The projected wall plug efficiency based on experiments is greater than 7 percent. The Electra laser using laser triggered gas switches has conducted continuous operation for 90,000 shots at 2.5 Hertz operation (ten hours). The Electra laser has achieved greater than 700 Joules per pulse at 1 and 2.5 Hertz repetition rate. The comparison of krypton fluoride laser performance with krypton fluoride kinetics code shows good agreement for pulse shape and laser yield. Development and operation of a durable pulse power system with solid state switches has achieved a continuous run of 11 million pulses into a resistive load at 10Hz.

Differences in regional bone metabolism at the spine and hip: a quantitative study using 18F-fluoride positron emission tomography

This study showed that regional bone blood flow and (18)F-fluoride bone plasma clearance measured by positron emission tomography are three times lower at the hip than the lumbar spine. Measurements of effective bone plasma flow (K (1)), bone plasma clearance (K ( i )) and standardised uptake values (SUV) using (18)F-fluoride positron emission tomography ((18)F-PET) provide a useful means of studying regional bone metabolism at different sites in the skeleton. This study compares the regional (18)F-fluoride kinetics and SUV at the hip and lumbar spine (LS). Twelve healthy postmenopausal women with no history of metabolic bone disease apart from two with untreated osteoporosis were recruited. Each subject underwent 60-min dynamic (18)F-PET scans at the LS and proximal femur two weeks apart. K (1), K ( i ) and SUV were measured at the LS (mean of L(1)-L(4)), femoral neck (FN), total hip (TH) and femoral shaft (FS). Differences between sites were assessed using the nonparametric Kruskal-Wallis test with a Bonferroni correction for multiple comparisons. Values of K (1), K ( i ) and SUV at the FN, TH and FS were three times lower than at the LS (p = 0.003). Amongst the proximal femur sites, K ( i ) and SUV were lower at the FS compared with the FN and TH, and SUV was lower at the TH compared with the FN (all p < 0.05). The volume of distribution was lower at the TH and FS compared with the LS (p < 0.05). The lower values of K (1), K ( i ) and SUV at the hip suggest that lower bone blood flow in the proximal femur is an important factor explaining the principal reason for the differences in bone fluoride kinetics between the LS and hip sites.

Kinetics of fluoride bioavailability in supernatant saliva and salivary sediment

The assessment of the fluoride kinetics in whole saliva as well as in the different salivary phases (supernatant saliva and sediment) is essential for the understanding of fluoride bioavailability. ObjectivesTo assess the fluoride content, provided by sodium fluoride and amine fluoride, in the supernatant saliva and in salivary sediment. MethodsSeven trained volunteers were randomly attributed to 2 groups in a cross-over design and brushed their teeth in the morning for 3min with a product containing either sodium fluoride or amine fluoride. Saliva was collected before, immediately after tooth brushing and 30, 120, and 360min later and measured. The samples were centrifuged 10min at 3024×g. Fluoride content of the supernatant saliva and of the sediment was analysed using a fluoride sensitive electrode. All subjects repeated the study cycles 2 times, and statistical analyses were made using the nonparametric sign test for related samples, the Wilcoxon–Mann–Whitney-test for independent samples. ResultsThere was a significant increase in fluoride immediately after tooth brushing in both groups in saliva and sediment. The distribution of fluoride between salivary sediment and supernatant saliva (ratio) varied considerably at the different collection times: decreased from 17.87 in baseline samples of saliva to 0.07 immediately and to 0.86 half an hour after tooth brushing in the sodium fluoride group and from 14.33 to 2.85 and to 3.09 in the amine fluoride group. Furthermore after 120min and after 360min after tooth brushing the ratio increased from 17.6 to 31.6 in the sodium fluoride group and from 20.5 to 25.76 in the amine fluoride group. No difference was found in the sediment–supernatant saliva ratio between the sodium fluoride and the amine fluoride groups 360min after tooth brushing. ConclusionFor the assessment of fluoride kinetics in whole saliva it is necessary to pay attention to at least four factors: fluoride formulation, time after fluoride application, fluoride concentration in supernatant saliva and fluoride concentration in salivary sediment. This study was approved by the Ethical Committee of the University of Witten/Herdecke permission 21/2008.

