Synergistic effect between plant extracts and fluoride to protect against enamel erosion: An in vitro study.

Polyphenol-rich solutions, such as plant extracts and teas, can modify the salivary pellicle and improve the protection against dental erosion. In this study, we further explored how these polyphenol-rich plant extracts solutions behave in the presence of fluoride. We distributed enamel specimens into 9 groups (n = 15): Control_No_F- (Deionized water); Control_F- (500 ppm F-), Grape_Seed_No_F- (Grape seed extract), Grape_Seed_F- (Grape seed extract + 500 ppm F-), Grapefruit_Seed_No_F- (Grapefruit seed extract), Grapefruit_Seed_F- (Grapefruit seed extract + 500 ppm F-), Blueberry_No_F- (Blueberry extract), Blueberry_F- (Blueberry extract + 500 ppm F-), and Sn2+/F-_Rinse (commercial solution containing 800 ppm Sn2+ and 500 ppm F-). The specimens were submitted to 5 cycles (1 cycle per day), and each cycle consisted of: salivary pellicle formation (human saliva, 30 min, 37°C), modification of the pellicle (2 min, 25°C), pellicle formation (60 min, 37°C), and an erosive challenge (1 min, citric acid). Between cycles, the specimens were kept in a humid chamber. Relative surface hardness (rSH), relative surface reflection intensity (rSRI) and calcium released to the acid were analysed, using general linear models, and Kruskal-Wallis with post-hoc Dunn's tests. We observed that the presence of fluoride in synergy with the extract solutions provided better protection than the groups containing extract or fluoride only. For rSH, we observed a significant main effect of extracts (F(4,117) = 9.20; p<0.001) and fluoride (F(1,117) = 511.55; p<0.001), with a significant interaction (F(3,117) = 6.71; p<0.001). Grape_Seed_F- showed the best protection, better than fluoride, and Sn2+/F-_Rinse. Calcium results also showed greater protection for the groups containing fluoride, whereas for rSRI, despite a significant interaction between extract and fluoride (F(3,117) = 226.05; p<0.001), the differences between the groups were not as clearly observed. We conclude that polyphenols from plant extracts, when combined with fluoride, improve the protective effect of salivary pellicles against enamel erosion

Rinsing solutions containing natural extracts and fluoride prevent enamel erosion in vitro

Polyphenols interact with salivary proteins and thus can improve the pellicle’s erosion protective properties. This effect could be exploited to create rinsing solutions with polyphenols as active ingredients for erosion prevention. Different from the current gold standard for erosion protective rinsing solutions, these rinses would not rely on stannous ions. This would offer alternatives for patients with concerns regarding the composition of rinsing solutions and preferring bio-products. Objective: To develop an erosion-preventive rinsing solution containing natural polyphenol-rich extracts. Methodology: Solutions were prepared with polyphenols from either grapeseed extract or cranberry extract, 500 ppm fluoride added, and additionally flavors and sweeteners. Controls were deionized water, 500 ppm fluoride solution, and the gold standard rinse in the field (Sn2+/F-). In total, 135 enamel specimens (n=15/group) were subjected to five cycles of salivary pellicle formation (30 min, 37°C), modification with the solutions (2 min, 25°C), further salivary pellicle formation (60 min, 37°C), and erosive challenge (1 min, 1% citric acid, pH 3.6). Relative surface microhardness (rSMH), surface reflection intensity (rSRI), and amount of calcium release (CaR) were investigated. Data were analyzed with Kruskal-Wallis and Wilcoxon rank sum tests (α=0.05). Results: The polyphenol solutions containing fluoride, as well as additional flavors, protected enamel better than fluoride alone, and similar to the Sn2+/F- solution, when investigating both rSMH and CaR. When measuring rSRI, Sn2+/F- showed the best protection, while the polyphenol solutions were similar to fluoride. Conclusion: For two of the three assessed parameters (rSMH and CaR), both developed polyphenol-rich rinsing solutions were able to protect enamel from erosion, improving/potentializing the effect of fluoride and matching the protection offered by the current gold standard rinsing solution

Rinsing solutions containing natural extracts and fluoride prevent enamel erosion in vitro.

