Efficacy of a stannous fluoride dentifrice for relieving dentinal hypersensitivity in Chinese population: an 8-week randomized clinical trial.

OBJECTIVES: To compare the effectiveness of using a 0.454% stannous fluoride-containing dentifrice twice daily in relieving dentinal hypersensitivity (DH) in a Chinese population. MATERIALS AND METHODS: This was a single-centre, randomized, controlled, examiner-blind, three-treatment-arm, parallel-group study in participants with clinically diagnosed DH. Subjects who met inclusion criteria (n = 197) were randomly allocated into 3 groups: test group (n = 66)-using a 0.454% stannous fluoride-containing dentifrice twice daily; positive control group (n = 64)-using a 5.0% calcium sodium phosphosilicate-containing dentifrice twice daily; negative control group (n = 67)-using a 1150 ppm of NaF dentifrice twice daily. Status of DH was assessed at week 4 and week 8 by the same independent examiner. Changes from baseline in Schiff sensitivity score, tactile threshold and Dentine Hypersensitivity Experience Questionnaire (DHEQ) score were analysed using analysis of covariance models. The DHEQ evaluated subject-perceived oral health-related quality of life (OHRQoL). RESULTS: Statistically significant improvements in mean Schiff scores (p < 0.0001 for all products at Weeks 4 and 8), tactile threshold (p < 0.0001 for test and negative control at Weeks 4 and 8: Week 4 p = 0.0040 and Week 8 p < 0.0001 for positive control) and all DHEQ scores (p < 0.01 for all groups) were observed. No statistically significant differences were observed in the adjusted mean between all dentifrices at both timepoints, potentially driven by a placebo effect. Forty-two treatment-emergent adverse events (TEAEs) were reported (n = 32 subjects), with 2 serious AEs (n = 1) in the test group. TEAEs were not considered treatment-related. CONCLUSIONS: All groups demonstrated statistically significant improvements in Schiff score, tactile threshold and OHRQoL. However, due to a possible placebo effect in the negative control, there were no statistically significant differences between the dentifrices. CLINICAL RELEVANCE: This study adds to the growing research exploring why the placebo effect is a common phenomenon in DH studies. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT04950465.

Unexpected sequel to the application of silver fluoride followed by stannous fluoride to an open carious lesion in a primary molar: A case report.

OBJECTIVES: The use of silver fluoride followed by stannous fluoride was designed for the treatment of open carious lesions in primary molars in dental outreach programs. However, during the COVID-19 pandemic when aerosol-producing procedures were inadvisable, one dental location started using it as the first stage in a two-visit restorative procedure for carious primary molars. If the gap between the fluoride application and the restoration placement stages was around 3-5 weeks it was noticed that a black friable crust appeared on the caries surface. To investigate further a normally discarded crust from one patient was retrieved and sent for analysis. MATERIALS AND METHODS: Two techniques suitable for identification and preliminary analysis of material of unknown composition, scanning electron microscopy and energy dispersive spectroscopy (EDS) were used. The only preparation was that the specimen was dried and coated beforehand. RESULTS AND CONCLUSIONS: This preliminary examination showed two unexpected findings. The first was that the crust surface indicated a possible dentine derivation as it was covered with reasonably evenly spaced holes. In addition, the EDS spectrum showed it to be, at least, partially mineralized. The second unexpected finding was that the surface was coated with electron-dense particles. The size of the particles and the EDS spectrum pointed to the likelihood of the majority of them being nanosilver. These unexpected findings suggest a possible new direction for research.

Remineralisation of enamel and dentine with stabilised stannous fluoride dentifrices in a randomised cross-over in situ trial.

