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.

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.

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.

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.

Virucidal Activity of Over-the-Counter Oral Care Products Against SARS-CoV-2

PURPOSE

The oral cavity is an important entry point for SARS-CoV-2 infection. This study tested whether four commercially available mouthrinses and dentifrices have in vitro virucidal activity against SARS-CoV-2 (=4 log10 reduction in viral titer).

MATERIALS AND METHODS

One part of stock SARS-CoV-2 virus plus one part 0.3 g/l bovine serum albumin were mixed with eight parts of test product solution. After 30 s for the rinses, or 60 s for the dentifrices, the mixture was quenched in an appropriate neutralizer, serially diluted, and inoculated onto Vero E6 cells to determine viral titer. Triplicate runs were performed for each test condition with appropriate controls for test product cytotoxicity, viral interference, and neutralizer effectiveness. Test products included: 1.5% hydrogen peroxide (H2O2) rinse; 0.07% cetylpyridinium chloride (CPC) rinse; 0.454% stannous fluoride (SnF2) dentifrice A; and 0.454% SnF2 dentifrice B.

RESULTS

?The 1.5% H2O2 rinse, 0.07% CPC rinse, SnF2 dentifrice A, and SnF2 dentifrice B all produced > 4 log10 reduction in SARS-CoV-2 titer.

CONCLUSION

All four test products displayed potent virucidal activity in vitro. Clinical studies are warranted to determine what role, if any, these oral care products might play in preventing transmission of SARS-CoV-2 or in the management of patients currently diagnosed with COVID-19 illness.

The relative clinical efficacy of three 0.454% stannous fluoride dentifrices for the treatment of gingivitis over 3 months

PURPOSE

To assess the safety and efficacy of three stannous fluoride (SnF2) dentifrices in the reduction of gingivitis versus a negative control dentifrice.

METHODS

This was a randomized, controlled, double-blind, four-treatment parallel group study. 120 healthy adult volunteers with established gingivitis were enrolled and randomly assigned to one of four dentifrice treatment groups (30/group): 0.454% SnF2 + citrate dentifrice A; 0.454% SnF2 + sodium hexametaphosphate dentifrice B; 0.454% SnF2 + pyrophosphate dentifrice C; or 0.76% sodium monofluorophosphate negative control group. Subjects brushed with their assigned dentifrice and an assigned regular manual toothbrush (Oral-B Indicator) for 1 minute twice daily for 12 weeks. Number of gingival bleeding sites and Löe-Silness Gingival Index (LSGI) scores were assessed at baseline and at Weeks 2, 4 and 12.

RESULTS

120 subjects were enrolled and 112 completed the trial. Subjects had an average age (SD) of 39.31 (14.5) years; 67% of subjects were female. Overall baseline means (SD) were 81.2 (25.6) for number of bleeding sites and 1.51 (0.197) for mean LSGI score. Baseline disease levels were balanced across all treatment groups. At Week 2, SnF2 dentifrices A and B demonstrated a significant reduction in gingival bleeding sites versus the negative control; however, SnF2 dentifrice C was not significantly different from the negative control (P= 0.15). At Weeks 4 and 12, all SnF2 dentifrices demonstrated a significant gingival bleeding site reduction versus the negative control (P< 0.001). At Weeks 2, 4 and 12, the SnF2 dentifrices were rank ordered dentifrice A > dentifrice B > dentifrice C for reduction in gingival bleeding sites (P< 0.001). The same trends were seen for LSGI scores.

CLINICAL SIGNIFICANCE

In this 12-week clinical study, all 0.454% SnF2 dentifrices delivered statistically significant reductions in the number of gingival bleeding sites relative to the negative control. Importantly, statistically significant efficacy differences were observed among the three 0.454% SnF2 dentifrices, demonstrating the important role that differences in formulation have on clinical efficacy.

Efficacy of a Stannous-containing Dentifrice for Protecting Against Combined Erosive and Abrasive Tooth Wear In Situ

PURPOSE

The in-situ efficacy of an experimental stannous (Sn)-containing sodium fluoride (NaF) dentifrice against erosion and erosive tooth wear was compared with a conventional NaF dentifrice.

MATERIALS AND METHODS

This was a randomised, controlled, double-blind, parallel-group clinical trial. Mandibular appliances containing four enamel specimens (2 per side [L/R] of the appliance) were worn by 60 generally healthy adult subjects. Subjects were randomised to treatment based on age and gender. Treatments included a Sn-containing NaF or conventional NaF dentifrice. Conditions of erosion (dentifrice slurry treatment) and erosion/tooth wear (dentifrice slurry plus brushing) were compared. Dentifrices were used twice per day for 30 s of lingual brushing, followed by 90 s of slurry exposure. In addition, the two specimens on the left side of the mouth were brushed for 5 s each, using a power toothbrush. All specimens were exposed to four daily erosive challenges with commercial orange juice (pH 3.6). Tooth wear was measured as enamel loss using non-contact profilometry on day 10.

