Ppm Of Fluorine Research Articles

Knowledge of Brazilian Dental Students about the Use of Conventional Fluoride Dentifrices for Preschool Children from Zero to Six Years Old

Objective: To verify the knowledge of dental students about the correct use of fluoride dentifrices above 1000 pmm fluorine for children aged 0-6 years old. Material and Methods: This is a cross-sectional study in which self-administered questionnaires were administered to 355 dental students from sixth to ninth or tenth graduation period. The questionnaires included questions regarding knowledge of the need to use, concentration, amount, frequency and potential adverse effects of the use of conventional fluoride dentifrices above 1000 ppm of fluorine by children up to six years of age, as well as the mechanism of action and the method of using fluorides that has the most scientific evidence. A descriptive analysis of data was performed. Results: 83.1% of students reported receiving content on the use of fluoride dentifrices in early childhood. Most students consider the use of fluoride dentifrice as important for the age group from zero to three years (73.8%) and from three to six years (96.4%). Only 17.7% would indicate fluoride toothpaste above 1000 ppm fluoride for children from zero to three years and 40.6% for three to six years. 76.9% believe that the amount of ideal refers to a grain of rice (0-3 years) and 61.7% of pea grain (3-6 years). 43.4% of students believe that fluoride dentifrices as an adverse effect the potential to cause fluorosis independent of concentration. Conclusion: The students evaluated were misleading about the fluoride concentration of the dentifrices indicated for children up to six years of age; on the toxicity of fluorine; action mechanism of fluorides and the scientific method of greater scientific evidence on caries disease. Failures in training and need to update fluoride contents to be taught to future dentistry professionals are evident.

Experimental study of aluminum speciation in fluoride-rich supercritical fluids

The solubility of the albite-paragonite-quartz mineral assemblage was measured as a function of NaCl and fluorine concentration at 400°C, 500 bars and at 450°C, 500 and 1000 bars. Decreasing Al concentrations with increasing NaCl molality in F-free fluids of low salinity (mNaCl < 0.01) demonstrates that Al(OH)4− dominates Al speciation and is formed according to the reaction 0.5 NaAl3Si3O12H2(cr)+2 H2O = 0.5 NaAlSi3O8(cr)+Al(OH)4−+H+. Log K results for this reaction are −11.28 ± 0.10 and −10.59 ± 0.10 at 400°C, 500 bars and 450°C, 1000 bars, respectively. Upon further salinity increase, Al concentration becomes constant (at 400°C, 500 bars) or even rises (at 450°C, 1000 bars). The observed Al behavior can be explained by the formation of NaAl(OH)40(aq) or NaAl(OH)3Cl(aq)0. The calculated constant for the reaction Al(OH)4−+Na+=NaAl(OH)40(aq) expressed in log units is equal to 2.46 and 2.04 at 400°C, 500 bars and 450°C, 1000 bars, respectively. These values are in good agreement with the predictions given in Diakonov et al. (1996). Addition of fluoride at m(NaCl) = const = 0.5 caused a sharp increase in Al concentration in equilibrium with the albite-paragonite-quartz mineral assemblage. As fluid pH was also constant, this solubility increase indicates strong aluminum-fluoride complexation with the formation of NaAl(OH)3F(aq)0 and NaAl(OH)2F20(aq), according to 0.5 NaAl3Si3O12H2(cr)+Na++HF(aq)0+H2O = 0.5 NaAlSi3O8(cr)+ NaAl(OH)3F(aq)0+H+, log K = −5.17 and −5.23 at 400°C and 450°C, 500 bars, respectively, and 0.5 NaAl3Si3O12H2(cr)+Na++2 HF(aq)0 = 0.5 NaAlSi3O8(cr)+NaAl(OH)2F20(aq)+H+, log K = −2.19 and −1.64 at the same P-T conditions. It was found that temperature increase and pressure decrease promote the formation of Na-Al-OH-F species. Stability of NaAl(OH)2F20(aq) in low-density fluids also increases relative to NaAl(OH)3F(aq)0. These complexes, together with Al(OH)2F(aq)0 and AlOHF20(aq), whose stability constants were calculated from the corundum solubility measured by Soboleva and Zaraisky (1990) and Zaraisky (1994), are likely to dominate Al speciation in metamorphic fluids containing several ppm of fluorine.

