Calcium Trimetaphosphate-Loaded Electrospun Poly(Ester Urea) Nanofibers for Periodontal Tissue Engineering.

The objective of this research was to create and appraise biodegradable polymer-based nanofibers containing distinct concentrations of calcium trimetaphosphate (Ca-TMP) for periodontal tissue engineering. Poly(ester urea) (PEU) (5% w/v) solutions containing Ca-TMP (15%, 30%, 45% w/w) were electrospun into fibrous scaffolds. The fibers were evaluated using SEM, EDS, TGA, FTIR, XRD, and mechanical tests. Degradation rate, swelling ratio, and calcium release were also evaluated. Cell/Ca-TMP and cell/scaffold interaction were assessed using stem cells from human exfoliated deciduous teeth (SHEDs) for cell viability, adhesion, and alkaline phosphatase (ALP) activity. Analysis of variance (ANOVA) and post-hoc tests were used (α = 0.05). The PEU and PEU/Ca-TMP-based membranes presented fiber diameters at 469 nm and 414-672 nm, respectively. Chemical characterization attested to the Ca-TMP incorporation into the fibers. Adding Ca-TMP led to higher degradation stability and lower dimensional variation than the pure PEU fibers; however, similar mechanical characteristics were observed. Minimal calcium was released after 21 days of incubation in a lipase-enriched solution. Ca-TMP extracts enhanced cell viability and ALP activity, although no differences were found between the scaffold groups. Overall, Ca-TMP was effectively incorporated into the PEU fibers without compromising the morphological properties but did not promote significant cell function.

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 30 min d-1 followed by treatment with dentifrice (1 min). Enamels blocks were stored in artificial saliva at 37°C between sessions during the 14 days 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 Fluoride Toothpaste Containing Nano-Sized Sodium Hexametaphosphate on Enamel Remineralization: An in situ Study.

OBJECTIVE: To evaluate the remineralizing potential of a conventional toothpaste (1,100 ppm F) supplemented with nano-sized sodium hexametaphosphate (HMPnano) in artificial caries lesions in situ. DESIGN: This double-blinded crossed study was performed in 4 phases of 3 days each. Twelve subjects used palatal appliances containing 4 bovine enamel blocks with artificial caries lesions. Volunteers were randomly assigned into the following treatment groups: no F/HMP/HMPnano (Placebo); 1,100 ppm F (1100F); 1100F plus 0.5% micrometric HMP (1100F/HMP) and 1100F plus 0.5% nano-sized HMP (1100F/HMPnano). Volunteers were instructed to brush their natural teeth with the palatal appliances in the mouth for 1 min (3 times/day), so that blocks were treated with natural slurries of toothpastes. After each phase, surface hardness post-remineralization (SH2), integrated recovery of subsurface hardness (ΔIHR), integrated mineral recovery (ΔIMR) and enamel F concentration were determined. Data were submitted to analysis of variance and Student-Newman-Keuls' test (p < 0.001). RESULTS: Enamel surface became 42% harder when treated with 1100F/HMPnano in comparison with 1100F (p < 0.001). Treatment with 1100F/HMP and 1100F/HMPnano promoted an increase of ∼23 and ∼87%, respectively, in ΔIHR when compared to 1100F (p < 0.001). In addition, ΔIMR for the 1100F/HMPnano was ∼75 and ∼33% higher when compared to 1100F and 1100F/HMP respectively (p < 0.001). Enamel F uptake was similar among all groups except for the placebo (p < 0.001). CONCLUSION: The addition of 0.5% HMPnano to a conventional fluoride toothpaste was able to promote an additional remineralizing effect of artificial caries lesions.

Effects of Acetone Fraction From Buchenavia tomentosa Aqueous Extract and Gallic Acid on Candida albicans Biofilms and Virulence Factors.

A promising anti-Candida activity of Buchenavia tomentosa extracts was recently described. In the present work, experiments were carried out to determine the fraction with higher antifungal activity from a B. tomentosa extract. Acetone fraction (AF) was obtained from the aqueous extract from dried leaves (5 min/100°C) and it was the most effective one. Gallic acid (GA) was identified by electrospray ionization mass spectrometry (ESI-MS) and also chosen to perform antifungal tests due to its promising activity on Candida albicans. Minimal inhibitory and fungicidal concentrations (MIC and MFC) were determined by broth microdilution technique. The effect on virulence factors of C. albicans was evaluated, and the cytotoxicity was determined. MIC50 and MIC90 values were both equal to 0.625 mg ml-1 for AF and 2.5 and 5 mg ml-1, respectively, for GA. AF and GA showed ability to inhibit C. albicans adherence and to disrupt 48 h-biofilm. AF and GA were effective in reducing the formation of hyphae of C. albicans SC5314. AF and GA decreased adherence of C. albicans to oral epithelial cells. AF and GA showed slight to moderate toxicity to Vero cells. This result suggests further studies for topic use of these compounds. AF, which contains a combination of several molecules, presented greater potential of antimicrobial activity than GA, with lower values of MIC and lower cytoxicity.