RESULTS

At the day 10 visit, the adjusted mean (SE) enamel loss for specimens receiving slurry (erosion) treatment was 4.7 µm (0.61) [Sn-containing NaF] and 8.73 µm (1.12) [NaF control], with results demonstrating a statistically significant benefit for the Sn-containing dentifrice (46.2% benefit; p = 0.009). For specimens exposed to erosion/tooth wear conditions, enamel loss = 6.68 µm (1.29) (Sn-containing NaF) and 10.99 µm (1.29) (NaF group), with results statistically significant (p = 0.048; 39.2% better, favouring the Sn-containing dentifrice). When data were combined, enamel loss (SE) for all specimens subjected to erosion + erosion/tooth wear was 5.61 µm (0.77) (Sn-containing NaF]) and 9.9 µm (1.3) (NaF group). The difference again was statistically significant, favouring the Sn-containing group (p = 0.022; 43.4% better).

CONCLUSIONS

The Sn-containing dentifrice demonstrated significantly better protection than did NaF under erosive and erosive/tooth wear conditions.

Stabilized stannous fluoride dentifrice in relation to dental caries, dental erosion and dentin hypersensitivity: A systematic review

PURPOSE

To review the scientific evidence for the efficacy of stabilized stannous fluoride (SnF₂) dentifrice in relation to dental caries, dental erosion and dentin hypersensitivity.

METHODS

Medline OVID, Embase.com, and the Cochrane Library were searched until January 2018. Two researchers independently selected studies according to inclusion and exclusion criteria, data were extracted, the risk of bias in eligible studies was assessed and a meta-analysis was performed wherever feasible.

RESULTS

Three studies on dental caries, eight studies on dental erosion and 11 on dentin hypersensitivity were included. Risk of bias was judged as high for most of the caries and erosion studies and low or medium for the hypersensitivity studies. A similar or slightly higher anti-caries activity compared with non-stannous fluoride dentifrices was observed. Stannous fluoride showed a greater anti-erosive potential in seven of the eight studies. A mean difference score in favor of stannous fluoride dentifrices compared with controls was found in a meta-analysis including six 8-week hypersensitivity studies.

CLINICAL SIGNIFICANCE

The use of stabilized stannous fluoride dentifrices to relieve dentin hypersensitivity and to prevent the initiation of dental erosion speaks in favor of this treatment strategy.

Effect of stannous fluoride and zinc phosphate dentifrice on dental plaque and gingivitis: A randomized clinical trial with 6-month follow-up

OBJECTIVE

The objective of this study was to compare a stabilized stannous fluoride (SnF₂) dentifrice with zinc phosphate (Colgate Total^SF) with SnF₂ with zinc lactate and control fluoride dentifrices for gingivitis and plaque control over a 6-month period.

METHODS

A total of 135 adult participants were enrolled in this study. After randomization and blinding of examiners and patients, enrolled participants were provided instructions for use of assigned dentifrice. At 3 visits (0, 3, and 6 months), various gingival and plaque indexes were collected to determine the clinical efficacy of a stabilized SnF₂ dentifrice. These results were compared with a SnF₂ with zinc lactate dentifrice and with a control fluoride dentifrice.

RESULTS

A total of 135 participants completed the study. All groups reported statistically significant reductions in gingival inflammation and improvement in plaque control at 3- and 6-month follow-up. Both SnF₂ dentifrices showed statistically significant reductions in all indexes compared with the control dentifrice (P < .001). However, the test dentifrice showed higher but nonsignificant improvements in plaque and gingival indexes compared with the other SnF₂ dentifrice.

CONCLUSIONS

This study reports similar efficacy of a test dentifrice to a commercial SnF₂-containing dentifrice for plaque control and reduction in gingival inflammation and provides supporting evidence that the test dentifrice maintains its clinical efficacy with change of formulation.

PRACTICAL IMPLICATIONS

This newly formulated SnF₂ stabilized with zinc phosphate dentifrice may be of benefit to patients in controlling plaque biofilm and gingivitis.

Solving the problem with stannous fluoride: Extrinsic stain

BACKGROUND

This article highlights a stabilized stannous fluoride (SnF₂) dentifrice that, in addition to being efficacious against caries, gingivitis, and dentin hypersensitivity, demonstrates high-performing stain prevention and removal efficacy.

METHODS

An in vitro stain prevention model evaluated the efficacy of Colgate Total^SF containing 0.454% SnF₂ and 1% zinc phosphate compared with Crest Pro-Health Whitening Power (The Procter & Gamble Company) and a nonabrasive SnF₂ gel. L*, a*, and b* values were measured to assess whiteness comparing untreated and stained teeth, and with statistical analysis. A stain removal clinical study was conducted as a randomized, double-blind, 2-cell, parallel-group design using Colgate Total^SF and nonwhitening regular fluoride toothpaste. Participants were instructed to brush twice daily for 6 weeks and were examined for Lobene Composite Stain Index scores, with statistical analysis used at a significance of P < .001.

RESULTS

In an in vitro stain prevention study, Colgate Total^SF performed 26% and 35% better than a competitor paste and nonabrasive SnF₂ gel, respectively. In a clinical study, Colgate Total^SF use showed statistically significant extrinsic tooth stain reductions by 17.5% (3 weeks) and 27.8% (6 weeks) relative to regular fluoride toothpaste. No adverse effects were reported.

CONCLUSIONS

The results indicate that the stabilized Colgate Total^SF performed statistically better than other SnF₂ pastes in an in vitro study, and statistically better than a regular fluoride toothpaste in a clinical study.