Effect of sucrose-containing gum and fluoridated dentifrice on in situ remineralization of artificial caries

The aim of this study was to evaluate the remineralization of incipient carious lesions in bovine enamel in situ. Artificial carious lesions were produced and fixed in removable lower appliances in the region of the lingual surfaces of first molars, in six volunteers with ages between 18 and 22 years, who were subjected to 3 distinct experimental periods of 1 week each. In the first period (control group), patients brushed their teeth with a non-fluoridated dentifrice 4 times a day (after meals), and, in the second period (group I), patients used a dentifrice containing 1,500 ppm of fluorine (in the form of MFP). In the third period (group II) volunteers brushed their teeth with non-fluoridated dentifrice and used chewing gum containing 60% of sucrose during 20 minutes, 4 times a day (after meals). Before and after each treatment, the specimens underwent Vicker's hardness test (200 g of load), and the remineralization percentage (alpha) was calculated. The control group showed 2.78% of demineralization, and groups I and II showed 3.36 and 5.21% of remineralization, respectively. Statistical analysis (with Kruskal-Wallis and Miller's tests) showed significant difference (p < 0.05) between the control and experimental groups (I and II). Group II showed greater alpha than group I, but this difference was not significant. These results suggest that the use of sucrose-containing chewing gum and fluoridated dentifrice has a considerable effect on the remineralization of incipient carious lesions and may be a valuable alternative for their prevention.

Fluorosis dental: recuento de Streptococcus mutans en escolares provenientes de la Primera Región de Chile. Estudio longitudinal

Background: High fluorine concentrations in drinking water are associated with a decrease in the amount of salivary S mutants. Taking into account that clinical dental fluorosis can appear with 1.5 ppm of fluorine in the drinking water, fluorine concentration in Mamina is 2.4 ppm. Aim: To quantify salivary S mutans in school age children from Mamina, a zone with a high fluorine content in the drinking water, during one year. Material and methods: During 1997 and 1998, dental health was assessed and salivary samples were obtained from 51 children (27 male) aged 10 ± 2 years to quantify S mutans. Results: Most children studied had more than 105 salivary S mutans colony forming units. No changes in the rates of infection or dental health characteristics were observed during the observation year. Conclusions: High fluorine content in the drinking water did not have an effect on salivary S mutans infection in this population.

Scanning electron microscopical study on the fluorosis of enamel in rats.

Sixteen 28-day-old male rats of Wistar strain, with a mean body weight of 179 g, were divided into two equal groups. Each group of eight animals was maintained for 70 days on drinking water, ad lib., containing no fluorine (control group) and 100 ppm of fluorine (experimental group). All specimens examined were obtained from the incisal portions of the incisors. The following types of enamel specimens were prepared for scanning electron microscopy: (1) acid-etched specimens; (2) acid-etched specimens followed by low temperature microincineration; and (3) fractured specimens. The enamel formed during high fluoride exposure showed marked hypocalcification, that is, the crystallite density in the prism core and interprismatic region was lower than that of control animals. The organic substances appeared to increase in these regions. The changes were prominent in the outer and middle enamel layers. Such changes following fluoride administration appear to indicate an inhibition of enamel maturation, that is, an inhibition of the mineral deposition and/or an inhibition of organic matrix withdrawal.

Fluorite and fluorine in water

Abstract The content of fluorine in water in the neighbourhood of fluorite-containing mineralizations has been measured. The mineralizations contain skarn silicates, calcite, fluorite, scheelite and molybdenite. Increased contents were found both in streams and in ground water. The content in streams in the immediate neighbourhood of the mineralizations was found to be 0.3–0.5 ppm. The background value should be of the order of 0.15 ppm, provided that the fluorine is of atmospheric origin. In ground water, several ppm of fluorine have been measured. The anomalies in ground water seem to be restricted to an area close to the outcrops of the ore bodies. This is due to the reactivity of the fluoride ion, which makes it apt to be removed from solution.