BACKGROUND Polyphenols interact with salivary proteins and thus can improve the pellicle's erosion protective properties. This effect could be exploited to create rinsing solutions with polyphenols as active ingredients for erosion prevention. Different from the current gold standard for erosion protective rinsing solutions, these rinses would not rely on stannous ions. This would offer alternatives for patients with concerns regarding the composition of rinsing solutions and preferring bio-products. OBJECTIVE To develop an erosion-preventive rinsing solution containing natural polyphenol-rich extracts. METHODOLOGY Solutions were prepared with polyphenols from either grapeseed extract or cranberry extract, 500 ppm fluoride added, and additionally flavors and sweeteners. Controls were deionized water, 500 ppm fluoride solution, and the gold standard rinse in the field (Sn2+/F-). In total, 135 enamel specimens (n=15/group) were subjected to five cycles of salivary pellicle formation (30 min, 37°C), modification with the solutions (2 min, 25°C), further salivary pellicle formation (60 min, 37°C), and erosive challenge (1 min, 1% citric acid, pH 3.6). Relative surface microhardness (rSMH), surface reflection intensity (rSRI), and amount of calcium release (CaR) were investigated. Data were analyzed with Kruskal-Wallis and Wilcoxon rank sum tests (α=0.05). RESULTS The polyphenol solutions containing fluoride, as well as additional flavors, protected enamel better than fluoride alone, and similar to the Sn2+/F- solution, when investigating both rSMH and CaR. When measuring rSRI, Sn2+/F- showed the best protection, while the polyphenol solutions were similar to fluoride. CONCLUSION For two of the three assessed parameters (rSMH and CaR), both developed polyphenol-rich rinsing solutions were able to protect enamel from erosion, improving/potentializing the effect of fluoride and matching the protection offered by the current gold standard rinsing solution

Estimation and Prediction of Solar Wind Propagation from L1 Point to Earth’s Bow Shock

Having precise knowledge of the near-Earth solar wind (SW) and the embedded interplanetary magnetic field (IMF) is of critical importance to space weather operation due to the usage of SW and IMF in almost all magnetospheric and ionospheric models. The most widely used data source, OMNI, propagates SW properties from Lagrangian point L1 to the Earth’s bow shock by estimating the propagation time of the SW. However, the time difference between OMNI timeshifted IMF and the best match-up of IMF can reach ˜15 min. Firstly, we aim to develop an improved statistical algorithm to contribute to the SW propagation delay problem of space weather prediction. The algorithm focuses on matching SW features around the L1 point and upstream of the bow shock by computing the variance, cross-correlation coefficient, the plateau-shaped magnitude index, and the non-dimensional measure of average error index between the measurements at the two locations. The obtained propagation times are then compared to OMNI. Factors that limit the OMNI accuracy are also examined. Secondly, the automatic algorithm allows us to generate large sets of input and target variables using multiple spacecraft pairs at L1 and near-Earth locations to train, validate, and test machine learning models to specify and forecast near-Earth SW conditions. Finally, we offer a machine learning (ML) approach to specify and predict the propagation time from L1 monitors to a given location upstream or at the bow shock and forecast near-Earth SW conditions with the gradient boosting and random forest prediction models in the form of an ensemble of decision trees

Estimation and Prediction of Solar Wind Propagation from L1 Point to Earth’s Bow Shock

Having precise knowledge of the near-Earth solar wind (SW) and the embedded interplanetary magnetic field (IMF) is of critical importance to space weather operation due to the usage of SW and IMF in almost all magnetospheric and ionospheric models. The most widely used data source, OMNI, propagates SW properties from Lagrangian point L1 to the Earth’s bow shock by estimating the propagation time of the SW. However, the time difference between OMNI timeshifted IMF and the best match-up of IMF can reach ˜15 min. Firstly, we aim to develop an improved statistical algorithm to contribute to the SW propagation delay problem of space weather prediction. The algorithm focuses on matching SW features around the L1 point and upstream of the bow shock by computing the variance, cross-correlation coefficient, the plateau-shaped magnitude index, and the non-dimensional measure of average error index between the measurements at the two locations. The obtained propagation times are then compared to OMNI. Factors that limit the OMNI accuracy are also examined. Secondly, the automatic algorithm allows us to generate large sets of input and target variables using multiple spacecraft pairs at L1 and near-Earth locations to train, validate, and test machine learning models to specify and forecast near-Earth SW conditions. Finally, we offer a machine learning (ML) approach to specify and predict the propagation time from L1 monitors to a given location upstream or at the bow shock and forecast near-Earth SW conditions with the gradient boosting and random forest prediction models in the form of an ensemble of decision trees

Identification and quantification of cannabinoids in hemp-containing teas by HPLC-HRMS

In dieser Arbeit wurde die Entwicklung eines neuen Extraktionsverfahrens für Cannabinoide in Aufgüssen von hanfhaltigen Teeerzeugnissen beschrieben. Es wurden Aufgüsse, welche ausschließlich durch den Zusatz von Wasser hergestellt wurden und Aufgüsse, welche durch den Zusatz von fetthaltigen Zutaten wie Sahne und Speiseöl hergestellt wurden, betrachtet. Des Weiteren wurde der Einfluss fetthaltiger Komponenten auf die in hanfhaltigen Tees enthaltenen Cannabinoide Δ9-Tetrahydrocannabinol und Δ9-Tetrahydrocannabinol-9 -Carbonsäure A untersucht

Salivary pellicle modification with polyphenol-rich teas and natural extracts to improve protection against dental erosion.

