Trimetaphosphate Research Articles

Evaluation of the aesthetic effect, enamel microhardness and trans-amelodentinal cytotoxicity of a new bleaching agent for professional use containing trimetaphosphate and fluoride

This study evaluated the effects of calcium gluconate (CaGlu), sodium fluoride (NaF), sodium trimetaphosphate (TMP), and NaF/TMP when added to a 35% hydrogen peroxide (H2O2) bleaching gel on the color change, enamel hardness, penetration and cytotoxicity trans-amelodentinal. Bovine enamel/dentin disks (n = 288) were divided according to the bleaching gel: 35% H2O2; 35% H2O2 + 0.05% NaF; 35% H2O2 + 0.25% TMP; 35% H2O2 + 0.05% NaF + 0.25% TMP; 35% H2O2 + 0.1% NaF + 1% TMP and 35% H2O2 + 2% CaGlu. The bleaching gels were applied thrice (40 min/session) at 7-day intervals between each application. Then, the color change, percentage of surface hardness loss (%SH), cross-sectional hardness (ΔKHN), trans-amelodentinal penetration of H2O2, cell viability and morphology (MDPC-23 odontoblast-like cells), alkaline phosphatase activity (ALP) and deposition of mineralization nodules were determined. The data were submitted to ANOVA, followed by the Student-Newman-Keuls test (p < 0.05). All bleaching gels showed significant color changes after treatment (p < 0.001). Mineral loss (%SH and ΔKHN) and H2O2 penetration were lower for 35% H2O2/0.1% NaF/1% TMP; 35% H2O2/2% CaGlu, meanwhile, showed higher values, compared to the other groups (p < 0.001). Cell viability was around 9%, except for the bleaching gel containing 35% H2O2/0.1% NaF/1% TMP with 12.8% (p < 0.05). ALP was higher for groups containing TMP compared to other whitening gels (p < 0.05). The formation of mineralization nodules was greater for gels containing NaF/TMP or CaGlu (p < 0.05). The alterations of cell morphology were intense for all bleaching gels. It was concluded that the addition of NaF/TMP in-office bleaching did not interfere in bleaching efficacy, reduced enamel demineralization, H2O2 penetration and cytotoxicity.

Effects of Sodium Trimetaphosphate, Associated or Not with Fluoride, on the Composition and pH of Mixed Biofilms, before and after Exposure to Sucrose

The aim of the present study was to evaluate the influence of sodium trimetaphosphate (TMP), associated or not with fluoride (F), on the concentrations of F, calcium (Ca), and phosphorus (P) and on the pH of mixed biofilms of Streptococcus mutans and Candida albicans, before and after exposure to sucrose. The biofilms received three treatments (72, 78, and 96 h after the beginning of their formation), at three TMP concentrations (0.25, 0.5, or 1%), with or without F at 500 ppm. Solutions containing 500 and 1,100 ppm F as well as artificial saliva were also tested as controls. Biofilm pH was measured and the concentrations of F, Ca, and P were determined (solid and fluid phases). In a parallel experiment, after the third treatment (96 h), the biofilms were exposed to a 20% sucrose solution to simulate a cariogenic challenge and the pH of the medium, F, Ca, P, and TMP were determined. The data were submitted by two-way ANOVA, followed by Fisher’s least significant difference test (p < 0.05). Treatment with TMP and 500 ppm F led to higher F concentration in the biofilm fluid. Although TMP did not affect Ca concentrations, biofilms treated with TMP alone presented higher P concentrations. Treatment with 1% TMP and F led to the highest pH values of the biofilm, both before and after the cariogenic challenge. It was concluded that TMP increases F and P in the biofilm and that its presence promotes an increase in the pH of the medium, even after the cariogenic challenge.

Combined effect of casein phosphopeptide-amorphous calcium phosphate and sodium trimetaphosphate on the prevention of enamel demineralization and dental caries: an in vitro study.