Determination of small amounts of fluorine in the presence of aluminum, using the fluoride ion electrode

A new simple techique for the microdetermination of fluorine in the presence of aluminum was obtained by using the fluoride ion electrode. Procedures are as follows ;Aluminum fluoride complexes were deeomosed in alkali (pH>12) and the liberated aluminum was masked with oxine. The pH and total ionic strength were adjusted with TISAB, and fluorine determination was carried out with no extraction of the aluminum-oxine complex and free oxine.The calibration curve showed a linearity down to less than 0.1 ppm (5.3×1O-6M) of fluorine in the presence of 4 ppm of aluminum and oxine, which is as good as measurements obtained in the absence of aluminum.Recovery of 1 ppm of fluorine was relatively good-about 95%-, even in the presence of 200 ppm of aluminum. Good recovery of fluorine added to artificial cryolite was also found.

Determination of traces of organic fluorine in hydrocarbons

Organic samples containing down to 0.2 ppm of fluorine may be analysed by first converting the organic fluorine into inorganic fluoride by treatment with sodium biphenyl, followed by removal of diverse cations with a cation-exchanger before conductometric titration with lanthanum acetate. Effect of variables, sources of error, and control of reagent blanks are evaluated. For the 0.2-1 ppm organic fluorine level in synthetic blends made from 1-fluoronaphthalene, the relative estimated standard deviation was 7.8%; the mean relative error was 6.2 %. Based on the mean range from duplicate analyses of catalytically processed samples in the C(12) boiling range, at the 1 ppm fluorine level the estimated standard deviation was 0.087 ppm of fluorine. One analyst can determine the fluorine content of about 12 samples in 8 hr.

Studies on Fluorine and Other Related Material in the Rice : PartII. The fluorine contents of upland unpolished rice, lowland glutinous unpolished rice, unpolished rice for sake brewing and polished rice,

(1) The fluorine contents of 171 samples of lowland glutinous unpolished rice varied from 9.00-69.00ppm and averaged 22.947ppm. (2) Analysis of upland nonglutinous unpolished rice showed fluorine in 3.00-25.55ppm and upland glutinous unpolished rice contained from 10.00-42.33ppm. On the other hand 9.673ppm of fluorine were found in polished rice samples. (3) From these figures now obtained it was found that lowland rice had more fluorine than upland rice and that glutinous rice contained more fluorine than nonglutinous. (4) With the deterioration of quality the fluorine contents of rice samples varied to the smaller ones. (5) Nineteen samples of imported polished rice had the fluorine contents of 14.11ppm (non-glutinous short-grain rice produced in Australia)-115.84ppm (non-glutinous short-grain rice produced in Formosa).

Studies on Fluorine and Other Related Material in the Rice : Part 1. The fluorine content of lowland non-glutinous unpolished rice and its geographical correlation with mortality from gastric cancer

Through the courtesy of Food Management Training School, Mikawa-Ichinomiya, the author was able to determine of the fluorine content of 279 samples of lowland non-glutions unpolished rice from 38 prefectures of Japan in 1960. We are determinated of Aluminium-Hematoxylin method. The results obtained are as follows: (1) Two hundred and seventy-nine samples of lowland non-glutious unpolished rice averaged 19.963ppm of fluorine contained. (2) A comparison of different grades showed an increase of fluorine content with deterioration in quality. The smallest amount of fluorine were contained in first class rice samples, and the largest of fluorine in those of the fifth class rice samples. (3) A greater variation in the fluorine contents ws by locality than by variety. The rice samples from Nara and Niigata Prefecture, cancerous districts, contained nearly sextuple as much fluorine as those of the southern Kyushu, particularly in Kagoshima Prefec., non-cancercus distirict. (4) There was a positive correlation at 0.1 % for the level of significance between the fluorine contents and male corrected death rate from gastric cancer in Japan, in 1960, the correlation coefficient being +0.615 of 38 drefectures, and a correration between the contents and female corrected death rate was found positive at the high level of significance.