The comparison study of Fluoride kinetics in saliva after the use of chewing gums containing different fluoride compounds In Iraqi subjects

There is a relationship between the use of fluoride, the reduction of dental caries and the increase of dental fluorosis. The purpose of this study was to analyze the fluoride kinetics in saliva after using two commercially available chewing gums with fluoride, which contains (3.38) mg of fluoride as marketed Sodium monofluorophosphate (NaMFP) and sodium fluoride (NaF) which are the two most common sources of fluoride used in currently fluoride dentifrices.Fifteen 7-9 year-old volunteers were instructed to chew the fluoridated gums. Total saliva was collected, at 0, 3, 6, 9 and 15 minutes after 3 minutes starting chewing. Salivary fluoride was analyzed with a fluoride-specific electrode (201 Fluoride E. HANNA instruments) after acid hydrolysis.The fluoride amount in the saliva samples after the use of chewing gum which contains Sodium monofluorophosphate (NaMFP) was 0.4 mg which higher than after the use of chewing gum contains sodium fluoride (NaF) which was 0.041mg in all experimental periods, The high fluoride presence in saliva after the use of chewing gum of (NaMFP) is significant to prevent dental caries and this should be evaluated in clinical researches. On the other hand, children at an age of risk for dental fluorosis should avoid the use of this kind of chewing gums.

Quantification of Skeletal Blood Flow and Fluoride Metabolism in Rats using PET in a Pre-Clinical Stress Fracture Model

Blood flow is an important factor in bone production and repair, but its role in osteogenesis induced by mechanical loading is unknown. Here, we present techniques for evaluating blood flow and fluoride metabolism in a pre-clinical stress fracture model of osteogenesis in rats. Bone formation was induced by forelimb compression in adult rats. (15)O water and (18)F fluoride PET imaging were used to evaluate blood flow and fluoride kinetics 7 days after loading. (15)O water was modeled using a one-compartment, two-parameter model, while a two-compartment, three-parameter model was used to model (18)F fluoride. Input functions were created from the heart, and a stochastic search algorithm was implemented to provide initial parameter values in conjunction with a Levenberg-Marquardt optimization algorithm. Loaded limbs are shown to have a 26% increase in blood flow rate, 113% increase in fluoride flow rate, 133% increase in fluoride flux, and 13% increase in fluoride incorporation into bone as compared to non-loaded limbs (p < 0.05 for all results). The results shown here are consistent with previous studies, confirming this technique is suitable for evaluating the vascular response and mineral kinetics of osteogenic mechanical loading.

Influence of Individual Saliva Secretion on Fluoride Bioavailability

The aim of this preliminary investigation was to compare the individual saliva secretion rate with the fluoride bioavailability in saliva after using sodium fluoride and amine fluoride.Methods:To assess oral fluoride kinetics 10 highly trained volunteers brushed their teeth with one of the formulations and saliva was collected. The amount of saliva was measured, and the fluoride content was determined. Data underwent statistical analysis using the Mann-Whitney-U test and Pearson correlation. The ex vivo experiment I included individual saliva collection of the same volunteers. Then the oral hygiene products were solved in equal amounts of whole saliva (ex-vivo experiment II), and the fluoride content was measured. Finally, both products were dispersed in distilled water (ex-vivo experiment III) to calculate the dissociation of both products in water.Results:In vivo results of fluoride content after 3 min. tooth brushing demonstrated a negative correlation with saliva secretion: for NaF r = -0.695 (p<0.01) and for amine fluoride r = -0.446 (p<0.01). The in-vitro experiment I resulted for NaF in 251.7±22.4 µg/g fluoride and for amine fluoride in 171.7±14.4 µg/g.Conclusions:Fluoride bioavailability of saliva after exposure to NaF was higher compared to amine fluoride. The individual secretion rate changes the fluoride content and normal secretors keep the fluoride availability longer.