To evaluate the effect of treatment with fluoridated toothpaste supplemented with a combination of sodium trimetaphosphate (TMP) and casein phosphopeptide-amorphous calcium phosphate (MI Paste Plus®) on the demineralization of dental enamel. Bovine enamel blocks selected by initial surface hardness (SHi) were randomly allocated into six groups (n = 12), according to the test toothpastes: (1) without F-TMP-MI Paste Plus® (Placebo); (2) 1100 ppm F (1100F); (3) MI Paste Plus®; (4) 1100F + MI Paste Plus® (1100F-MI Paste Plus), (5) 1100F + 3 % TMP (1100F-TMP); and (6) 1100F-TMP + MI Paste Plus® (1100F-TMP-MI Paste Plus). Blocks were treated two times per day with slurries of toothpaste (1 min), and groups 4 and 6 received an application of MI Paste Plus (3 min). Next, the samples were subjected to five pH cycles (demineralizing/remineralizing solutions) at 37 °C, to produce subsurface enamel lesions.Thereafter, the blocks were maintained for 2 days in fresh remineralizing solution. After pH cycling, the following were obtained: percentage of surface hardness loss (%SH); integrated loss of subsurface hardness (ΔKHN); profile analysis and lesion depth subsurface through polarized light microscopy (PLM); scanning electron microscopy (SEM); and fluoride (F), calcium (Ca), and phosphorus (P) in the enamel. The data were subjected to ANOVA (1-criterion), followed by the Student-Newman-Keuls test (p < 0.001). The 1100F-TMP-MI Paste Plus group showed better results for SHR, ΔKHN, and PLM (p < 0.001). The F concentration was similar among all groups (p > 0.001). The 1100F-TMP-MI Paste Plus group showed the highest concentration of Ca and P in the enamel (p < 0.001). The application of 1100F-TMP-MI Paste Plus promoted a higher inhibitory effect against enamel demineralization. The combination of treatments with F, TMP, and MI Paste Plus® can be an effective alternative to improve the oral health of individuals, especially those with high activity of dental caries and at high risk for its development.

Evaluation of new compositions of 10% hydrogen peroxide-based bleaching agents containing trimetaphosphate and fluoride on enamel demineralization.

This study evaluated the effect on enamel demineralization of 10% hydrogen peroxide (H2 O2 ) gels containing different concentrations of sodium trimetaphosphate (TMP) and sodium fluoride (NaF) combined with the daily use of fluoridated or placebo dentifrice. Bovine enamel blocks were selected by surface hardness (n=72) and randomly assigned to one of the following experimental treatments: 10% H2 O2 ; 10% H2 O2 +3% TMP+0.1% NaF; and 10% H2 O2 +0.3% TMP+0.05% NaF, each with or without fluoridated dentifrice. H2 O2 -based gels were applied for 30mind-1 followed by treatment with dentifrice (1min). Enamels blocks were stored in artificial saliva at 37°C between sessions during the 14days of experiment. Percentage of surface hardness loss (%SH) was calculated, and the blocks were cut into halves to analyze cross-sectional hardness (ΔKHN). Polarized light microscopy images were obtained of the longitudinal sections of the samples. Enamel treated with fluoridated dentifrice presented lower hardness loss than those treated with placebo dentifrice (%SH and ΔKHN). Use of TMP- and NaF-based gels, regardless of concentration, led to the lowest %SH values. Specimens treated with 10% H2 O2 gel had the highest %SH and ΔKHN values. Gels with 10% H2 O2 +3% TMP+0.1% NaF showed the lowest ΔKHN values. Microscopy images clearly showed that the addition of TMP and NaF to the H2 O2 -based gels was effective in reducing the loss of hardness, and the fluoridated dentifrice helped minimize it in all treatments.

Effect of daily use of fluoridated dentifrice and bleaching gels containing calcium, fluoride, or trimetaphosphate on enamel hardness: an in vitro study.