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.

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.

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 (%SHR) and subsurface hardness recovery (%ΔKHNR) 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 %SHR and %ΔKHNR 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.

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.

Effectiveness of a Toothpaste with Low Fluoride Content Combined with Trimetaphosphate on Dental Biofilm and Enamel Demineralization in situ.

OBJECTIVE: The aim of the present study was to evaluate in situ whether a toothpaste with low fluoride associated with sodium trimetaphosphate (TMP) would provide similar effect to that of a 1,100 ppm F toothpaste. DESIGN: This crossover double-blind study consisted of 4 phases (14 days each), during which 10 volunteers wore oral appliances containing 4 enamel bovine blocks. The cariogenic challenge was performed by the application of a 20% sucrose solution (6×/day). The toothpaste treatments (2×/day) were: placebo, 500 ppm F, 500 ppm F plus 1% TMP, and 1,100 ppm F. At the end, enamel mineral loss and biofilm composition were analyzed. RESULTS: The toothpaste with 500 ppm F plus 1% TMP showed the lowest mineral loss (p < 0.05). Regarding the fluoride and calcium concentrations in the enamel and in the biofilm, there were no significant differences between 500 ppm F plus 1% TMP, and 1,100 ppm F toothpastes (p > 0.569), but they were significantly different when compared to toothpaste with 500 ppm F (p < 0.050). CONCLUSION: The addition of 1% TMP to a low-fluoride toothpaste reduces enamel demineralization in situ similar to a 1,100 ppm F toothpaste.

Longitudinal evaluation of fluoride levels in nails of 18-30-month-old children that were using toothpastes with 500 and 1100 µg F/g.

OBJECTIVES: This study aimed to evaluate the fluoride concentration in the fingernails and toenails of children aged 18-30 months during use of fluoride-containing toothpastes supplemented with calcium glycerophosphate (CaGP) or sodium trimetaphosphate (TMP). METHODS: According to the toothpaste used, children (n = 56) were randomly assigned into three groups: 500 µg F/g with 1% TMP, 500 µg F/g with 0.25% CaGP, and 1100 µg F/g. Fingernails and toenails were collected monthly over a period of 330 days, from the beginning of toothpaste use. Fluoride concentration in the water consumed by the volunteers and fluoride intake from diet and toothpaste were also determined. Fluoride analyses were performed with the electrode after hexamethyldisiloxane-facilitated diffusion or by the direct method, according to the samples. Data passed normality and homoscedasticity tests and were analyzed by 2-way analysis of variance (anova) and 1-way anova followed by Student-Newman-Keuls test (P < 0.05). RESULTS: Fluoride levels in the fingernails and toenails as well as fluoride intake from toothpaste were similar for the groups treated with 500 µg F/g with 1% TMP and 500 µg F/g with 0.25% CaGP toothpastes, but significantly lower than the 1100 µg F/g group (P < 0.05). No significant differences were noted among the groups regarding fluoride intake from diet and that by water consumed by the volunteers (P > 0.05). CONCLUSION: The results of the longitudinal study suggest that the level of fluoride present in nails was lower with the use of toothpastes with a low fluoride concentration.

The effect of chronic treatment with fluoride on salivary activity, tooth, and bone in spontaneously hypertensive rats (SHR).

The present study evaluated the effect of chronic treatment with sodium fluoride on salivary activity, tooth, and bone in spontaneously hypertensive rats (SHR). The treatment was made with a 20-ppm NaF solution added to the drinking water for 30 days. Systolic blood pressure values were obtained by plethysmography; fluoride concentration was determined by an ion-selective electrode; calcium concentration and amylase activity were determined by commercial kits; and enamel microhardness was verified by longitudinal section. Systolic blood pressure values and animals' weight were not changed by treatment. However, the salivary flow rate-which was lowered in SHR at baseline when compared to Wistar rats-was found to be increased with the treatment with NaF. The fluoride concentration was increased in the plasma of the treated groups, even though it remained lower for the treated SHR in relation to the treated Wistar rats. Calcium concentration was decreased in the saliva and plasma of SHR treated with NaF. A reduction in the plasmatic total protein concentration was observed in SHR treated with NaF. The fluoride concentration on bone surface was found to be increased in Wistar or SHR treated with NaF. In treated SHR's femurs, it was observed a significant reduction in fluoride concentrations. Enamel microhardness of the incisor teeth was not changed by the treatment with NaF in both groups. The distribution of fluoride to the salivary glands in SHR is poor, and treatment with NaF causes a decrease in the concentration of important biochemical parameters to the salivary physiology in SHR.