OBJECTIVES: To compare the remineralisation efficacy and ion bioavailability of two novel SnF2-containing dentifrices in a blinded, cross-over, randomised in situ clinical study. METHODS: Six participants wore removal palatal appliances holding human enamel and dentine blocks with subsurface lesions. Appliances were worn for two treatment periods of 14 consecutive days each, with a one-week washout period in-between. Participants were randomly allocated to rinse with a 1:5 diluted coded slurry of one of two dentifrices containing either 5 % casein phosphopeptide-amorphous calcium phosphate (CPP-ACP) +1100 ppm F as SnF2 [MIPOP], or 1100 ppm F as SnF2 [CT], for 1 min, four times a day. Saliva was collected post-treatment and analysed for tin, calcium, inorganic phosphate and fluoride ions using atomic absorption spectrophotometry and ion chromatography. Enamel and dentine lesions were analysed for percent remineralisation (%R) using transverse microradiography and percent surface microhardness recovery (%SMHR). RESULTS: MIPOP released significantly higher F (3.00 ± 0.27 mM), Ca (15.23 ± 3.23 mM) and Sn (1.18 ± 0.13 mM) into saliva whereas CT released 2.89 ± 0.32 mM F and only 0.84 ± 0.11 mM Ca and 0.28 ± 0.10 mM Sn. MIPOP produced significantly higher %R than CT: 25.6 ± 1.5 % compared to 15.2 ± 0.7 % in enamel, and 33.6 ± 3.1 % compared to 20.6 ± 1.1 % in dentine. Additionally, MIPOP produced significantly higher %SMHR (18.2 ± 7.9 %) compared to CT (4.1 ± 0.6 %). CONCLUSIONS: Both dentifrices promoted remineralisation, but the MIPOP dentifrice with added CPP-ACP and the ion-stabilising effects of CPP released higher amounts of bioavailable tin and produced significantly higher remineralisation and surface microhardness recovery. CLINICAL SIGNIFICANCE: Modern dentifrices contain SnF2 for a range of oral health benefits. Challenges associated with stability of these formulations can affect ion bioavailability, reducing efficacy. Two dentifrices with SnF2 promoted remineralisation in situ, however the dentifrice with the added saliva biomimetic CPP-ACP was superior and therefore may produce greater health benefits.

Characteristics of tin-containing fluoride toothpastes related to erosive tooth wear protection.

OBJECTIVES: To assess the effect of different tin-containing toothpastes on the control of erosive tooth wear in enamel and dentin. METHODS: Enamel and dentin slabs were randomly distributed into 7 experimental groups (n = 10/substrate): C-: negative control (Artificial saliva); AmF (regular fluoridated toothpaste without tin); Sn-1 (SnF2/NaF); Sn-2 (SnF2/NaF/SnCl2); Sn-3 (SnCl2/NaF); Sn-4 (SnF2/SnCl2); Sn-5 (SnCl2/AmF/NaF/chitosan). Specimens were submitted to 5-day erosion-abrasion cycling. Surface loss (SL) was determined with an optical profilometer. Tin deposition on the tooth surfaces and some characteristics of the toothpastes (pH, potentially available F-, %weight of solid particles, and RDA) were also assessed. Data were statistically analyzed (α = 0.05). RESULTS: For enamel, the Sn-2 presented the lowest SL, not differing significantly from AmF, C+, and Sn-3. The SL of these groups was significantly lower than the C-, except for Sn-3. Sn-1 and Sn-4 were also not significantly different from C-. For dentin, C- significantly showed the highest SL values, whilst, Sn-1 presented the lowest SL, not differing significantly from AmF, Sn-2, C+, and Sn-3. There was a significant positive association between enamel SL and the pH and tin deposition. Dentin SL was significantly negatively associated with the %weight of solid particles and RDA. CONCLUSIONS: Most of the tin-toothpastes were able to exhibit some protection against ETW. In this process, the toothpastes characteristics play a role, as lower enamel SL was significantly associated with lower pH values and tin deposition; and lower dentin SL was associated with higher %weight of solid particles and RDA of the toothpastes. CLINICAL SIGNIFICANCE: Tin-containing toothpastes can be used for erosive tooth wear protection, but our study showed that their effect depends on the pH, amount of tin deposition, % weight of solid particles and RDA of the toohpastes.

Fluoruro de estaño en el control de cavidades sin restauración en dientes temporales / Stannous fluoride in nonrestorative cavity control in primary teeth

Introducción: el control de cavidades sin restauración (NRCC, por sus siglas en inglés), es una opción de tratamiento conservador y no invasivo para dentina cariosa, sobre todo en dentición temporal. Una de las estrategias del NRCC es la remineralización. El fluoruro de estaño (FDE) puede considerarse, como una opción viable ya que existe evidencia de su eficacia cariostática. Objetivo: valorar al FDE como remineralizante alternativo en dentina de molares temporales, asociado al NRCC. Material y métodos: se efectuó un estudio clínico, epidemiológico, y descriptivo con preescolares voluntarios de 3 a 5 años de edad con consentimiento firmado de participación en el estudio, y que presentaron molares con ICDAS 5 y 6. La aplicación del FDE a 0.8%, la evaluación de la dureza de la dentina con los criterios de Nyvad, y el diagnóstico del estado pulpar, la efectuó un operador entrenado para esta finalidad. Se aplicó un análisis estadístico descriptivo y uno no paramétrico. Resultados: el efecto cariostático producido por el FDE a 0.8%, sobre dentina afectada de molares temporales de niños mexicanos fue estadísticamente significativo durante cinco meses. Conclusiones: la aplicación de fluoruro de estaño puede considerarse como una alternativa de tratamiento cariostático asociado al NRCC para niños de 3 a 5 años de edad (AU)