PRACTICAL IMPLICATIONS

Colgate Total^SF offers an SnF₂-based therapeutic dentifrice with notable performance in stain prevention and removal.

Effect of a stannous fluoride toothpaste on dentinal hypersensitivity: In vitro and clinical evaluation

BACKGROUND

The authors conducted an in vitro and a clinical study to assess the effect of a toothpaste containing stannous fluoride to occlude dentin tubules and reduce dentinal hypersensitivity.

METHODS

For the in vitro study, the authors treated the surface of human dentin specimens with test or control toothpaste slurries and then evaluated them by using various spectroscopic techniques. For the clinical study, male and female participants who met the inclusion criteria brushed their teeth twice daily for 1 minute with test or control toothpaste. The authors assessed dentinal hypersensitivity by using tactile and air blast stimuli at baseline and after 4 and 8 weeks. All statistical tests of hypotheses were 2 sided, with a significance level of α set at .05.

RESULTS

Results from in vitro studies showed that the test toothpaste effectively occluded the dentinal tubules with a deposit consisting of tin, zinc, phosphate, and silicon. The test and control toothpastes occluded the tubules 82% and 35%, respectively. Clinically, at the 4- and 8-week examinations, the test toothpaste provided statistically significant (P < .001) improvements in tactile dentinal hypersensitivity scores of 27.8% and 42.0% and in air blast hypersensitivity scores of 21.4% and 32.3%, respectively, relative to the control toothpaste.

CONCLUSIONS

The in vitro results indicate the toothpaste containing 0.454% stannous fluoride effectively coated dentin surfaces and occluded patent dentin tubules. Compared with the control toothpaste, the test toothpaste provided a significant reduction in dentinal hypersensitivity after 8 weeks of product use.

PRACTICAL IMPLICATIONS

A multi-benefit option for patients with dentinal hypersensitivity.

The effects of bioavailable gluconate chelated stannous fluoride dentifrice on gingival bleeding: Meta-analysis of eighteen randomized controlled trials

AIM

To estimate gingivitis effects of a bioavailable gluconate chelated 0.454% stannous fluoride (SnF2 ) family of dentifrices in adult subjects versus positive (triclosan) and negative (NaF or MFP) controls when used ≤3 months.

MATERIALS AND METHODS

A meta-analysis evaluated bioavailable gluconate chelated SnF2 dentifrices versus a negative or positive control for gingival bleeding.

RESULTS

In 18 randomized controlled trials (RCTs) with 2,890 subjects assessing SnF2 paste versus a negative or positive control, the average number of bleeding sites was reduced by 51% and 31%, respectively. The average change (95% CI) in number of bleeding sites was -16.3 (-27.8, -4.9) versus the negative control and -3.6 (-5.4, -1.8) versus the positive control. Subjects with localized or generalized gingivitis had 3.7 times better odds (95% CI [2.8, 5.0]) of shifting to generally healthy using SnF2 versus a negative control and 2.8 times better odds (95% CI [2.1, 3.9]) of shifting to generally healthy using SnF2 versus a positive control. The individual study risk of bias was deemed to be low in all categories of bias.

CONCLUSION

This meta-analysis demonstrates significant gingivitis benefits of bioavailable SnF2 dentifrices when used ≤3 months versus positive (triclosan) and negative (NaF or MFP) controls.

Randomized in situ clinical trial evaluating erosion protection efficacy of a 0.454% stannous fluoride dentifrice

OBJECTIVES

To assess the protective effects of a 0.454% stabilized stannous fluoride dentifrice and a marketed triclosan dentifrice against enamel erosion in a 10-day in situ model.

METHODS

This was a double-blind, randomized, 2-treatment, 4-period, crossover in situ trial involving healthy adult participants. Participants were randomized to a treatment sequence involving the following products: a highly bioavailable 0.454% stannous fluoride dentifrice (Procter & Gamble) and a marketed dentifrice control containing 0.24% sodium fluoride and 0.3% triclosan (Colgate-Palmolive). Each study period took place over 10 days. Participants wore an intra-oral appliance retaining two polished human enamel samples for 6 hours per day. Two times per day they swished with the assigned dentifrice slurry and four times per day they swished with 250 mL of orange juice (25 mL per minute) over a 10-minute period. Contact profilometry measurements were made for each sample at baseline and day 10 to determine surface change.

RESULTS

Thirty-six participants were enrolled and 33 completed the study (mean age = 40.5 years). The stannous fluoride dentifrice demonstrated 93.5% less enamel loss than the NaF/triclosan dentifrice (P < 0.001) at Day 10, with median enamel loss of 0.097 µm and 1.495 µm, respectively. Both products were well tolerated.

CONCLUSION

The stannous fluoride dentifrice demonstrated significantly greater erosion protection efficacy relative to the NaF/triclosan dentifrice in this randomized in situ clinical trial.

