A randomised clinical evaluation of a fluoride mouthrinse and dentifrice in an in situ caries model

The use of mouthwash containing trimetaphosphate as an adjunct therapy to fluoridated toothpaste reduces enamel demineralization

INTRODUCTION

The decline in dental caries has been attributed to the widespread use of fluoride (F). Two forms of presentation are fluoridated toothpaste (FT) and mouthwash (MW), widely used by the population.

MATERIALS AND METHODS

This study aimed to evaluate in vitro the effects of combining FT and MW, whether supplemented with sodium trimetaphosphate (TMP) or not, on dental enamel demineralization. Bovine enamel blocks (n = 60) were selected based on initial surface hardness (SHi) and divided into 5 experimental groups (n = 12 each): I) Placebo Toothpaste (without F/TMP); II) 1100 ppm F Toothpaste (FT); III) 1100F associated with a MW at 100 ppm F (FT + MW 100F); IV) 1100F associated with a MW at 225 ppm F (FT + MW 250F); and V) 1100F associated with a MW at 100 ppm F supplemented with 0.4 % TMP (FT + MW 100F-TMP). The blocks were treated twice a day, undergoing 5 pH cycles over 7 days. Thus, the percentage change in surface hardness (%SH), integrated subsurface hardness loss (ΔKHN), and the concentration of F, phosphorus (P), and calcium (Ca) in the enamel were determined. The data were submitted to ANOVA and Student-Newman-Keuls test (p < 0.001).

RESULTS

The 1100F group was statistically inferior to the groups associated with MW for %SH, ΔKHN, and the concentration of P and Ca in the enamel (p < 0.001). Blocks treated with FT + MW 225F and FT + MW 100F-TMP showed significantly lower %SH compared to the other groups (p < 0.001). The FT + MW 100F - TMP group exhibited the lowest depth mineral loss (ΔKHN), and higher concentration de P in enamel (p < 0.001).

CONCLUSION

The adjunct use of MW with FT produces a greater protective effect in inhibiting enamel demineralization, and the supplementation of TMP to the MW with 100F provides a superior effect compared to MW with 225F.

CLINICAL SIGNIFICANCE

This combination of treatments could be regarded as one of several alternative fluoride supplements for subjects at elevated risk of caries.

Preparation and characterization of NaF/Chitosan supramolecular complex and their effects on prevention of enamel demineralization

Fluoridated mouthrinse is indicated for individuals with high risk of caries. Chitosan (Chit) exhibits antibacterial properties, but little is known about its effects on enamel when combined with sodium fluoride (NaF) to form NaF/Chit supramolecular complexes. In our study, NaF/Chit supramolecular complexes structured as microparticles were synthetized and characterized, and their effects on human enamel were evaluated after cariogenic challenge simulating the daily mouthrinse use. Initially, NaF/Chit complex formation was investigated based on several titrations by measuring the zeta potential, electrical conductivity (κ), hydrodynamic diameter (Dh), viscosity (η) and heat flow (by isothermal titration calorimetry) against the molar ratio [NaF]/[Chitmonomer], which allowed us to identify the interactions between Chit-NaF with a stoichiometry of approximately 0.68. Spontaneous microparticle formation was observed. Samples of enamel blocks were prepared and divided into eight groups (n = 10/group): (i) 0.2% Chit; (ii) 0.2% NaF; (iii) 0.2% NaF/Chit suspension; (iv) 0.2% acetic acid; (v) 0.05% Chit; (vi) 0.05% NaF; (vii) 0.05% NaF/Chit suspension; and (viii) 0.05% acetic acid. Cariogenic challenge was performed in each sample by cycling in demineralization and remineralization solutions for 7 days. Before each demineralization cycle, the corresponding substances were passively applied daily for 90 s, even in groups with 0.02% concentration. After 7 days, samples were examined for Knoop hardness (KHN) measurements. The data were analyzed by repeated-measures ANOVA and Tukey tests (α = 0.05). The 0.2% NaF and 0.2% NaF/Chit groups showed higher KHNpost-challenge values than the other groups. The 0.2% NaF/Chit microparticle suspension reduced the enamel hardness loss after cariogenic challenge as effectively as the 0.2% NaF solution and demonstrated potential for use in a formulation with anti-caries effects.