This study evaluated the effects of calcium gluconate (CaGlu), sodium fluoride (NaF), sodium trimetaphosphate (TMP), and NaF/TMP added to a 35% hydrogen peroxide (HP) bleaching gel for the reduction in enamel demineralization in vitro, with and without the use of a fluoridated dentifrice. Enamel blocks (n = 100) were obtained from bovine incisors (n = 200) after flattening and subjected to initial surface hardness (SH) analysis. The blocks were divided according to the bleaching gel (35% HP; 35% HP + 0.05% NaF; 35% HP + 0.25% TMP; 35% HP + 0.05% NaF + 0.25% TMP; 35% HP + 2% CaGlu) and were treated with ether non-fluoridated or fluoridated (1100ppm) dentifrice. The bleaching gels were applied thrice (40min/session) at the intervals of 7days between each application. After 21days, the final SH for the calculation of the percentage of SH loss (%SH) and cross-sectional hardness for the evaluation of the integrated hardness area (IH) were determined. Bleaching containing HP + NaF + TMP presented lowest %SH (p < 0.001), regardless of the dentifrice used. HP + NaF + TMP bleaching gel led to lower subsurface enamel mineral loss (IH) compared to the other groups (p < 0.001), and these did not differ from each other (p > 0.05). Daily use of fluoride dentifrice led to higher IH values (p < 0.001), regardless of the bleaching gels. The addition of NaF/TMP to a 35% HP bleaching gel remarkably reduced the mineral loss compared to the cases of the other bleaching gels, regardless of dentifrice. The association of TMP/NaF can be used as a strategy for reducing mineral loss during the bleaching procedure, even without the daily use of fluoride dentifrice.

Activity of sodium trimetaphosphate, associated or not with fluoride, on dual-species biofilms

This study aimed to evaluate the effect of sodium trimetaphosphate (TMP), either with fluoride (F) or without fluoride, on dual-species biofilms of Streptococcus mutans and Candida albicans. The 72 h biofilms were treated with 0.25%, 0.5%, or 1% TMP solutions, combined or not with 500 ppm F, and analysed by quantification of viable plate counts, metabolic activity, biomass, and extracellular matrix components. Biofilm structure was evaluated by scanning electron microscopy (SEM). TMP significantly reduced the number of S. mutans cells and biomass only when associated to F. Furthermore, fluoride-free TMP promoted significant reductions in biofilm metabolism, while all the tested solutions decreased the contents of the biofilm matrix compared to untreated groups. Regarding biofilm structure, TMP associated with F led to the formation of a less compact biofilm. It was concluded that TMP alone had a reducing effect, mainly on the metabolism and the extracellular matrix components of the biofilms.

Incorporation of chlorhexidine and nano-sized sodium trimetaphosphate into a glass-ionomer cement: Effect on mechanical and microbiological properties and inhibition of enamel demineralization

ObjectiveTo evaluate the antimicrobial/antibiofilm and mechanical properties, and the effect on enamel demineralization of a resin-modified GIC (RMGIC) containing CHX and nano-sized sodium trimetaphosphate (TMP). MethodsRMGIC was associated with CHX (1.25 or 2.5%) and/or TMP (7 or 14%). Antimicrobial and antibiofilm activity were assessed using agar diffusion test and evaluation of biofilm metabolism, respectively. In addition, fluoride (F) and TMP releases as well as the diametral tensile (DTS) and compressive (CS) strength were determined. The percentage of mineral loss (%SH), integrated loss of subsurface hardness (ΔKHN) and enamel F concentrations were also evaluated. ResultsRMGICs containing CHX associated or not with TMP presented higher inhibition zones and effect on S. mutans biofilm. A reduction on CS was observed only for RMGIC + 2.5%CHX and on DTS for RMGIC + 2.5%CHX + 14%TMP. The highest F and TMP releases and lowest %SH and ΔKHN values were detected for RMGIC + 1.25%CHX + 14%TMP and RMGIC + 2.5%CHX + 14%TMP. Higher enamel F concentrations were observed for TMP groups. Conclusion1.25%CHX and 14%TMP increased antimicrobial/antibiofilm action and the ability to prevent enamel demineralization, with minimal effect on the mechanical properties of RMGIC. Clinical significanceRMGIC containing CHX and TMP is an alternative material for patients at high risk for dental caries and can be indicated for low-stress regions or provisional restorations.