[The increased sensitivity of dentin: the mechanisms of remineralization using toothpaste with tin fluoride]

The purpose of the study was clinical and laboratory analysis of the remineralizing properties and clinical efficacy of the course application of the Sensodyne Rapid Relief therapeutic and prophylactic toothpaste for sensitive teeth with tin fluoride. The study involved 50 overwise healthy patients aged from 18 to 25 years diagnosed with a localized form of hyperesthesia of hard dental tissues and no signs of acute inflammation of periodontal tissues. After 7 days of clinical observation and daily use of the toothpaste the hygienic condition of the oral cavity in all patients improved: oral hygiene index was 1.02±0.2 units; gum inflammation index (PMA) - 8.0±1.5%; the absence of hyperesthesia was diagnosed (1 point, p≤0.05). Examination of patients after 14 and 28 days confirmed the absence of pain in 100%, the organoleptic properties of the toothpaste under investigation were also highly appreciated by the participants. A laboratory study showed that patients have an increase in the pH value of mixed saliva and a decrease in its buffer capacity by 13.4±2.25%, which contributes to a more effective remineralizing effect of calcium ions by calcium-binding proteins of mixed saliva. The concentration of fluoride ions in the saliva of patients of both groups increased by average rate of 34±0.5% per week. The combination of tin and fluoride is more effective than fluoride alone. The presence of tin ions causes a higher ability of fluorides to bind with calcium ions on the surface of the dentin and dentinal tubules, inhibits the process of demineralization, enhances the additive interaction of the ions forming the acid-resistant layer on the surface of the dentin and dentinal tubules, leading to a decrease in hyperesthesia of the teeth.

Subgingival uptake and retention of stannous fluoride from dentifrice: Gingival crevicular fluid concentrations in sulci post-brushing

PURPOSE

To examine the delivery of stannous fluoride to subgingival sulci following toothpaste use in a clinical population.

METHODS

This was a controlled, single-site study. 23 subjects with at least 20 dental pockets, 2-4 mm with bleeding, who had not used a stannous fluoride dentifrice in the last 3 months were enrolled. After a 2-week washout period, 20 subjects returned for a baseline visit. They were instructed to refrain from brushing the night before the baseline visit. GCF samples were taken from up to 10 sites identified as sampling sites. Subjects were then given a 0.454% stannous fluoride dentifrice and soft manual toothbrush and asked to brush for 1 minute. 30 minutes after brushing, GCF was re-sampled. Subjects continued using the stannous fluoride dentifrice and soft manual toothbrush at home, twice daily for 2 weeks, in place of their usual hygiene products. At Days 1 and 14, subjects returned to the site, and 12 hours post-brushing GCF samples were taken. The samples were analyzed by ICP-MS (inductively coupled plasma mass spectrometry). A Wilcoxon signed-rank test was performed to determine the difference between post-baseline visits and baseline. Statistical tests were 2-sided using a 5% significance level.

RESULTS

20 subjects completed the trial. Significant levels of tin, a marker for stannous fluoride, were detected 30 minutes after brushing at sampling sites of 2-4 mm. The median tin level in gingival crevicular fluid (GCF) was 24.59 ng/µl, which was highly significant versus baseline (P< 0.0001). Tin levels sampled in GCF 12 hours after brushing on Days 1 and 14 were highly significant versus Baseline (P< 0.0001), showing an increasing trend with continued use.

CLINICAL SIGNIFICANCE

Stannous fluoride was found to penetrate sampling sites from 2-4 mm and was retained for 12 hours. Subgingival uptake and retention of stannous fluoride following toothbrushing may play a role in detoxification effects on microbial biofilms and may contribute to the therapeutic efficacy of stannous fluoride dentifrices in promoting gingival health.

Initial evidence of two-step dentifrice/gel sequence effects on health: Outcomes from three randomized controlled trials

PURPOSE

Health-related outcomes from three randomized controlled trials represented the initial research on the feasibility of novel, sequential oral hygiene with a stannous fluoride (SnF₂) dentifrice then hydrogen peroxide (H₂O₂) whitening gel.

METHODS

One crossover and two parallel clinical trials were conducted independently. Objectives varied, with individual studies assessing short, intermediate or longer-term outcomes from breath, dental plaque or gingivitis, respectively. Treatments were randomly assigned, and blinded test kits were dispensed containing either: 1) a two-step 0.454% SnF₂ dentifrice and then a 3% H₂O₂ whitening gel sequence and instructions specifying 1+1 minute sequential brushing (experimental); or 2) 0.76% sodium monofluorophosphate dentifrice (Colgate Cavity Protection) and instructions for twice daily use (control). Standard methods were used to measure efficacy (volatile sulfur compounds, plaque area coverage or gingival bleeding) and safety (clinical examination and interview), and to compare treatment responses.

RESULTS

Overall, 165 subjects participated in the three trials. Relative to baseline, only the experimental group exhibited significant (P< 0.05) improvements at initial and subsequent timepoints in each trial. Between-group comparisons showed significant (P< 0.05) 30-45% reductions in breath malodor (VSC), plaque (area%) and gingivitis (bleeding sites) favoring the experimental group. Adverse event occurrences were infrequent, mild in severity, and unrelated to dropout.

CLINICAL SIGNIFICANCE

Important health-related outcomes from three initial clinical trials established the feasibility of sequential brushing with a two-step 0.454% SnF₂ dentifrice and then a 3% H₂O₂ whitening gel.

