Search Results (6)

This article reviews the topic of stannous fluoride as an anti-caries additive in toothpastes. It is based on a literature survey carried out using Science Direct, supplemented by information from PubMed. The keywords used were stannous fluoride, toothpaste, clinical effects, caries, hypersensitivity, gingival health, structure and aqueous solutions. The initial searches covered the period 2015–2024 and identified 57 references. Older references cited in these papers, and also papers already known to the author, were also included. The information thus obtained shows that stannous fluoride has three main effects, namely, reduction in the viability of the oral biofilm, increase in remineralisation of the hydroxyapatite tooth mineral and occlusion of dentinal tubules leading to reduced hypersensitivity. Stannous fluoride was shown to be the most effective of all the fluoride additives used in toothpastes. In much of the dental literature, this is attributed to the effects of Sn²⁺ ions. However, as has been shown extensively in the wider scientific literature, free Sn²⁺ ions do not occur in aqueous systems. Rather, the initial products of the dissolution of SnF₂ is undissociated, hydrated SnF₂ and SnF⁺ ions. These gradually exchange fluoride to form Sn(OH)₂ and Sn(OH)⁺. Their likely mechanism of action based on their toxicity towards oral micro-organisms and their interaction with hydroxyapatite is discussed. Full article

Purpose: This study evaluates the effects of different toothpastes on the nanohardness and chemical compositions of restorative materials and dental surfaces. Methods: Bovine enamel (n = 72) and dentin (n = 72) blocks were obtained and restored using RMGIC (n = 36) or CR (n = 36) to create the following surfaces: dentin adjacent to RMGIC (DRMGIC), enamel adjacent to RMGIC (ERMGIC), dentin adjacent to CR (DCR), and enamel adjacent to CR (ECR). After restoration, one hemiface of each specimen was coated with an acid-resistant varnish to facilitate the creation of control (C) and eroded (E) sides; the latter were achieved by erosion–abrasion cycles as follows: erosion with 1% citric acid: 5 days, four times for 2 min each day; 1% citric acid/abrasion, two times for 15 s, followed by immersion in a toothpaste slurry for 2 min. Toothpastes without fluoride (WF; n = 12), with sodium fluoride (NaF; n = 12), and with stannous fluoride (SnF₂; n = 12) were used for RMGIC or CR. The specimens were analyzed for nanohardness (H), and chemical composition using energy-dispersive X-ray spectroscopy and Raman microscopy. The data were statistically analyzed using two-way repeated measures ANOVA and Tukey’s test (α = 0.05). Results: Lower H values were obtained with NaF for DRMGIC-C, with a statistically significant difference from the H value obtained with WF (p < 0.05). The calcium and phosphorus concentrations in DCR-E were significantly lower with WF than with the other types of toothpaste (p < 0.05). Fluoride-containing toothpastes are capable of preserving the main chemical components of the dentin adjacent to the restorative materials under erosive–abrasive conditions. Full article

The sol-gel process was used to create a new type of polypyrrole-Stannous(II)tungstate nanocomposite by poly(N-methyl pyrrole (PNMPy) sol in Stannous(II)tungstate gel, produced separately using sodium silicotungstic acid and Tn(II)chloride. Tin(II)tungstate (SnWO₃) was made by changing the mixing volume ratios of SnWO₃ and with a constant amount of an organic polymer. The composite was characterized by TGA, XRD, FTIR, and SEM measurements. A commercially available glassy carbon electrode (GCE) was modified with PNMPy/nano-Stannous(II)WO₃ nanocomposites to create a chemical sensor for selective detection of Hg²⁺ ions using an effective electrochemical methodology. In the I-V technique, selectively toxic Hg²⁺ ion was targeted selectively, which shows a rapid reaction toward PNMPy/nano-Stannous(II)WO₃/Nafion/GCE sensor. It also demonstrates long-term stability, an ultra-low detection limit, exceptional sensitivity, and excellent reproducibility and repeatability. For 0.1 mM to 1.0 nM aqueous Hg²⁺ ion solution, a linear calibration plot (r²: 0.9993) was achieved, with a suitable sensitivity value of 2.8241 AM⁻¹ cm⁻² and an extraordinarily low detection limit (LOD) of 3.40.1 pM (S/N = 3). As a result, the cationic sensor modified by PNMPy/nano-Stannous(II)WO₃/GCE could be a promising electrode. Full article

These structurally isomeric rhodamine 6G-based amino derivatives are designed to detect Sn²⁺ ions. The receptors exhibit rapid fluorescent “turn-on” responses towards Sn²⁺. The absorption (530 nm) and fluorescent intensity (551 nm) of the receptors increase when increasing the concentration of Sn²⁺. The hydrazine derivative exhibits more rapid sensitivity towards Sn²⁺ than the ethylene diamine derivative, indicating that the presence of an alkyl chain in the diamine decreases the sensitivity of the receptors towards Sn²⁺. The presence of carbonyl groups and terminal amino groups strongly influences the sensitivity of the chemosensors toward Sn²⁺ by a spirolactam ring-opening mechanism. The receptors exhibit 1:1 complexation with Sn²⁺ as evidenced by Job plot, and the corresponding limit of detection was found to be 1.62 × 10⁻⁷ M. The fluorescence images of the receptors and their complexes reveal their potential applications for imaging of Sn²⁺ in real/online samples. Full article

The aim of this randomized, controlled clinical trial was to isolate and identify viable microorganisms in the saliva of study participants that continuously used a stannous and fluoride ion (F/Sn)-containing toothpaste and mouth rinse over a period of three years in comparison to a control group that used stannous ion free preparations (noF/Sn) over the same time period. Each group (F/Sn and noF/Sn) included 16 participants that used the respective oral hygiene products over a 36-month period. Stimulated saliva samples were collected at baseline (T0) and after 36 months (T1) from all participants for microbiological examination. The microbial composition of the samples was analyzed using culture technique, matrix-assisted laser desorption ionization–time of flight (MALDI–TOF) mass spectrometry, and 16S rDNA Polymerase Chain Reaction (PCR). There were only minor differences between both groups when comparing the absolute values of viable microbiota and bacterial composition. The treatment with F/Sn led to a slight decrease in disease-associated and a slight increase in health-associated bacteria. It was shown that the use of stannous ions had no negative effects on physiological oral microbiota even after prolonged use. In fact, a stabilizing effect of the oral hygiene products containing stannous ions on the health-associated oral microbiota could be expected. Full article

The aim of this in vitro study was to evaluate the effects of a single dose application of two daily toothpastes on enamel exposed to acid attack. The research was conducted on human molars enamel fragments (n = 72). The two different toothpastes active ingredients were sodium fluoride (NaF) and stannous fluoride (SnF₂). They were compared in protecting the surface of the enamel exposed to three acids: citric acid, lactic acid and hydrochloric acid. A spectrophotometer was used to measure the calcium ions and phosphate released in the solutions by the enamel specimens. Afterward, ionic concentrations were analyzed through the t-Student test, in order to estimate the significance level (p < 0.05) of the solubility differences obtained between the treatment and control groups. Finally, sample surfaces were analyzed with scanning electron microscopy and X-ray energy dispersive spectroscopy (SEM/EDX). The two analyzed toothpastes did not reveal any statistically significant variation in the release of calcium and phosphate (p > 0.05). Nevertheless, acid-resistant deposits were detected in samples treated with stannous fluoride and exposed to lactic acid, though the presence of tin ion deposits on samples treated with stannous fluoride was not shown. A single dose of a fluoride-based toothpaste before different acids attack, in simulated oral cavity conditions, did not show a significant preventive effect. Full article