Development of Natural Gum Based Sustained Release Tablets of Propranolol hydrochloride

Objective: The objective of this work was to investigate the film coating potential of natural and modified, tamarind seed gum and fenugreek seed gum using propranolol HCl as model drug. Materials and Methods: Tamarind seed gum (TG), fenugreek seed gum (FG), sodium trimeta phosphate (STMP), propranolol HCl, hydroxypropyl methylcellulose (HPMC), sodium- alginate (SA). Core tablets of propranolol HCl were prepared and evaluated for weight, disintegration time, diameter, hardness, friability and disintegration time. The core tablets were coated using 2% w/v solution of TG, MTG, FG, MFG. The in-vitro release rate of drug from these coated tablets was compared to the release rate of drug from the tablets coated with 2% w/v of HPMC. Result: The tablets coated with natural and modified tamarind seed gum sustained the release of the drug up to 11hrs and 12hrs, respectively and natural and modified fenugreek seed gum sustained release of the drug up to 8hrs and 10 hrs respectively. The tablets coated with HPMC sustained release of the drug up to 14 hrs. The drug release profile of tablets coated with modified tamarind seed gum was comparable to the release profile of tablets coated with HPMC. Conclusion: On the basis of the release profile it is concluded that unmodified and modified TSG can be used as release rate controlling membrane.

Trimetaphosphate Activates Prebiotic Peptide Synthesis across a Wide Range of Temperature and pH.

The biochemical activation of amino acids by adenosine triphosphate (ATP) drives the synthesis of proteins that are essential for all life. On the early Earth, before the emergence of cellular life, the chemical condensation of amino acids to form prebiotic peptides or proteins may have been activated by inorganic polyphosphates, such as tri metaphosphate (TP). Plausible volcanic and other potential sources of TP are known, and TP readily activates amino acids for peptide synthesis. But de novo peptide synthesis also depends on pH, temperature, and processes of solvent drying, which together define a varied range of potential activating conditions. Although we cannot replay the tape of life on Earth, we can examine how activator, temperature, acidity and other conditions may have collectively shaped its prebiotic evolution. Here, reactions of two simple amino acids, glycine and alanine, were tested, with or without TP, over a wide range of temperature (0-100°C) and acidity (pH1-12), while open to the atmosphere. After 24h, products were analyzed by HPLC and mass spectrometry. In the absence of TP, glycine and alanine readily formed peptides under harsh near-boiling temperatures, extremes of pH, and within dry solid residues. In the presence of TP, however, peptides arose over a much wider range of conditions, including ambient temperature, neutral pH, and in water. These results show how polyphosphates such as TP may have enabled the transition of peptide synthesis from harsh to mild early Earth environments, setting the stage for the emergence of more complex prebiotic chemistries.

Sodium trimetaphosphate and hexametaphosphate impregnated with silver nanoparticles: characteristics and antimicrobial efficacy

This study aimed to synthesize and characterize materials containing silver nanoparticles (AgNP) with polyphosphates (sodium trimetaphosphate (TMP) or sodium hexametaphosphate (HMP), and evaluate their effect against Candida albicans and Streptococcus mutans. The minimum inhibitory concentration (MIC) was determined, which was followed by the quantification of the biofilm by counting colony-forming units (CFUs), the amount of metabolic activity, and the total biomass. The MICs revealed greater effectiveness of composites containing 10% Ag (TMP + Ag10% (T10) and HMP + Ag10% (H10)) against both microorganisms. It was observed that T10 and H10 reduced the formation of biofilms by 56–76% for C. albicans and by 52–94% for S. mutans for total biomass and metabolic activity. These composites promoted significant log reductions in the number of CFUs, between 0.45–1.43 log10 for C. albicans and 2.88–3.71 log10 for S. mutans (p < .001). These composites demonstrated significant antimicrobial activity, especially against S. mutans, and may be considered a potential alternative for new dental materials.

Cyclotriphosphate associated to fluoride increases hydroxyapatite resistance to acid attack.