A Randomized Controlled Clinical Trial to Evaluate the Efficacy of an Oscillating-Rotating Electric Toothbrush, a Stannous Fluoride Dentifrice, and Floss on Gingivitis

OBJECTIVES

To evaluate the gingival health efficacy of an oscillating-rotating electric toothbrush, a stannous fluoride dentifrice, and dental floss in adults with mild-to-moderate gingivitis.

METHODS

This was a single-center, randomized, controlled, examiner-blind, two-treatment, eight-week parallel group study in adults with at least 20 gingival bleeding sites. Eligible subjects were randomized equally to one of two groups: experimental oral hygiene group that included an Oral-B® oscillating-rotating electric toothbrush with round brush head (D20/EB20), Crest® stabilized stannous fluoride dentifrice (SnF2 1100 ppm F, NaF 350 ppm F), and Oral-B® Glide® floss; or regular oral hygiene control group that included a regular manual toothbrush (Oral-B® Indicator 35) and Crest® anti-cavity sodium fluoride dentifrice (NaF 1450 ppm F). Subjects followed manufacturer's instructions and used their assigned products over an eight-week period. Gingival health was measured at baseline, Week 4, and Week 8 using three assessments: Gingival Bleeding Index (GBI), number of bleeding sites, and Modified Gingival Index (MGI). Analysis of Covariance was used to compare gingival health between treatment groups.

RESULTS

One hundred and twenty subjects, mean age 44 years (range: 21 to 74 years), were assessed at baseline (60 per group); 113 subjects (57 in control group, 56 in experimental group) completed the study with fully evaluable data. At baseline, the groups were balanced; overall means were 0.41 for GBI, 51.7 for bleeding sites, and 1.44 for MGI. Only the experimental group showed statistically significant reductions from baseline (p < 0.0001) for all three gingivitis assessments at both Weeks 4 and 8. At these time points, better gingival health for the experimental group was seen as significantly lower adjusted mean scores versus the control group (p < 0.0001) for all three assessments. Reductions in favor of the experimental group at Weeks 4 and 8, respectively, were 51% and 45% for GBI, 46% and 40% for number of bleeding sites, and 37% and 20% for MGI. The study treatments were well tolerated.

CONCLUSIONS

Over an eight-week period, an oral hygiene routine with an oscillating-rotating electric toothbrush, stannous fluoride dentifrice, and floss significantly improved gingivitis compared to regular hygiene with a manual toothbrush and an anti-cavity sodium fluoride dentifrice.

Gingivitis Models - Relevant Approaches to Assess Oral Hygiene Products

OBJECTIVES

To review the application of gingivitis prevention and treatment models to assess the efficacy of mechanical and chemotherapeutic oral hygiene interventions following shorter- and longer-term use.

METHODS

Representative published clinical trials evaluating the shorter- and longer-term anti-gingivitis efficacy of stannous fluoride dentifrice, cetylpyridinium chloride (CPC) rinse, and oscillating-rotating (O-R) electric rechargeable toothbrushes were reviewed. Key gingivitis indices, including the Löe-Silness Gingival Index (LS), Lobene Modified Gingival Index (MGI), Gingival Bleeding Index (GBI), Papillary Bleeding Index (PIBI), and the Mazza modification of the PIBI (Mazza GI), were evaluated for their relative validity and sensitivity in evaluating prevention and treatment outcomes.

RESULTS

Twenty clinical trials were evaluated, including 11 treatment studies and 9 prevention trials. Collectively, the findings demonstrated the efficacy of stabilized stannous fluoride toothpaste, CPC rinses, and O-R electric toothbrushes in improving gingival health both in longer-term prevention and shorter-term treatment models. The studies employed various frequently used gingivitis indices. The indices were sufficiently sensitive to elucidate treatment differences.

CONCLUSIONS

Based on the results of this review, gingivitis prevention and treatment studies are valid approaches to show treatment effects, and their utilization is dependent upon whether the intention is to evaluate "reducing the onset of gingivitis" or "reducing the severity of existing gingivitis." Various indices, including the LS, MGI, GBI, PIBI, and Mazza GI indices, provide valid measurements for evaluating gingivitis in treatment and prevention models. Shorter-term treatment models allow for efficient efficacy evaluation in clinically relevant populations with existing disease.

Comparative Antiplaque Effect of Two Antimicrobial Dentifrices: Laboratory and Clinical Evaluations

OBJECTIVES

To compare the effect of a stannous fluoride dentifrice versus a triclosan-containing dentifrice on the reduction of plaque using in vitro and clinical models.

METHODS

Both investigations evaluated a novel 0.454% stabilized stannous fluoride dentifrice (Crest® Pro-Health™ smooth formula) versus a sodium fluoride/triclosan positive control dentifrice (Colgate® Total®). The in vitro evaluation utilized the Plaque Glycolysis and Regrowth Model (PGRM), wherein the metabolic effects (acid production/glycolysis inhibition) of the dentifrices were assessed on plaque biofilms grown on glass rods after three days growth and a single dentifrice treatment. Treatments were evaluated via analysis of variance, Student's t-test. The clinical trial was a four-week, single-center, randomized and controlled, double-blind, parallel group study, where 120 adults were randomized to one of the two dentifrices for use at home according to manufacturer's instructions. Plaque was evaluated at baseline and Week 4 with the Rustogi Modified Navy Plaque Index (RMNPI). Statistical analyses were via analysis of covariance.