OBJECTIVE To investigate the modification of the salivary pellicle with different polyphenol-rich teas and natural extracts for the protection against dental erosion. METHODS We performed two experiments: one with teas (Green tea, Black tea, Peppermint tea, Rosehip tea, negative control [NC]) and other with natural extracts (Grape seed, Grapefruit seed, Cranberry, Propolis, NC), where NC was deionized water. A total of 150 enamel specimens were used (n = 15/group). Both experiments followed the same design, consisting of 5 cycles of: salivary pellicle formation (30 min, 37 °C), modification with the solutions (30 min, 25 °C), further salivary pellicle formation (60 min, 37 °C) and erosive challenge (1 min, 1% citric acid, pH 3.6). Relative surface microhardness (rSMH), relative surface reflection intensity (rSRI) and amount of calcium release (CaR) were evaluated. Data were analysed with Kruskal-Wallis and Wilcoxon rank sum tests with Bonferroni correction (α = 0.05). RESULTS Regarding teas, Black and Green teas showed the best protection against dental erosion, presenting higher rSMH and lower CaR than NC. Peppermint tea was not different to NC and Rosehip tea caused erosion, showing the highest CaR and greatest loss of SMH and SRI. Regarding natural extracts, Grape seed and Grapefruit seed extracts presented the best protective effect, with significantly higher rSMH and lower CaR. Cranberry caused significantly more demineralization; and Propolis did not differ from NC. CONCLUSION Green tea, Black tea, Grape seed extract and Grapefruit seed extract were able to modify the salivary pellicle and improve its protective effect against enamel erosion, but Rosehip tea and Cranberry extract caused erosion. CLINICAL RELEVANCE Some some bio-products, such as teas and natural extracts, improve the protective effect of the salivary pellicle against enamel erosion. More studies should be performed in order to test the viability of their use as active ingredients for oral care products

The effect of red wine in modifying the salivary pellicle and modulating dental erosion kinetics.

This study investigated the potential of red wine in modulating dental erosion kinetics in the presence or absence of salivary pellicle. Polished human enamel specimens were used in two conditions; presence or absence of acquired enamel pellicle; and subdivided according to exposure: red wine, orange juice, apple juice, or citric acid. The specimens were incubated in clarified whole human saliva (presence of acquired enamel pellicle) or in a humid chamber (absence of acquired enamel pellicle) for 2 h at 37°C, then in the test substances for 1 min, at 25°C, under shaking. This was repeated four times. Surface hardness was measured initially and after each cycle and surface reflection intensity was measured initially and after all cycles. In the presence of acquired enamel pellicle, red wine caused the least surface hardness loss, followed by orange juice, apple juice, and citric acid. Statistically significantly less surface reflection intensity loss was observed for red wine and orange juice than for apple juice and citric acid. In the absence of acquired enamel pellicle, red wine and orange juice caused less surface hardness loss than apple juice and citric acid. Orange juice showed the least surface reflection intensity loss, followed by red wine, citric acid, and apple juice. The polyphenol composition of these drinks can notably modulate the erosion kinetics

Plant extracts have dual mechanism on the protection against dentine erosion: action on the dentine substrate and modification of the salivary pellicle

Abstract To investigate the effect of some polyphenol-rich plant extracts on the protection of dentine against demineralization, both acting on the dentine and on the salivary pellicle. Dentine specimens (n = 180) were randomly distributed into 6 experimental groups (n = 30/group): Control (deionized water), Açaí extract, Blueberry extract, Green tea extract, Grape seed extract, and Sn2+/F− (mouthrinse containing stannous and fluoride). Each group was further divided into two subgroups (n = 15), according to the site of action of the substance: on the dentine surface (D) or on the salivary pellicle (P). The specimens were submitted to 10 cycles: 30 min incubation in human saliva (P) or only in humid chamber (D), 2 min immersion in experimental substances, 60 min of incubation in saliva (P) or not (D), and 1 min erosive challenge. Dentine surface loss (DSL), amount of degraded collagen (dColl) and total calcium release were analyzed. Green tea, Grape seed and Sn2+/F− showed significant protection, with least DSL and dColl. The Sn2+/F− showed better protection on D than on P, whereas Green tea and Grape seed showed a dual mode of action, with good results on D, and even better on P. Sn2+/F− showed the lowest values of calcium release, not differing only from Grape seed. Sn2+/F− is more effective when acting directly on the dentine surface, while Green tea and Grape seed have a dual mode of action: with a positive effect on the dentine surface itself, but an improved efficacy in the presence of the salivary pellicle. We further elucidate the mechanism of action of different active ingredients on dentine erosion, where Sn2+/F− acts better on the dentine surface, but plant extracts have a dual mode of action, acting on the dentine itself as well as on the salivary pellicle, improving the protection against acid demineralization