This study evaluated the effect of sodium trimetaphosphate (TMP) associated or not with fluoride (F) on the structure and dissolution of carbonated hydroxyapatite (CHA). Synthetic CHA powder (1.0 g) was suspended in solutions containing TMP at 0-10%, associated with 0, 1100, 4500, or 9000 ppm F, and the precipitates were submitted to a pH cycle (n = 6/group). Samples were analyzed by Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction. F, calcium (Ca) and phosphorous (P) concentrations were determined in CHA, while P and F were analyzed in the supernatants. Data were submitted to analysis of variance, Student-Newman-Keuls' test and Pearson's correlation coefficient (α = 0.05). Solutions containing 1100 ppm F with TMP between 2-4% and 4500 and 9000 ppm F with TMP between 4 and 8% led to higher Ca/P ratio (p < 0.05) in CHA. Alkali-soluble F deposition was directly related to TMP concentrations whereas an inverse pattern was observed for acid-soluble F incorporation (p < 0.05). Greater P adsorption in the CHA structure was observed with increasing concentrations of TMP for the 0 and 1100 ppm F solutions (p < 0.05). All diffractograms and FTIR spectra showed a similar pattern to that for pure hydroxyapatite. Thus, when TMP and F are coadministered, TMP interferes with F deposition on CHA, and an ideal TMP:F ratio can enhance the precipitation of CHA with lower solubility. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 106B: 2553-2564, 2018.

Fluoride varnishes containing sodium trimetaphosphate reduce enamel demineralization in vitro

Objective: This study evaluated the effects of fluoride varnishes containing sodium trimetaphosphate (TMP) on bovine enamel demineralization in vitro.Material and methods: Enamel bovine discs were randomly assigned into six groups (n = 20/group): placebo, 2.5% NaF, 2.5% NaF/5% TMP, 5% NaF, 5% NaF/5% TMP, and a commercial formulation (Duraphat, 5% NaF). Varnishes were applied on all enamel discs and kept for 6 h. Loosely and firmly bound fluoride formed on/in enamel after treatment were analyzed in 10 discs from each group. The other 10 discs were subjected to a pH-cycling regimen for 7 days, and analyzed for surface (SH) and cross-sectional hardness (ΔKHN), as well as for loosely and firmly bound fluoride in/on enamel. Data were analyzed by analysis of variance (ANOVA) followed by Student–Newman–Keuls’ test (p < .05).Results: The lowest SH change and ΔKHN were observed for the 5%NaF/5%TMP varnish, which was significantly different from all the other groups. Both fluoridated varnishes containing TMP promoted significantly lower SH change and ΔKHN when compared with their counterparts without TMP. Loosely and firmly bound fluoride was significantly lower in groups treated with varnishes containing TMP.Conclusion: TMP and fluoride added to varnishes have a synergistic effect against enamel demineralization in vitro.

Effect of fluoride toothpaste with nano-sized trimetaphosphate on enamel demineralization: An in vitro study

ObjectiveThis study evaluated the effect of toothpastes containing 1100ppm F associated or not with micrometric or nano-sized sodium trimetaphosphate (TMP) on enamel demineralization in vitro, using a pH cycling model. DesignBovine enamel blocks (4mm×4mm, n=96) were randomly allocated into eight groups (n=12), according to the test toothpastes: Placebo (without fluoride or TMP); 1100ppm F (1100F); 1100F plus micrometric TMP at concentrations of 1%, 3% or 6%; and 1100F plus nanosized TMP at 1%, 3% or 6%. Blocks were treated 2×/day with slurries of toothpastes and submitted to a pH cycling regimen for five days. Next, final surface hardness (SHf), integrated hardness loss (IHL), differential profile of integrated hardness loss (ΔIHL) and enamel fluoride (F) concentrations were determined. Data were analyzed by ANOVA and Student-Newman-Keuls’ test (p<0.05). ResultsThe use of 1100F/3%TMPnano led to SHf 30% higher (p<0.001) and IHL∼80% lower (p<0.001) when compared to 1100F. This toothpaste also resulted in ∼64% reduction of mineral loss (ΔIHL) when compared to 1100F. Moreover, the addition of nano-sized TMP promoted increases in enamel F uptake of 90%, 160% and 100%, respectively for the concentrations of 1%, 3% and 6%, when compared to 1100F (p<0.001). ConclusionThe addition of nano-sized TMP at 3% to a conventional toothpaste significantly decreased enamel demineralization when compared to its counterparts without TMP or supplemented with micrometric TMP.