Theoretical context-sensitive elimination times for inhalation anaesthetics

Context-sensitive times to 50%, 80%, and 90% elimination from the brain have been calculated for volatile anaesthetics. This does not represent complete recovery because there are important residual effects even at 90% elimination, and the effect of anaesthetic metabolism on the rate of elimination has not been considered. A physiologically based model of anaesthetic uptake and distribution was elaborated to include anaesthetic metabolism and fluoride kinetics. It was validated by comparing its predictions with real data, then experiments were undertaken to calculate the partial pressure of anaesthetic in the brain after the administration of 1 MAC of halothane, enflurane, isoflurane, sevoflurane or desflurane, or 50% of inspired nitrous oxide or xenon, for up to 6 h. The model generated data that were compatible with many published measurements of anaesthetic kinetics and fluoride production. Metabolism had a negligible effect on kinetics. After 4 h of anaesthesia, the model predicted body content to be 28 g nitrous oxide, 26 g desflurane, 14 g sevoflurane, or 15 g isoflurane, and 99.9% brain elimination times were then 9 h for nitrous oxide, 33 h for desflurane, 52 h for sevoflurane, and 71 h for isoflurane. At this stage of elimination, the whole body still retained between 4% and 13% of the absorbed dose. Differences between sevoflurane and desflurane were obvious only during the final stages of elimination (>99% from the vessel-rich group). Large amounts of anaesthetics are absorbed during anaesthesia and significant amounts remain in the body for days after apparent recovery.

Effect of Long-term Fluoride Exposure on Growth, Nutrient Utilization and Fluoride Kinetics of Calves Fed Graded Levels of Dietary Protein

In order to assess the influence of dietary protein levels on the fluoride (F) bioavailability, 30 crossbred calves (6-8 months; approximately 104 kg BW) initially exposed to different dietary protein levels were allotted into six groups in a 3 × 2 factorial design. The factors included three different levels of protein viz. normal (100%; NP), low (75%; LP), and high (125%; HP) as per Kearl recommendations besides two levels of supplemental fluorine (as sodium fluoride) at 0 or 200 mg/kg diet. The animals were fed on the respective concentrate mixture and wheat straw for 210 days. A metabolism trial was conducted at 200 days post-feeding to study digestibility, plane of nutrition, and nutrient balances. The final body weight at the end of 210 days was lower (p < 0.01) in animals fed 200 mg/kg F (164.2 ± 8.92 kg) compared to those fed no F (200.7 ± 8.05 kg). Calves on LP diets attained lower (p < 0.05) average daily gain in comparison to NP or HP fed calves. The F-supplemented calves exhibited lower (p < 0.01) voluntary feed intake than their non-supplemented control. The digestibility of proximate nutrients other than ether extract exhibited higher (p < 0.01) values in F-fed calves attributable chiefly to reduced consumption of dry matter. The calves fed extra F retained lower mean daily nitrogen; calcium, and phosphorus compared to the calves fed no F. The mean daily intake, excretion, and retention of F were higher (p < 0.01) in the F-supplemented calves. A significant (p < 0.01) interaction between protein levels and F was evident in the urinary excretion of F; calves on LP diet exhibiting lower urinary excretion. Consequently, the bioavailability of F tended to be higher on LP than NP or HP diets. From the results, it is concluded that protein levels in the diet do not impart significant influence on susceptibility to fluorosis in crossbred calves. However, the bioavailability of F tended to increase on diets low in protein.