Introduction: nonrestorative cavity control (NRCC), is a conservative and non-invasive treatment option for carious dentin, especially in primary dentition. One of the NRCC strategies is remineralization. Stannous Fluoride (SDF) can be considered as a viable option since there is evidence of its cariostatic efficacy. Objective: to evaluate FDE as an alternative remineralizing agent in the dentin of primary molars, associated with NRCC. Material and methods: a clinical, epidemiological, and descriptive study was carried out with preschool volunteers aged 3 to 5 years with signed consent to participate in the study, and who presented molars with ICDAS 5 and 6. The application of FDE at 0.8%, the evaluation of dentin hardness with the Nyvad criteria, and the diagnosis of pulp status, was carried out by an operator trained for this purpose. A descriptive and non-parametric statistical analysis was applied. Results: the cariostatic effect produced by 0.8% FDE on affected dentin of primary molars of Mexican children was statistically significant for five months. Conclusions: the application of stannous fluoride can be considered as an alternative cariostatic treatment associated with NRCC for children 3 to 5 years of age (AU)

High-Resolution Characterization of Enamel Remineralization Using Time-of-Flight Secondary Ion Mass Spectrometry and Electron Microscopy.

INTRODUCTION: The aim of this in vitro study was to assess the suitability of high-resolution time-of-flight secondary ion mass spectrometry (ToF-SIMS) for visualizing cross-sectional changes in human enamel microstructure and chemical composition during treatment and remineralization cycling of artificially generated caries lesions underneath an artificial plaque. METHODS: Treatments consisted of exposure to twice daily toothpaste/water slurries prepared from 0, 1,100, and 5,000 µg/g fluoride (F) NaF/silica toothpastes. In addition, treatments with slurries prepared from 1,100 µg/g F SnF2/silica toothpastes were done using 44Ca in the remineralization solution to allow for differentiation of newly formed mineral and exploration of incorporated metal dopants using ToF-SIMS. Complementary microhardness, scanning electron microscopy, and high-resolution transmission electron microscopy (HR-TEM) investigations were performed on enamel cross sections. RESULTS: HR-TEM was used for the first time to determine the change in crystallinity during remineralization revealing distinct microstructural zones within one lesion. Chemical mapping using ToF-SIMS demonstrated that the distribution of F, while observed primarily in the new mineral phase, was widespread throughout the lesion with 44Ca substantially limited to the remineralizing mineral. Both penetrated the inter-rod spaces of the sound enamel illustrating how acid damage propagates into the native mineral as the caries lesion deepens. HR-TEM examination revealed different regions within the lesion characterized by distinct micro- and ultrastructures. Importantly, HR-TEM revealed a return of crystallinity following remineralization. F dose-response observations verified the ability of these high-resolution techniques to differentiate remineralization efficacy. CONCLUSION: The collective results provided new insights such as the visualization of F or calcium penetration pathways, as well as new tools to study the caries process.

Avaliação de um gel contendo fluoreto e estanho como uma opção de tratamento profissional para o controle da erosão do esmalte e da dentina / Evaluation of a gel containing fluoride and stannous as an option for the professional treatment of enamel and dentin erosion