RESULTS

In vitro PGRM: The stannous fluoride dentifrice provided 43.3% glycolysis inhibition compared to 27.5% for the triclosan control, and the pH decrease associated with acid production was significantly less for stannous fluoride (0.87) versus triclosan (1.11); p < 0.05. Clinical trial: One hundred eighteen (118) subjects completed the study with fully evaluable data. Both dentifrice groups demonstrated statistically significant (p < 0.0001) reductions in plaque at Week 4 compared with baseline, with the stannous fluoride dentifrice producing a significantly lower adjusted mean Week 4 plaque score (p < 0.0001) versus the triclosan positive control for whole mouth plaque (23.1% lower) and interproximal plaque (43.5% lower). Both dentifrices were well-tolerated.

CONCLUSIONS

The stabilized stannous fluoride dentifrice provided statistically significant reductions in plaque glycolysis in vitro and plaque growth in vivo compared to the triclosan dentifrice. Results for both studies were consistent.

In Vitro and In Vivo Evaluations of the Anticalculus Effect of a Novel Stabilized Stannous Fluoride Dentifrice

OBJECTIVES

To evaluate the effect of a novel stannous fluoride dentifrice with zinc citrate on calculus inhibition using both in vitro and clinical models.

METHODS

Each investigation tested a novel stabilized 0.454% stannous fluoride dentifrice with zinc citrate as an anticalculus agent (Crest® Pro-Health™ smooth formula) compared to a negative control fluoride dentifrice. The in vitro study used the modified Plaque Growth and Mineralization Model (mPGM). Plaque biofilms were prepared and mineralized by alternate immersion of glass rods in human saliva and artificial mineralization solution. Treatments of 25% w/w dentifrice/water slurries were carried out for 60 seconds daily for 6 days, between saliva and mineralization solution immersions. Plaque calcium levels were determined by digestion and inductively coupled plasma optical emission spectroscopy. Student's t-test (p < 0.05) was used for statistical analysis. The clinical study was a parallel group, double-blind, randomized, and controlled trial. Following a dental prophylaxis, subjects entered a two-month run-in phase. At the end, they received a Volpe-Manhold Index (V-MI) calculus examination. Eighty (80) qualified subjects who had formed at least 9 mm of calculus on the linguals of the mandibular anterior teeth were re-prophied and randomly assigned to either the stannous fluoride dentifrice or the negative control. Subjects brushed twice daily, unsupervised, during the three-month test period, returning at Weeks 6 and 12 for safety and V-MI examinations. Statistical analyses were via ANCOVA.

RESULTS

In vitro mPGM: The stabilized stannous fluoride dentifrice showed 20% less in vitro tartar formation, measured as calcium accumulation normalized by biofilm mass, versus the negative control (106.95 versus 133.04 µg Ca/mg biofilm, respectively, p < 0.05). Clinical Trial: Seventy-eight (78) subjects completed with fully evaluable data. The stannous fluoride dentifrice group had 15.1% less adjusted mean calculus at Week 6 compared to the negative control group (p = 0.05) and 21.7% less calculus at Week 12 (p < 0.01). Both dentifrices were well-tolerated.

CONCLUSIONS

The stannous fluoride dentifrice produced significant anticalculus benefits in vitro and in a clinical trial compared to a negative control.

The Case for Stabilized Stannous Fluoride Dentifrice: An Advanced Formulation Designed for Patient Preference

Oral diseases, particularly caries and gingivitis, continue to be widespread. Incorporating a stabilized stannous fluoride dentifrice into patients' daily oral hygiene routine is a convenient, cost effective approach to improve and protect their oral health and the appearance of their smile. Unlike other common fluorides that only provide anti-caries benefits (e.g., sodium fluoride and sodium monofluorophosphate), stabilized stannous fluoride formulations have demonstrated broader and significantly greater protection, also reducing plaque, gingivitis, erosion, sensitivity, and halitosis. To deliver the full range of benefits and simultaneously deliver whitening and tartar control benefits, stannous fluoride requires careful formulation. Procter & Gamble is the only dentifrice manufacturer with decades of patented innovations to overcome these formulation challenges, resulting in a large portfolio of stannous fluoride-containing dentifrice products marketed under the Crest® Pro-Health™ name that are available today. The most recent innovation is a "smooth texture" variant of Crest Pro-Health, containing stabilized stannous fluoride with zinc citrate as the anti-calculus agent. This product was developed to deliver a patient preferred brushing experience with the full range of benefits offered by Crest Pro-Health. This article discusses two common misconceptions about dentifrice, describes the history of key Crest stannous fluoride innovations, and outlines the research in this issue demonstrating health and cosmetic benefits of the new Crest Pro-Health smooth texture variant.

In-office study to evaluate the effects of a stabilized stannous fluoride dentifrice and an advanced manual toothbrush regimen on gingival health and plaque accumulation in Mexican adults

PURPOSE

This office-based study was conducted to investigate the influence of an oral hygiene regimen, consisting of a stabilized stannous fluoride dentifrice and an advanced manual toothbrush, on gingival health and plaque accumulation in Mexican adults after 4 weeks of use.