Time‐dependent Changes of Blood Parameters and Fluoride Kinetics in Rats after Acute Exposure to Subtoxic Hydrofluoric Acid

In our previous study, we reported that even a sublethal dose of hydrofluoric acid (HFA) could cause acute toxic effects 60 min after intravenous injection. This study was designed to investigate the time- and dose-dependent changes associated with these disorders. The serum fluoride (F) kinetics are also considered in the discussion of the relationship between the concentrations of serum F and the disorders. Rats were injected with HFA (1.6 or 9.6 mg/kg body weight) for the dose-response relationship study. For each dose, the rats were assigned to one of seven groups. Blood samples of the 0-min group were obtained from the carotid artery prior to injection as a control. The other six groups were labeled according to sampling times (5, 10, 30, 60, 120 and 300-min) in the time-dependent study. The 1.6 mg/kg dose decreased the ionized calcium (Ca2+) level significantly after 30 min, and it also decreased the total calcium (Ca) level after 300 min. The 9.6 mg/kg dose rapidly worsened renal dysfunction after 60 min. It increased the serum potassium level after 60 and 120 min and it decreased Ca and Ca2+ levels until 300 min. Although there was respiratory compensation, the base excess and HCO3(-) level and had not completely recovered by 300 min. Even low exposure to HFA caused renal dysfunction, and electrolyte abnormalities and metabolic acidosis lasted for several hours in rats. Therefore, persons involved in HFA accidental exposure should be closely monitored over time, even if the exposure is less than the sublethal dose.

Changes of acute harmful effects and fluoride kinetics after single intravenous injection of sub-toxic hydrofluoric acid in rats

Changes of acute harmful effects and fluoride kinetics after single intravenous injection of sub-toxic hydrofluoric acid in rats

Abnormalities in Cadmium Fluoride Kinetics in Serum, Bile, and Urine after Single Intravenous Administration of Toxic Doses to Rats

Cadmium fluoride (CdF2, CdF for short) is the most lethal and hepatotoxic of all Cd-containing compounds. The toxic effects of CdF appear to depend on its detoxification and elimination. This study was designed to determine the early dynamics of the absorption, systemic distribution, and metabolism of CdF. The kinetics of cadmium and fluoride were investigated in the blood, bile, and urine of rats as a model of accidental occupational exposure to CdF. The serum concentration-time profiles measured after intravenous CdF (1.34, 2.67 or 4.01 mg/ per kg body weight) administration were analyzed by compartmental modeling using the WinNonlin program. Bile and urine were collected for 300 min after the administration. The kinetic profiles indicate that the clearance of Cd was diminished in the 2.67 and 4.01 mg/kg groups, leading to a persistently high serum Cd level. The mean total biliary excretions of Cd in the 2.67 and 4.01 mg/kg groups were significantly higher than that in the 1.34 mg/kg group. The abnormal kinetics of Cd was attributable to severe hepatic injury that diminished the capacity for Cd accumulation. The elimination of serum F was delayed in the 4.01 mg/kg group. The mean urinary F excretion amount was not significantly higher in the 4.01 mg/kg group than in the 2.67 mg/kg group. The abnormal kinetics of F was attributable to nephrotoxicity that diminished its elimination from the kidney.

Fluoride kinetics in saliva after the use of a fluoride-containing chewing gum

There is a relationship between the use of fluoride, the reduction of dental caries and the increase of dental fluorosis. The purpose of this study was to analyze the fluoride kinetics in saliva after using the Happydent chewing gum, which contains 3.38 mg of fluoride as monofluorophosphate. Fifteen 7-9-year-old volunteers were instructed to chew the gum Trident (control) and Happydent on different days. Total saliva was collected for 3 minutes, at 0, 3, 6, 9, 15, 30 and 45 minutes after starting chewing. Salivary fluoride was analyzed with a fluoride-specific electrode (Orion 96-09) after acid hydrolysis. The data were analyzed by two-way analysis of variance and by Tukeys post hoc test (p < 0.05). The mean amounts +/- sd (mg) of fluoride released in saliva were 0.276 +/- 0.126 and 0.024 +/- 0.014 for Happydent and Trident respectively. The fluoride amount in the saliva samples after the use of Happydent was significantly higher than after the use of Trident in all experimental periods, except after 30 and 45 minutes. The high fluoride presence in saliva after the use of Happydent may be significant to prevent dental caries and this should be evaluated in clinical researches. On the other hand, children at an age of risk for dental fluorosis should avoid the use of Happydent.