Este estudo teve o objetivo de desenvolver um gel experimental contendo flúor e estanho, como uma opção de tratamento profissional, para ser utilizado na prevenção da erosão dental. Foram utilizados 50 fragmentos (4mm × 4mm × 2mm) de esmalte e 50 de dentina, obtidos de incisivos bovinos. Os fragmentos foram incluídos em resina acrílica, planificados e polidos. Em seguida, uma fita adesiva foi posicionada sobre a superfície polida desses espécimes, deixando uma janela de 4mm × 1mm exposta aos testes subsequentes. Os espécimes foram previamente erodidos (10min em solução de ácido cítrico a 1%, pH~2,4) e distribuídos aleatoriamente em cinco grupos experimentais (n=10 para cada substrato), de acordo com os seguintes tratamentos: 1. F+Sn+HPMC: Gel de fluoreto de sódio e cloreto de estanho experimental (7500 ppm F- e 15000 ppm Sn2+, pH=4,5); 2. F+HPMC: Gel de fluoreto de sódio experimental (7500 ppm F-, pH=4,5); 3. Comercial: Gel de flúor fosfato acidulado comercial - APF (12300 ppm F-, pH=3,2); 4. Placebo: Gel placebo (Hidroxipropil MetilceluloseHPMC, sem componentes ativos); 5. Controle negativo: sem tratamento; aplicados por 60 s. Na sequência, os espécimes foram submetidos a uma ciclagem de erosão-re-deposição mineral, que consistia em 5 min de imersão em solução de ácido cítrico a 0,3% (pH~2,6), seguido de imersão em saliva artificial por 60min, 4x/dia, durante 5 dias. A perda de superfície dos espécimes (PS em m) foi determinada com um perfilômetro óptico após 5, 10 e 20 dias de ciclagem. Os dados obtidos foram analisados com ANOVA de dois fatores de medidas repetidas, considerando um nível de significância de 5%. Para o esmalte, o placebo não diferiu do controle em nenhum tempo experimental, e ambos apresentaram significativamente a maior PS. Após 5 e 10 dias: (F+Sn+HPMC)=(comercial)<(F+HPMC)<(placebo)=(controle). Após 20 dias: (F+Sn+HPMC)=(F+HPMC)=(comercial)<(controle)=(placebo). Para dentina, no 5º dia: (comercial)=(F+Sn+HPMC)=(F+HPMC)<(controle)=(placebo). No 10º dia, os grupos F+Sn+HMC, comercial e F+HPMC continuaram apresentando menor PS do que o controle e o placebo, porém, F+HPMC não diferiu significativamente desses dois últimos grupos. No 20º dia, somente o comercial apresentou menor PS que controle e placebo. Considerando as limitações desse estudo in vitro, pode-se concluir que o gel de F+Sn+HPMC foi capaz de controlar a progressão da erosão dental de maneira semelhante ao gel comercial, que possui 4800 ppm a mais de fluoreto em sua composição, exceto após 20 dias de desafio erosivo na dentina. Esse gel é uma alternativa clínica viável, podendo ser potencialmente utilizado em conjunto com produtos de uso diário, visando o aumento da proteção contra erosão em indivíduos com alto risco para erosão dental.

Effect of Polyphenols on the Ultrastructure of the Dentin Pellicle and Subsequent Erosion.

INTRODUCTION: Erosive tooth wear is a highly prevalent dental condition that is modified by the ever-present salivary pellicle. The aim of the present in situ study was to investigate the effect of polyphenols on the ultrastructure of the pellicle formed on dentin in situ and a subsequent erosive challenge. METHODS: The pellicle was formed on bovine dentin specimens for 3 min or 2 h in 3 subjects. After subjects rinsed with sterile water (negative control), 1% tannic acid, 1% hop extract, or tin/fluoride solution containing 800 ppm tin and 500 ppm fluoride (positive control), specimens were removed from the oral cavity. The erosive challenge was performed on half of the specimens with 1% citric acid, and all specimens were analyzed by transmission electron microscopy. Incorporation of tannic acid in the pellicle was investigated by fluorescence spectroscopy. RESULTS: Compared to the negative control, ultrastructural analyses reveal a thicker and electron-denser pellicle after application of polyphenols, in which, according to spectroscopy, tannic acid is also incorporated. Application of citric acid resulted in demineralization of dentin, but to a lesser degree when the pellicle was pretreated with a tin/fluoride solution. The pellicle was more acid-resistant than the negative control when modified with polyphenols or tin/fluoride solution. CONCLUSION: Polyphenols can have a substantial impact on the ultrastructure and acid resistance of the dentin pellicle, while the tin/fluoride solution showed explicit protection against erosive demineralization.

How do new runners maintain their running, and what leads to others stopping? A qualitative, longitudinal study.