Differences in loosely bound fluoride formation and anticaries effect of resin-based fluoride varnishes.

OBJECTIVE. Our in vitro study evaluated calcium fluoride formation in enamel and the anticaries effect of seven resin-based varnishes under cariogenic challenge. METHODS. Enamel blocks were subjected to pH cycling. The experimental groups received fluoride varnish application, the positive control received topical fluoride gel treatment, and the negative control did not receive any treatment. The pH cycling surface hardness (SH1 ) and integrated loss of subsurface hardness (ΔKHN) were then determined. We measured the amount of fluoride released into the demineralizing and remineralizing (DE-RE) solutions used in pH cycling. The fluoride concentration in the enamel was determined 24 h after application of the products as loosely bound fluoride and firmly bound fluoride. RESULTS. Higher deposits of loosely bound fluoride were observed for Duofluorid, followed by Biophat. For Duraphat, Bifluorid, Duraflur, and Duofluorid, no difference was observed in the SH1 and ΔKHN values, with the lowest mineral loss compared to the other groups. The Bifluorid and Duofluorid groups released high fluoride amounts into the DE-RE, and statistically significant difference was noted between them. CONCLUSIONS. The anticaries effect showed no correlation with higher deposited fluoride amounts, resin type, or fluoride source.

Spontaneously hypertensive rat as experimental model of salivary hypofunction.

OBJECTIVE: To analyse the salivary activity in spontaneously hypertensive rats (SHRs) evaluating biochemical parameters of saliva in 4-week-old and 12-week-old animals. DESIGN: Systolic blood pressure (SBP) was recorded by tail plethysmography. The salivary flow rate was stimulated by pilocarpine (SFR). The pH and salivary buffering capacity (SBC) were evaluated with a specific electrode. The concentrations of fluoride ([F(-)]) and calcium ([Ca(++)]) ions were determined using an electrode connected to a calibrated ion analyser. The total protein concentration was determined by Lowry method, and amylase activity by kinetic method. The salivary IgA was determined by enzyme-linked immunosorbent assay (ELISA). RESULTS: The SFR, [F(-)] and [Ca(++)] increased with age in normotensive rats, however no alteration in pH, total protein and IgA was observed between 4 and 12 weeks old Wistar rats. SBC decreased with age in Wistar rats. The SFR was not altered between SHRs in different ages and it was lower in 12 weeks old SHR when compared to Wistar rats. An increase in the protein concentration, and in the amylase activity and [F(-)] was observed with the development of SHR. Unaltered SBC, salivary IgA and [Ca(++)] were observed in 12 weeks old when compared to 4 weeks old SHR. The [Ca(++)] ions were reduced in saliva of SHR than that of Wistar rats at 12 weeks. A lower pH was observed in saliva of Wistar than that of SHR at 12 weeks. CONCLUSIONS: SHR is an experimental model of salivary hypofunction, the decreased SFR observed in SHR at different ages was associated to salivary biochemical parameter alterations.

Atenolol reduces salivary activity in pups of spontaneously hypertensive and normotensive rats treated during pregnancy and lactation.

The salivary activity in pups of spontaneously hypertensive rats (SHR) and Wistar (W) rats treated with atenolol during pregnancy, and lactation was evaluated. Atenolol's anti-hypertensive effect on the SHR rats was noticed from the beginning of treatment. Atenolol-treated SHR and Wistar rat pups showed a decrease in salivary gland weight, salivary flow, and protein concentration, with no alteration in salivary amylase activity. Atenolol's effect on salivary glands can interfere with oral health maintenance.

Fluoride release/recharge from restorative materials--effect of fluoride gels and time.

This study examined the differences in fluoride release and recharge among four restorative materials following treatment with APF or neutral fluoride gel for one or four minutes. Specimens were immersed in 2 mL of deionized water, while fluoride release was measured at 24-hour intervals for 15 days using an ion-selective electrode and analyzer. The materials were then treated with the fluoride gels. The fluoride release was measured for 15 days. ANOVA (p<0.05) showed higher fluoride release for Ketac-Fil before fluoride application and for Vitremer and Fuji II LC after application of APF gel. APF gel yielded higher fluoride release when compared to neutral gel, regardless of the material. Fluoride recharge and release was greater after the four-minute APF gel application, with no difference between the times of application for the neutral gel (p>0.05), except for Ketac-Fil. The pattern of release before and after application of the gels was similar and was higher at day 16 compared to day one for the APF gel for resin materials, with higher release at day 15 compared to the initial for Fuji II LC and Vitremer. It was concluded that RM-GICs were the most effective materials with regards to fluoride release after application of APF gel for four minutes.