METHODS

This was an unsupervised, open-label, single-treatment, 4-week study conducted in Mexico. At Baseline, gingival health and plaque coverage were assessed for each participant by dentists using categorical scales. Participants were given 0.454% stabilized stannous fluoride dentifrice (Crest Pro-Salud Limpieza Profunda) and an advanced manual toothbrush with a CrissCross bristle design (Oral-B Pro-Salud 7 Beneficios), and were instructed to follow the manufacturer's usage instructions for the products, which state to brush after every meal, at least three times daily, or as indicated by their dentists. At the end of Week 4, plaque and gingivitis were reassessed using the same scales.

RESULTS

200 participants (age range 18 - 49 years) completed the 4-week study and were considered evaluable. The mean age of the study group was 29.9 ± 8.8 years, with 125 females and 75 males. After 4 weeks of product use, 172 participants (86%) showed noticeable improvement in their gingival health and 93% showed noticeable improvements in their overnight plaque coverage.

Assessment of hypersensitivity reduction of a dentifrice containing 0.3% triclosan, 2.0% PVM/MA copolymer, 0.243% NaF and specially-designed silica as compared to a dentifrice containing 0.454% stannous fluoride, sodium hexametaphosphate and zinc lactate and to a dentifrice containing 0.243% NaF on dentin hypersensitivity reduction: an 8-week study

PURPOSE

To evaluate the 8-week dentin hypersensitivity efficacy of three toothpastes: (1) a dentifrice containing 0.3% triclosan, 2.0% PVM/MA copolymer, 0.243% sodium fluoride and specially-designed silica (Test Dentifrice 1); (2) a commercially-available dentifrice containing 0.454% stannous fluoride in a silica base with sodium hexametaphosphate and zinc lactate (Test Dentifrice 2); and (3) a commercially-available non-sensitive dentifrice containing 0.243% sodium fluoride in a silica base (Negative Control Dentifrice).

METHODS

For this 8-week randomized controlled clinical study, qualifying subjects had to have at least two hypersensitive teeth with a tactile hypersensitivity score (Yeaple Probe) between 10 and 50 grams of force, and air blast hypersensitivity score of 2 or 3 (Schiff Cold Air Sensitivity Scale). Subjects brushed twice daily for 1 minute, using the assigned toothpaste and toothbrush. Dentin hypersensitivity assessments, as well as examinations of oral hard and soft tissues, were conducted at the baseline examination and after 4 and 8 weeks of brushing.

RESULTS

118 subjects complied with the protocol, and completed the 8-week study. At baseline, the mean tactile sensitivity scores for toothpastes (1), (2) and (3) were 13.6, 14.1 and 13.1; at 4 weeks 28.75, 20.13, and 20.00; and after 8 weeks 33.1, 24.0 and 20.5, respectively. The mean air blast scores for toothpastes (1), (2), and (3) at baseline were 2.5, 2.5, and 2.4; at 4 weeks 1.25, 1.50 and 1.85; and after 8 weeks 0.99, 1.36 and 1.5, respectively. At all time points after the baseline examination, for both tactile and air blast sensitivity scores, the differences between Test Dentifrice 1 and the Negative Control Dentifrice were statistically significant (P < 0.05). The differences between Test Dentifrice 1 and Test Dentifrice 2 were statistically significant (P < 0.05) at 4 and 8 weeks after baseline examination for tactile sensitivity scores and at 8 weeks after baseline examination for air blast sensitivity scores.

Study of safe usage of high-flow three-way stopcocks in a blood circuit

To examine the safety of using a high-flow three-way stopcock in a blood circuit during extracorporeal blood purification therapy, we studied the risk of development of hemolysis and clot formation in both ex vivo and in vivo extracorporeal circulation. In the ex vivo study, no significant difference was observed in the decrease in hematocrit (HCT) or increase in the potassium level between the three-way stopcock group and the control group. Nor was there a significant difference in the change in inlet pressure between the two groups. Thus, it was shown that the risk of hemolysis caused by the use of a high-flow three-way stopcock on both the outlet side and inlet side would be small. In the in vivo cases, there was no significant difference in the decrease in HCT or the increase in inlet pressure between the three-way stopcock group and control group, suggesting that it is clinically possible to incorporate a high-flow three-way stopcock into a blood circuit.

Oral hygiene regimens, plaque control, and gingival health: a two-month clinical trial with antimicrobial agents

OBJECTIVE

The purpose of this study was to examine the effects of various product combinations involving brush, paste, rinse, and floss on the prevention of plaque regrowth and gingivitis.

METHODOLOGY

In this randomized, parallel-group, examiner-blind, eight-week study, 179 subjects with gingivitis had a dental prophylaxis and were randomly assigned to one of six product combinations: 1) Colgate Wave manual toothbrush + Colgate Total dentifrice (0.3% triclosan/copolymer dentifrice); 2) Wave + Total + Listerine (essential oils rinse); 3) Oral-B CrossAction manual toothbrush + Crest Pro-Health dentifrice (0.454% stannous fluoride/sodium hexametaphosphate); 4) CrossAction + Pro-Health dentifrice + Crest Pro-Health Rinse (0.07% cetylpyridinium chloride rinse); 5) Oral-B ProfessionalCare Series 8000 power toothbrush + Pro-Health dentifrice; or 6) ProfessionalCare power brush + Pro-Health dentifrice + Oral-B Hummingbird power flosser. Subjects used their test products for the duration of the study. Whole mouth plaque, gingivitis, and product-related adverse events were assessed. Treatments were compared at a 0.05 level of significance.