Many people who start running do not maintain their behaviour change. We used qualitative, longitudinal methods to explore and interpret the experiences of new runners and answer the question, "What experiences explain how new runners maintain their running or explain why they stop?" We interviewed 20 new runners (all White British, 14 women, 6 men) about their experiences; we interviewed 10 until they stopped running and 10 until they maintained running for 6-12 months (65 interviews in total). We also conducted nine participant observations at a running club, invited external reflections at a running club, and analysed six sets of participant diaries. Four themes were constructed using a reflexive thematic analysis: (1) Identifying a meaningful "why"; (2) "Life gets in the way" of running; (3) Learning that I can run; and (4) Opportunities are unequal and experiences contrast. The runners' reasons for running helped us to interpret changes in their experiences through time. Meaningful reasons helped runners to learn that they can run, prioritise running, and prevent life getting in the way. These reasons tended to be reasons to run, as opposed to reasons to be physically active, and they related to their identity, values, special memories, relationships, enjoyment of running, or a personal goal. Nevertheless, social inequalities like gendered experiences, wealth, and health differences meant that opportunities and experiences of running differed, creating more barriers for some runners. When runners faced substantial barriers, having a meaningful reason was helpful but it was sometimes insufficient for maintenance. The analysis illustrates how people's reasons for exercise influence their experiences through time, the dynamic nature of people's exercise barriers and facilitators, and the unequal nature of opportunities and experiences.

Influence of Different Mouthwashes on the Efficacy of Fluoridated Dentifrices in Prevention of Enamel Erosion: An In Vitro Study.

AIM: The purpose of the current study was to evaluate the impact of three various mouthwashes on the effectiveness of fluoride dentifrices in preventing enamel erosion. MATERIALS AND METHODS: A total of 120 sound intact human premolar teeth which were extracted for orthodontic treatment were selected for the study. A 3 × 3 mm window section was positioned in the middle of the coronal surface of the tooth in order to define the study area. Each sample was placed in a solution of 1% citric acid (pH 3.5) for 10 minutes in order to produce an eroded surface. All samples were divided into two main groups (60 samples each) as follows: Group A for sodium fluoride dentifrices and group B for stannous fluoride dentifrices, again it is subdivided into: CHX: Chlohex ADS®, EO: Listerine®, CPC: Colgate® Plax (20 samples in each subgroup). After that, samples underwent the pH cycling model for 5 days. Samples were examined for surface loss using a scanning electron microscope. RESULTS: In sodium fluoride dentifrices group, before intervention, the surface loss was 3.12 ± 1.03 in CHX group, 3.08 ± 1.20 in EO group, and 3.09 ± 0.96 in CPC group. After intervention, the less surface loss found with CHX group (2.18 ± 0.84), followed by CPC (2.34 ± 0.74) and EO group (2.46 ± 0.97). In stannous fluoride dentifrices group, before intervention, the surface loss in CHX group was 3.26 ± 1.19, in EO group, it was 3.18 ± 1.31, and in CPC group, it was 3.22 ± 1.06. After intervention, the less surface loss found with CHX: group (1.90 ± 0.54), followed by CPC (2.24 ± 0.28) and EO group (2.38 ± 0.20). CONCLUSION: The present study concluded that the fluoride dentifrices' preventive effects against tooth surface loss were unaffected by a different mouthwashes with varying compositions and major constituents. In terms of erosion, fluoridated toothpaste containing stannous fluoride was found to provide better surface loss protection than sodium fluoride. CLINICAL SIGNIFICANCE: Primary prevention and the eradication of contributing causes are the greatest strategies for preventing erosion. Simultaneously, antibacterial agent in the mouthwashes may help in enhancing the effect of fluoride in the enamel, owing to their high affinity for teeth structures. Therefore, in addition to cause-related treatment, further efforts to reduce tooth tissue loss are also necessary.

The potential of galactomannan from Caesalpinia ferrea on erosive dentin wear reduction in vitro.

Gels containing juca seed galactomannan (JSG) were evaluated for their potential to prevent the progression of dentin erosive wear in an in vitro study with four experimental groups (n = 9). The treatments included distilled water (DW), 0.05% stannous fluoride (121 ppm F), and 0.5% or 1% JSG. The specimens underwent a cycle (3 times/day) consisting of immersion in 1% citric acid (5 minutes), treatment (5 minutes), and artificial saliva exposure (2 hours/overnight) for 5 days. Surface changes were assessed using mechanical profilometry (wear), scanning electron microscopy (SEM), and energy-dispersive X-ray spectroscopy (EDS). The data were analyzed using ANOVA followed by Tukey's post-test (p < 0.05). The negative control group exhibited the highest wear (6.0 µm ± 3.5), significantly differing from the group treated with 0.05% stannous fluoride gel (p = 0.007), which showed less dentin loss. The groups treated with 0.5% and 1% JSG showed results similar to the negative control (p = 0.661; p = 0.212, respectively) and the stannous fluoride group (p = 0.103; p = 0.379, respectively). In the SEM images, the specimen treated with stannous fluoride showed obliterated tubules, while the JSG gels formed crystals on the dentin surface, as confirmed by the presence of oxygen and calcium in the EDS analysis. Although the JSG gels showed similar results to the stannous fluoride, did not exhibit superior efficacy at the tested concentrations.