Protective Effect of Phosphates and Fluoride on the Dissolution of Hydroxyapatite and Their Interactions with Saliva

This study aimed to investigate the effect of phosphates and fluoride, alone or in combination, and the influence of salivary pellicle on hydroxyapatite (HA) dissolution. The baseline dissolution rate of HA discs was measured using a pH-stat system (0.3% citric acid, pH 3.2). In the first series of experiments, HA discs (n = 8/group) were treated with: a placebo solution (PLA, deionised water); sodium trimetaphosphate (TMP), sodium tripolyphosphate (TRI) and sodium pyrophosphate (PYRO) at 1 or 8%; 500 ppm F; 1,100 ppm F; 1,100 ppm F/1% TMP; 1,100 ppm F/8% TMP; 1,100 ppm F/1% TRI; 1,100 ppm F/8% TRI. In the second phase, HA discs were immersed in pooled human saliva (37°C/2 h) and treated with PLA, 1,100 ppm F/1% TMP, 1,100 ppm F/8% TMP, 1,100 ppm F/1% TRI, and 1,100 ppm F/8% TRI. After treatments, final dissolution rates were measured from 3 consecutive 30-min assays. Statistical analyses were performed using 2-way ANOVA followed by the Fisher test (α = 0.05). The type and concentration of phosphate tested significantly influenced HA dissolution; 8% TRI showed the highest reduction (36.9%) among all treatment solutions. Fluoride alone (1,100 ppm F) significantly reduced HA dissolution by 20.7%. When fluoride and phosphates were associated, 1,100 ppm F/1% TMP, 1,100 ppm F/8% TMP, and 1,100 ppm F/8% TRI showed the highest percentage reductions of dissolution (40.3-46.1%). Salivary pellicle led to a greater and more sustained protective effect of the treatment solutions compared to their counterparts without salivary coating. It was concluded that the association of phosphate and fluoride enhanced their protective effect against HA dissolution when compared with these compounds alone, especially in the presence of salivary pellicle.

Toothpaste with Nanosized Trimetaphosphate Reduces Enamel Demineralization.

This double-blind crossover study assessed the effects of a low-fluoride (low-F) dentifrice containing nanosized sodium trimetaphosphate (TMP) on enamel demineralization in situ. Nineteen subjects wore palatal appliances containing 4 blocks of bovine enamel and were randomly assigned to brush their teeth with placebo (without F/TMP), 250-ppm F (250F), 250F plus 0.05% nanosized TMP (250F-TMPnano), and 1,100-ppm F (1,100F) dentifrices during 7 d, under cariogenic challenge. Enamel surface hardness and cross-sectional hardness (ΔKHN [Knoop hardness number]), as well as F, calcium (Ca), and phosphorus (P) concentrations, were determined. Also, biofilm that formed on the blocks was analyzed for F, Ca, P, and insoluble extracellular polysaccharide concentrations. Data were submitted to analysis-of-variance models and Student-Newman-Keuls test ( P < 0.05). The 250F-TMPnano dentifrice promoted the lowest ΔKHN among all groups ( P < 0.001), while the percentage of surface hardness loss was similar to 1,100F. Also, similar F, Ca, and P concentrations in enamel were observed for 1,100F and 250F-TMPnano. In the biofilm, the highest F content was observed for 1,100F; Ca content was similar between 1,100F and 250F-TMPnano; and P content was similar among all groups. Similar extracellular polysaccharide values were observed for 250F-TMPnano and 1,100F ( P < 0.001), ionic activity of CaHPO40, CaF+, and HF0 ( P < 0.05) and degree of saturation of hydroxyapatite and CaF2 ( P < 0.05). It was concluded that the protective effect of 250F-TMPnano dentifrice was similar to a conventional dentifrice for most of the variables studied, having a more pronounced effect on the subsurface lesion when compared with the conventional toothpaste (1,100F). Knowledge Transfer Statement: Although toothpastes containing ≥1,000-ppm fluoride are more effective than low-fluoride formulations against dental caries, their early use can lead to side effects. This has prompted intensive research on alternatives to increase the anticaries effect of low-fluoride toothpastes. The present in situ study demonstrated that the addition of sodium trimetaphosphate nanoparticles to toothpastes containing 250-ppm fluoride significantly enhances the protective effect of this formulation against enamel demineralization to levels comparable to a 1,100-ppm fluoride toothpaste in terms of most of the variables studied. Most important, this formulation promoted the lowest loss of subsurface hardness among all groups, suggesting that caries lesions would take longer to develop under clinical conditions when compared with a conventional (1,100-fluoride) toothpaste.