FLUORINE CONTENT AND TOTAL HARDNESS OF MUNICIPAL WATER SUPPLY IN HUNDRED AND TWO CITIES IN JAPAN

Fluorine contents and total hardnesses of municipal water supply in 102 principal cities in Japan were determined by SPADNS-zirconium method and EDTA method.1) Fluorine contents of water ranged generally from 0.05 to 0.2 ppm. Cities with common water supply containing over 0.2 ppm of fluorine were; Kumamoto (0.23), Toyonaka (0.27), Tsushima (0.29), Takarazuka (0.32), Kyoto (0.62-experimentally fluoridated-Yamashina area) and Kasaoka (1.2-1.3 ppm).2) Total hardnesses of water (expressed as CaCO3) ranged generally from 40 to 100 ppm; most of them appeared to belong to soft water. In some cities, total hardnesses were above 250 ppm, e. g. Mobara (256.7) and Kasaoka (280.3ppm). Itoigawa was supplying moderately hard water (184.1 ppm) and there were eleven other cities distributing slight hard water (100-150 ppm).

牛の地方性弗素中毒症 とくにその斑状歯について

1. In areas where fluorosis has become enzootic, cattle ingest fluorine from drinking water rich in fluorides. In general, feed contain from 2 to 30 ppm of natural fluorine.2. Development of mottled teeth in cattle varies with ingestion levels, age at the time of ingestion; duration of ingestion, individuality, etc. It seems that mottled teeth come out through the ingestion of at least 0.5 to 0.6ppm of fluorine contained in drinking water.3. Mottled teeth were observed in about 50 per cent of calves drinking water containing from 0.6 to 5.0 ppm of fluorine in the stage of development of permanent teeth.4. Many cattle with mottled teeth were auscultated with abnormal cardiac sounds-splitting and doubling-more frequently than cattle with normal teeth.5. The amount of fluorine excreted in the urine reflected relative levels of fluorine ingested. Fluorine contents in the urine were higher in cattle absorbing an excessive amount of fluoride than in normal cattle. Fluorine contents up to 5 ppm are normal.6. The areas where fluorosis is enzootic have no relations to so-colled “Kuwazu” or “Kuiyami” disease, or anoretic disease, of cattle.7. Calves raised in fluorosis prevailing areas are often found to have mottled teeth.

Control of Dental Caries by the Addition of Fluorides to Public Water Supplies

During the past 12 years a mass of epi­ demiologic evidence has been accumu­ lated which indicates that where fluo­ rine is naturally present in public water supplies the prevalence of caries is less by 60 per cent in permanent teeth. This evidence likewise demonstrates that fluo­ rine is the active caries inhibiting fac­ tor in domestic water supplies, and that the maximum protection is obtained at about 1 ppm, at which level objection­ able dental fluorosis is eliminated. Sur­ veys by Dean2 and associates were the first to show that children in the 12 to 14 year age group, who, since birth, had consumed water containing 1 ppm of fluorine had only one-third the amount of dental decay that children had who consumed fluorine-free domestic water. Hardgrove and Bull3 demonstrated the effect of fluorine in reducing the inci­ dence of dental caries in the deciduous teeth. McKay and Frisch4 demonstrated that the beneficial effects of drinking fluoride water during the period of tooth calcification continue through adult life. Armstrong and Brekhus5 showed that the carious tooth contains less fluorine than does the noncarious tooth. Investigation6 has shown that fluorine has the same action on experimental ani­ mals in reducing tooth decay that it has on humans. Animal research likewise shows that artificially added fluorides produce exactly the same effect as fluo­ rides naturally present in water. McClure7 has shown that no toxic ef­ fects from the ingestion of fluorides in drinking water, containing as high as 5.5 ppm, can be found, other than mottled enamel. When it is realized that approxi­ mately 8,000,000 people in the United States have consumed water containing from 1 to 27 ppm throughout their life, it can be assumed that the medical pro-