Film-Forming Polymers for Inhibition of Hydroxyapatite Dissolution: A Screening Study.

The aim of this study was to evaluate the effect of film-forming polymer solutions of different concentrations and pH values, either associated or not with sodium fluoride (F; 225 ppm F-), when applied during the initial stage of salivary pellicle formation, to prevent the dissolution of hydroxyapatite (HA), which was determined by the pH-stat method. Polyacrylic acid (PA), chitosan, sodium linear polyphosphate (LPP), polyvinyl methyl ether/maleic anhydride (PVM/MA), and propylene glycol alginate (PGA) were tested in three concentrations (lower, medium, and higher), two pH values (native or adjusted), and either associated or not with F. Distilled water, F, and stannous ion+fluoride (Sn/F; 225 ppm F- and 800 ppm Sn2+, as SnCl2) solutions were the controls, totalizing 63 groups. HA crystals were pretreated with human saliva for 1 min to allow pellicle formation, then immersed in the experimental solutions (1 min), and exposed to saliva for another 28 min. Subsequently, they were added to a 0.3% citric acid solution (pH = 3.8), connected to a pH-stat system that added aliquots of 28 µL 0.1 N HCl for a total reaction time of 5 min. Data were analyzed with one-way ANOVA and Tukey's tests (α = 0.05). For PA alone, the concentrations of 0.1% (native pH), 0.06%, and 0.08% (both pH adjusted) showed significantly lower HA dissolution than the negative control. PA concentrations of 0.1% and 0.08%, of both pH values, improved the effect of F against HA dissolution to a near-identical value as Sn/F. All solutions containing chitosan and LPP significantly reduced HA dissolution in comparison with the control. For chitosan, the concentration of 0.5% (in both pH values) improved the effect of F. LPP at 0.5% (native pH) and all associations of LPP with F outperformed the effect of F. Some PVM/MA solutions significantly reduced HA dissolution but PVM/MA could not improve the protection of F. PGA was incapable of reducing HA dissolution or improving F effect. It was concluded that chitosan, LPP, and some PA and PVM/MA solutions used alone were capable of reducing HA dissolution. Only PA, chitosan, and LPP were able to enhance fluoride protection, but for PA and chitosan, this was influenced by the polymer concentration.

Iron oxide nanozymes stabilize stannous fluoride for targeted biofilm killing and synergistic oral disease prevention.

Dental caries is the most common human disease caused by oral biofilms despite the widespread use of fluoride as the primary anticaries agent. Recently, an FDA-approved iron oxide nanoparticle (ferumoxytol, Fer) has shown to kill and degrade caries-causing biofilms through catalytic activation of hydrogen peroxide. However, Fer cannot interfere with enamel acid demineralization. Here, we show notable synergy when Fer is combined with stannous fluoride (SnF2), markedly inhibiting both biofilm accumulation and enamel damage more effectively than either alone. Unexpectedly, we discover that the stability of SnF2 is enhanced when mixed with Fer in aqueous solutions while increasing catalytic activity of Fer without any additives. Notably, Fer in combination with SnF2 is exceptionally effective in controlling dental caries in vivo, even at four times lower concentrations, without adverse effects on host tissues or oral microbiome. Our results reveal a potent therapeutic synergism using approved agents while providing facile SnF2 stabilization, to prevent a widespread oral disease with reduced fluoride exposure.

A randomized controlled clinical evaluation of desensitization efficacy of a newly developed toothpaste with highly stabilized SnF2.