Remineralizing Potential of a Low Fluoride Toothpaste with Sodium Trimetaphosphate: An in situ Study

Objective: To evaluate the effect of a low-fluoride (F) toothpaste supplemented with sodium trimetaphosphate (TMP) on enamel remineralization in situ. Design: Bovine enamel blocks were selected on the basis of their surface hardness (SH) after caries-like lesions had been induced, and randomly divided into 4 treatment groups, according to the toothpastes used: without F or TMP (placebo); 500 ppm F; 500 ppm F plus 1% TMP; and 1,100 ppm F. The study design was blinded and crossover and performed in 4 phases of 3 days each. Eleven subjects used palatal appliances containing 4 bovine enamel blocks which were treated 3 times per day during 1 min each time, with natural slurries of saliva and toothpaste formed in the oral cavity during toothbrushing. After each phase, the percentages of surface (%SH_R) and subsurface hardness recovery (%ΔKHN_R) were calculated. F, calcium (Ca), and phosphorus (Pi) contents in enamel were also determined. Data were analyzed by 1-way, repeated-measures ANOVA, followed by the Student-Newman-Keuls test (p < 0.05). Results: Toothpaste with 500 ppm F + TMP and 1,100 ppm F showed similar %SH_R and %ΔKHN_R as well as enamel F, Ca, and Pi concentrations. Conclusion: The addition of TMP to a low-fluoride toothpaste promoted a similar remineralizing capacity to that of a standard (1,100 ppm F) toothpaste in situ.

Fluoride and calcium concentrations in the biofilm fluid after use of fluoridated dentifrices supplemented with polyphosphate salts.

The present study evaluated fluoride (F) and calcium (Ca) concentrations in the biofilm fluid formed in situ under cariogenic challenge after using F dentifrices supplemented or not with sodium trimetaphosphate (TMP) or calcium glycerophosphate (CaGP). Volunteers (n=12) were randomly divided into 5 groups according to the toothpastes used: placebo (without F, CaGP or TMP), 1100ppmF (1100F) and low-fluoride dentifrice (LFD, 550ppmF) with no supplementation (550F) or supplemented with 1% TMP (550F-TMP) or 0.25% CaGP (550F-CaGP). In each phase, volunteers wore palatal appliances containing 4 bovine enamel blocks. Cariogenic challenge was performed with 30% sucrose solution, 6 times/day. On the morning of the eigth day, biofilm samples were collected 12h and 1h after brushing and cariogenic challenge. F and Ca analyses in the biofilm fluid were performed with the inverted electrode after buffering with TISAB III and using the Arsenazo III method, respectively. Data were submitted to two-way ANOVA (repeated measures) and Student-Newman-Keuls test (p<0.05). A dose-response relationship was verified between F concentrations in the dentifrices and in the biofilm fluid. Significant differences were observed among placebo, 550F, and 1100F only 1h after brushing, without statistical differences among 550F, 550F-TMP, and 550F-CaGP. No defined trend was observed among the groups regarding Ca concentrations, with the highest values seen for placebo and 550F-CaGP. The anticaries effect of LFDs supplemented with CaGP or TMP cannot be related to an increased availability of F and Ca in the biofilm fluid. The better performance of LFDs containing CaGP or TMP shown in previous studies should be attributed to their ability to interact with tooth enamel and with the biofilm, rather to their effect on the biofilm fluid.

Sodium trimetaphosphate enhances the effect of 250 p.p.m. fluoride toothpaste against enamel demineralization in vitro.