Inorganic Fluoride Kinetics and Renal and Hepatic Function After Repeated Sevoflurane Anesthesia

Inorganic Fluoride Kinetics and Renal and Hepatic Function After Repeated Sevoflurane Anesthesia

Inorganic Fluoride Kinetics and Renal and Hepatic Function After Repeated Sevoflurane Anesthesia

After repeated exposure to inhaled anesthetics, the hepatic function and metabolism of anesthetics may change. The purpose of this study was to investigate inorganic fluoride (F-) kinetics and renal and hepatic function after repeated exposure to sevoflurane. Ten patients (aged 40-70 yr) who had received sevoflurane anesthesia with a gas flow of 6 L/min for neurosurgery twice in 30-90 days were studied. Serum and urine F- concentrations were measured up to 24 h after anesthesia. Blood urea nitrogen, serum creatinine, serum and urine beta2-microglobulin, urine N-acetyl-beta-D-glucosaminidase, serum aspartate aminotransferase (AST), alanine aminotransferase (ALT), and total bilirubin concentrations were measured up to 7 days after anesthesia. The area under the curve (AUC) of serum and urine F- concentration and half-life of serum F concentration were calculated. Urine beta2-microglobulin, AST, and ALT increased to abnormal levels after both anesthesias, with no difference between anesthesias. No measured variables, AUC of serum and urine F- concentration, or half-life of serum F- concentration showed any differences between the first and second anesthesias. In conclusion, the second exposure to sevoflurane with a high gas flow of 6 L/min in 30-90 days did not change the hepatic and renal function or affect the metabolism of sevoflurane. We studied the changes of metabolism of sevoflurane and hepatic and renal function after repeated sevoflurane anesthesia in 30-90 days. There were changes indicative of mild liver and kidney injury after sevoflurane anesthesia, but repeated exposure to sevoflurane did not enhance these changes.

Inorganic Fluoride Kinetics and Renal and Hepatic Function After Repeated Sevoflurane Anesthesia

Inorganic Fluoride Kinetics and Renal and Hepatic Function After Repeated Sevoflurane Anesthesia

Inorganic Fluoride Kinetics and Renal Tubular Function After Sevoflurane Anesthesia in Chronic Renal Failure Patients Receiving Hemodialysis

Inorganic Fluoride Kinetics and Renal Tubular Function After Sevoflurane Anesthesia in Chronic Renal Failure Patients Receiving Hemodialysis

Inorganic fluoride kinetics and renal tubular function after sevoflurane anesthesia in chronic renal failure patients receiving hemodialysis.

Although sevoflurane is used in clinical anesthesia, its effects on renal function and inorganic fluoride (F-) kinetics in patients with chronic renal failure (CRF) have not been determined. We investigated F- kinetics and renal tubular function in sevoflurane anesthesia in CRF patients having hemodialysis. Five patients dialyzed and five with normal renal function undergoing parathyroidectomy or thyroidectomy were anesthetized with sevoflurane (1.0%-2.5%) and nitrous oxide in oxygen. Serum and urine levels of F-, blood urea nitrogen (BUN), serum creatinine (Cr), serum and urine beta 2-microglobulin (BMG) levels, and urine N-acetyl-beta-D-glucosaminidase (NAG) level were measured. BUN, Cr, and serum and urine BMG levels were significantly higher in the CRF patients than in the controls. There were no differences in serum F- level, rate of elimination, and area under the curve of serum F- levels between the two groups. However, the CRF patients had a significantly lower level of urine F- than control subjects. These data suggest that the F- kinetics in the CRF patients is different from that in normal renal function subjects. This clinical study with a limited number of patients may facilitate further studies to define the mechanisms of differences in the F- kinetics between normal subjects and CRF patients having hemodialysis after sevoflurane anesthesia.

Inorganic Fluoride Kinetics and Renal Tubular Function After Sevoflurane Anesthesia in Chronic Renal Failure Patients Receiving Hemodialysis

Inorganic Fluoride Kinetics and Renal Tubular Function After Sevoflurane Anesthesia in Chronic Renal Failure Patients Receiving Hemodialysis