PURPOSE: To assess the relief of dentin hypersensitivity of the new toothpaste with stabilized stannous fluoride (SnF2) versus a marketed standard fluoride toothpaste as a negative control and a marketed anhydrous SnF2 toothpaste as a positive control. METHODS: This was a single-centered, randomized, controlled, double blind, clinical trial. 96 participants with hypersensitivity were enrolled in this 4-week clinical study. Electrical stimulation and evaporative air tests were performed to evaluate the desensitization efficacy. Clinical assessments were made at baseline, and after 3 days, 1 week, 2 weeks and 4 weeks of twice-daily brushing. Additionally, the influence of Sn² ⁺ species on desensitization was evaluated using bovine dentin specimens treated with toothpaste. RESULTS: All 96 enrolled participants were randomized. 96 participants completed all evaluations. Participants had an average age (SD) of 47.0 (10.5) years; 45% of participants were female. Both SnF2 toothpastes showed superior desensitization efficacy compared to the negative control toothpaste, the conventional sodium monofluorophosphate (SMFP) toothpaste, after a week. The new stabilized SnF2 toothpaste demonstrated improved electrical stimulation benefits compared to the negative control toothpaste, with increases of 15.1% after 3 days, 34.2% after 1 week, 66.3% after 2 weeks, and 111.6% after 4 weeks. Additionally, it showed relative verbal evaluation scale (VES) benefits of 14.2% after 3 days, 37.6% after 1 week, 28.9% after 2 weeks, and 37.4% after 4 weeks. The stabilized SnF2 toothpaste exhibited desensitization properties comparable to those of a commercial anhydrous SnF2 toothpaste, which typically produces undesirable side effects in the mouth. Toothpastes containing 0.454 % SnF2 exhibited perfect occlusion of dentin tubules. CLINICAL SIGNIFICANCE: The stabilized 0.454% SnF2 toothpaste exhibited significantly greater dentin hypersensitivity relief within only a week and comparable property to commercial anhydrous SnF2 toothpaste.

Combined use of stannous fluoride-containing mouth rinse and toothpaste prevents enamel erosion in vitro.

OBJECTIVE: To compare the protective effect of commercial stannous-containing mouth rinses on enamel erosion in a simulated 5-day in vitro cycling model. MATERIALS AND METHODS: 81 human enamel specimens were embedded in resin blocks and divided into nine groups as follows; group 1: stannous fluoride (1000SnF2) toothpaste; groups 2,3, and 4 were the same as group 1 plus Elmex®, PerioMed™, and Meridol®, respectively, group 5: stannous fluoride (1450SnF2) toothpaste, groups 6, 7, and 8 were the same as group 5 plus Elmex®, PerioMed™, and Meridol®, respectively, group 9: negative control. An erosive challenge was induced with a 1 min hydrochloric acid (0.01 M, pH 2.2) treatment 3 times per day. Each cycle included immersing in the toothpaste slurry twice for two minutes and a one-minute rinse. The enamel slabs were immersed in artificial saliva between each erosive cycle and incubated overnight at 37 °C. Surface hardness loss and enamel loss were determined by Knoop surface hardness and non-contact profilometry, respectively. Finally, enamel surfaces were analyzed by scanning electron microscopy and X-ray energy dispersive spectroscopy (SEM/EDS). RESULTS: All three mouth rinses had similar protective effects against erosion when using adjunct with 1000 SnF2 toothpaste (p > 0.05). With 1450 SnF2 toothpaste, Elmex® presented significantly lower surface hardness loss than Meridol® (p < 0.05). The combined use of Elmex® or PerioMed™ with toothpaste provided significantly better erosion protection than toothpaste alone, either 1000 or 1450 SnF2. In addition, 1000SnF2 toothpaste adjunct with mouth rinse is comparable to 1450 SnF2 toothpaste alone in preventing enamel erosion. CONCLUSION: All three mouth rinses reduced enamel erosion. The additional use of a high concentration stannous containing mouth rinse with 1450 SnF2 toothpaste increases the protective effect against enamel erosion in vitro. CLINICAL SIGNIFICANCE: To date, no standard protocol for preventing dental erosion is available. There are three stannous-containing mouth rinses on the market; however, no study compared their efficacy or indicated whether using adjuncts with anti-erosion toothpaste provides additional benefits. This study found that adding stannous mouth rinse to twice-daily toothpaste increases erosion protection.

Erosion-inhibiting potential of the stannous fluoride-enriched CPP-ACP complex in vitro.

Currently available anti-erosive agents only provide partial protection, emphasizing the need to enhance their performance. By characterizing erosive enamel wear at the nanoscale, the aim of this in vitro study was to assess the anti-erosive effects of SnF2 and CPP-ACP both individually and synergistically. Erosion depths were assessed longitudinally on 40 polished human enamel specimens after 1, 5, and 10 erosion cycles. Each cycle comprised one-min erosion in citric acid (pH 3.0) and one-min treatment in whole saliva (control group) or a slurry of one of the three anti-erosive pastes (10% CPP-ACP; 0.45% SnF2 (1100 ppm F); or SnF2/CPP-ACP (10% CPP-ACP + 0.45% SnF2)) (n = 10 per group). Scratch depths were assessed longitudinally in separate experiments using a similar protocol after 1, 5, and 10 cycles. Compared with the control groups, all slurries reduced erosion depths after 1 cycle (p ≤ 0.004) and scratch depths after 5 cycles (p ≤ 0.012). The order of anti-erosive potential was SnF2/CPP-ACP > SnF2 > CPP-ACP > control for erosion depth analysis, and SnF2/CPP-ACP > (SnF2 = CPP-ACP) > control for scratch depth analysis. These data provide 'proof of concept' evidence that SnF2/CPP-ACP has superior anti-erosive potential compared to SnF2 or CPP-ACP alone.