This in vitro study investigated the effect of sodium trimetaphosphate (TMP), added to toothpaste containing 250 p.p.m. fluoride, on enamel demineralization. Bovine enamel blocks (n = 96) were subjected to five pH cycles over a 7-d period and treatment with suspensions of toothpastes containing 0, 250, 500, and 1,100 p.p.m. fluoride (as sodium fluoride), as well as with 250 p.p.m. fluoride containing TMP at 0.25, 0.5, 1.0, and 3.0%. Treatment with toothpaste suspensions was performed under agitation twice a day, for 1 min. Surface and cross-sectional hardness, and fluoride firmly bound to enamel, were quantified. Data were subjected to one-way anova, followed by Tukey's test. Low-fluoride toothpastes containing TMP at 0.25-1.0% resulted in enamel mineral loss similar to that seen for the toothpaste containing 1,100 p.p.m. fluoride. Also, the addition of TMP to the toothpaste containing 250 p.p.m. fluoride promoted enamel fluoride concentrations similar to those obtained for the 500 p.p.m. fluoride group. The toothpaste containing 250 p.p.m. fluoride and 0.25% TMP led to the lowest mineral loss among all groups. It was concluded that the addition of as little as 0.25% TMP to a toothpaste containing 250 p.p.m. fluoride can reduce enamel demineralization to levels similar to those seen for a conventional toothpaste containing 1,100 p.p.m. fluoride, in vitro.

Anticaries effect of low-fluoride dentifrices with phosphates in children: A randomized, controlled trial

Low-fluoride dentifrices (LFD) have been recommended for young children aiming to minimize excessive fluoride intake during tooth brushing. Given the uncertainties surrounding the clinical efficacy of such formulations, alternatives to increase their anticaries effect have been investigated. ObjectivesThis double-blind, randomized controlled trial assessed the clinical efficacy of LFDs supplemented with Calcium Glycerophosphate (CaGP) or Sodium Trimetaphosphate (TMP) on the progression of dental caries in the deciduous dentition. MethodsChildren (average age 48 months old) from two Brazilian cities (Araçatuba and Fernandópolis) were randomly assigned into 3 groups, according to the dentifrice to be used: 500ppm F plus 1% TMP (“500TMP”, n=206), 500ppm F plus 0.25% CaGP (“500CaGP, n=201) and 1100ppm F (‘1100F’, n=193). Clinical exams (dmfs) were performed at baseline and 18 months after dentifrices started to be used, and the increment in the number of carious lesions (final dmfs – initial dmfs) was calculated. Data were analyzed by multivariate linear regression analysis to verify the influence of city, gender, previous caries experience and type of dentifrice on dmfs increment (p<0.05). ResultsMean caries increment observed for 500TMP (0.26) was significantly lower when compared with 1100F (0.74), while values found for 500CaGP (0.54) were not significantly different from 1100F. Caries increment was significantly higher in children from Araçatuba and in those with previous caries experience. ConclusionThe results indicate that clinical efficacy of LFDs supplemented with TMP is superior to that observed for a conventional formulation (1100F), while the addition of CaGP leads to similar efficacy when compared to 1100F. Clinical SignificanceChildren brushing with 500ppm F toothpastes containing phosphate salts developed fewer caries lesions when compared with those using a 1100ppm F dentifrice. The tested toothpastes can be regarded as a safe alternative to conventional formulations for children under 6 years of age, based on risk-benefit considerations.

Synthesis of Nucleoside Triphosphates from 2'-3'-Protected Nucleosides Using Trimetaphosphate.

Chemists have been attempting to triphosphorylate nucleosides and other alcohols using trimetaphosphate (TriMP) since the 1960s. However, this route appears to have been abandoned due to poor yields. The first practical syntheses of nucleoside triphosphates (NTPs) are reported using TriMP as the key reagent. This was achieved by reacting the tetrabutylammonium salt of TriMP with mesitylenesulfonyl chloride in the presence of DABCO in pyridine followed by the addition of an appropriately protected nucleoside and phthalimide. Quenching the reaction with aqueous buffer followed by hydrolysis of the OH protecting groups gave the NTPs in good yield.