RESULTS

One-hundred and seventy-four subjects completed the study and were included in the data analysis. At Week 8, the overnight adjusted whole mouth plaque scores were statistically significantly lower in all other groups relative to the Wave + Total group (p < or = 0.030). Plaque scores were also statistically significantly lower (approximately 20%) in both groups where a therapeutic rinse was added to a manual brush and therapeutic paste relative to scores for the brush plus paste without a rinse (p < or = 0.034). All groups showed a reduction in gingivitis at Week 4, and mean scores remained stable or increased slightly at Week 8. The power toothbrush groups were directionally better at preventing gingivitis than the manual groups at Weeks 4 and 8.

CONCLUSION

Reductions in overnight plaque were seen when therapeutic rinses were added to manual brush plus therapeutic dentifrice regimens above that observed with a manual brush and therapeutic dentifrice alone.

In vivo enamel fluoride uptake after use of fluoride products

PURPOSE

To evaluate fluoride uptake in enamel after use of products containing different fluoride components of distinct oral hygiene regimen in vivo.

METHODS

84 healthy subjects (24 females and 60 males aged 19-26 years, mean 22.2) recruited from the students attending the courses of the Medical Faculty of the University of Sassari, Italy, were randomly assigned to one of four treatments groups: A: treated with a dentifrice containing sodium monofluorophosphate (1250 ppm F-); B: treated with dentifrice with 1250 ppm F- from AmF; C: treated with an AmF toothpaste (1250 ppm F-) and a mouth rinse with 250 ppm F- from AmF; or D: treated with a NaMFP toothpaste (1250 ppm F-) plus 1250 ppm NaMFP varnish. Acid-etched enamel microbiopsies on the vestibular surface of the first maxillary premolar were collected at baseline (to), after 20 days of test product use (t1) and after 24 hours without treatment (t2). Fluoride concentration was measured using an ion-specific electrode. All measurements were made in triplicate and analyzed statistically using two-way factorial ANOVA for independent samples standard weighted-means analysis.

RESULTS

The fluoride uptake in the enamel shows a considerable variation between the groups. Significant differences were found both within all products in terms of fluoride concentration in enamel for (P < 0.0001 for two-way ANOVA, and later Tukey HSD test). After 20 days of treatment, the group using AmF toothpaste plus AmF mouthrinse had a higher fluoride uptake than the groups using either of the other products (P < 0.05). In conclusion, all products lead to an appreciable amount of fluoride uptake in enamel; AmF products led to higher concentrations. The concentration of fluoride accumulated during treatment phase remained high after 24 hours following the cessation of use.

[Labeling of leukocytes using stannous 99mTc-colloid in whole blood samples]

This paper presents the preparation of a radiocolloid that still makes it possible to label leukocytes using its phagocytosis capacity. Given that this function is exclusively of the white blood cells, not being exercised by other blood cells, the use of a stannous fluoride radiocolloid labeled with 99mTc (F2Sn-99mTc) was tested in order to label leukocytes in whole blood samples. Using cellular separation techniques in density gradients and acquisition of images in gamma camera of radioactivity distribution in Percol, it was observed that the white cells labeling achieved was selective and with high efficiency for leukocytes (in all cases, it was superior to 70%), optimal reproducibility, low cost and low cellular toxicity.

Fluoride: a review--Part II: Topical fluorides

Fluoride therapy continues to be the best defense in the battle against dental caries. The decision to utilize topical fluorides is no longer age dependent. Changing disease patterns require dentists to critically evaluate the caries risk of each patient and develop a fluoride treatment plan based upon the needs of the individual patient. A variety of professional and self-applied fluoride products are available and new fluoride delivery systems have recently entered the market. A critical review of literature, combined with an understanding of the advantages and disadvantages of each topical fluoride system will assist the dentist in selecting the product best suited for each patient.

Splenic function in sickle cell anemia patients in Qatif, Saudi Arabia

A prospective study was conducted to study the splenic function among sickle cell anemia (SCA) patients in Qatif (Eastern Province of Saudi Arabia). Seventy-seven patients (30 children and 47 adults aged 2-57 years) were included. (99m)Tc stannous colloid liver-spleen scan was done for each patient during steady state. The splenic function was graded from 0 to 4 in relation to liver uptake. Seventy percent of our patients showed evidence of splenic hypofunction, and most of them (83%) had severe hyposplenism. Up to the age of 4 years, only 17% of the children showed evidence of functional hyposplenism, but by the age of 10 years >50% were hyposplenic. Most of the hyposplenic children had functional hyposplenism, whereas only one-third of hyposplenic adults had autosplenectomy. There was no effect of level of HbF on the frequency of hyposplenism, but on the other hand low MCV seems to be protective against hyposplenism. A significant number of adult SCA patients have clinically enlarged spleens, and almost a third have normally functioning spleens. Because of the low prevalence of hyposplenism in children younger than 4 years of age, routine penicillin prophylaxis is probably not indicated in this population, an issue which needs further evaluation.