Enamel Fluoride Uptake Determined Using the Microbiopsy Technique and Time-of-Flight Secondary Ion Mass Spectrometry: A Pilot Study.

This study evaluated the suitability of time-of-flight secondary ion mass spectrometry (ToF-SIMS) to assess enamel fluoride uptake (EFU) in comparison with the microbiopsy technique. Enamel specimens were exposed to equimolar solutions of fluoride prepared from sodium fluoride (NaF), stannous fluoride (SnF2), or amine fluoride (AmF). EFU was quantified by both techniques on the same specimens. EFU was found to be highest for samples treated with AmF, followed by SnF2 and NaF. Both methods yielded clearly interpretable, highly correlating (r = 0.95) data. ToF-SIMS can be considered a promising alternative to the microbiopsy technique for near-surface EFU assessment.

Occlusion of dentinal tubules on periodontally involved teeth by dentifrice containing stannous fluoride and sodium fluoride.

PURPOSE: This study examined the occlusion effect of a dentifrice containing stannous fluoride (SnF2) and sodium fluoride (NaF) on periodontally involved teeth in comparison with healthy teeth using scanning electron microscopy (SEM) in comparison with a dentifrice containing NaF alone. METHODS: Sixty dentine samples obtained from single-rooted premolars, 15 of them extracted for orthodontic reasons (Group H) and 15 because of periodontal destruction (Group P), were included in the study. Each group of specimens was further divided into subgroups: HC and PC (control), H1 and P1 (treated with SnF2 and NaF), and H2 and P2 (treated with NaF). The samples were brushed twice a day for 7 days, kept in artificial saliva, and examined by SEM. The diameters of open tubules and the numbers of tubules were assessed at ×2,000 magnification. RESULTS: The H and P groups showed similar diameters of open tubules. The numbers of open tubules in Groups H1, P1, H2, and P2 were significantly lower than in Groups HC and PC (P < 0.001), and consistent with the percentages of occluded tubules. Group P1 had the highest percentage of occluded tubules. CONCLUSIONS: Although both dentifrices were found to successfully occlude dentinal tubules, the dentifrice containing SnF2 and NaF provided the highest degree of occlusion in periodontally involved teeth.

A randomized double-blind clinical trial evaluating comparative plaque and gingival health associated with commercially available stannous fluoride-containing dentifrices as compared to a sodium fluoride control dentifrice.

BACKGROUND: Gingivitis is a non-specific inflammatory lesion in response to the accumulation of oral biofilm and is a necessary precursor to periodontitis. Enhanced oral hygiene practices, including utilization of a dentifrice that could significantly improve plaque accumulation and gingival inflammation, is desirable to prevent and treat gingivitis and potentially prevent progression to periodontitis. This clinical study aimed to investigate the effect of a new stannous fluoride-containing dentifrice with 2.6% ethylenediamine tetra acetic acid (EDTA) as an anti-tartar agent to reduce plaque index and gingival index over a 3-month study period compared to other commercially-available fluoride-containing dentifrices. METHODS: This double-blind, randomized controlled clinical study evaluated plaque, gingival inflammation, and sulcular bleeding in patients using one of five commercially available fluoride-containing dentifrices The dentifrices tested contained: 0.454% stannous fluoride and 2.6% EDTA (D1), 0.24% sodium fluoride (C), and 0.454% stannous fluoride (D2-D4). One hundred fifty subjects participated over a 3-month period. Co-primary endpoints were improvements in plaque index (PI) and modified gingival index (mGI) from baseline values. No professional cleaning was performed during the study period. RESULTS: All subjects in the study demonstrated statistically significant improvements in all measures of oral hygiene over the 3-month study period. Subjects using dentifrice 1 (D1) showed statistically significantly greater reductions in PI, mGI, and modified sulcular bleeding index (mSBI) compared with all other commercially-available dentifrices tested (p < 0.00001). CONCLUSIONS: A new dentifrice with 0.454% stannous fluoride and 2.6% EDTA demonstrated significant improvements in clinical parameters associated with gingivitis compared to other sodium and stannous fluoride containing dentifrices.