Short-term anti-plaque effect of a cymenol mouthwash analysed using the DenTiUS Deep Plaque software: a randomised clinical trial

BACKGROUND

The effect of cymenol mouthwashes on levels of dental plaque has not been evaluated thus far.

OBJECTIVE

To analyse the short-term, in situ, anti-plaque effect of a 0.1% cymenol mouthwash using the DenTiUS Deep Plaque software.

METHODS

Fifty orally healthy participants were distributed randomly into two groups: 24 received a cymenol mouthwash for eight days (test group A) and 26 a placebo mouthwash for four days and a cymenol mouthwash for a further four days thereafter (test group B). They were instructed not to perform other oral hygiene measures. On days 0, 4, and 8 of the experiment, a rinsing protocol for staining the dental plaque with sodium fluorescein was performed. Three intraoral photographs were taken per subject under ultraviolet light. The 504 images were analysed using the DenTiUS Deep Plaque software, and visible and total plaque indices were calculated (ClinicalTrials ID NCT05521230).

RESULTS

On day 4, the percentage area of visible plaque was significantly lower in test group A than in test group B (absolute = 35.31 ± 14.93% vs. 46.57 ± 18.92%, p = 0.023; relative = 29.80 ± 13.97% vs. 40.53 ± 18.48%, p = 0.024). In comparison with the placebo, the cymenol mouthwash was found to have reduced the growth rate of the area of visible plaque in the first four days by 26% (absolute) to 28% (relative). On day 8, the percentage areas of both the visible and total plaque were significantly lower in test group A than in test group B (visible absolute = 44.79 ± 15.77% vs. 65.12 ± 16.37%, p < 0.001; visible relative = 39.27 ± 14.33% vs. 59.24 ± 16.90%, p < 0.001; total = 65.17 ± 9.73% vs. 74.52 ± 13.55%, p = 0.007). Accounting for the growth rate with the placebo mouthwash on day 4, the above results imply that the cymenol mouthwash in the last four days of the trial reduced the growth rate of the area of visible plaque (absolute and relative) by 53% (test group A) and 29% (test group B), and of the area of total plaque by 48% (test group A) and 41% (test group B).

CONCLUSIONS

The 0.1% cymenol mouthwash has a short-term anti-plaque effect in situ, strongly conditioning the rate of plaque growth, even in clinical situations with high levels of dental plaque accumulation.

Longitudinal In Vitro Effects of Silver Diamine Fluoride on Early Enamel Caries Lesions

This laboratory study evaluated the longitudinal surface microhardness changes in early, incipient, noncavitated, white-spot, enamel caries lesions treated with silver diamine fluoride (SDF). Five intervention groups (SDF, AgNO3, KF, 5% sodium fluoride varnish (FV), deionized water (DI)) × two-time intervals after intervention (immediate & delayed pH-cycling) resulted in 10 groups (n=18). Silver nitrate (AgNO3) and potassium fluoride (KF) groups served as controls to assist in evaluating if remineralization effects were due to the silver or fluoride component in SDF. Early, incipient, noncavitated, white-spot, enamel caries lesions were created in bovine enamel, the extent of demineralization was determined using Vickers surface microhardness (VHNlesion). Intervention treatments were applied. Half the specimens from each group underwent immediate 5-day pH-cycling, and half were stored in an incubator with artificial saliva for 2 weeks before undergoing 5-day pH-cycling. After pH-cycling, lesion hardness was evaluated using VHNpost. Specimens were then exposed to a second demineralization challenge, and lesion softening was evaluated (VHNsecdem). Hardness variables were calculated: ΔVHN = VHNpost - VHNlesion; ΔVHNsecdem = VHNsecdem - VHNpost. Data were analyzed using two-way ANOVA (α=0.05). Immediately cycled, SDF had significantly (p<0.0001) greater remineralization than DI, AgNO3, and FV. All delayed cycling groups had significantly greater remineralization than FV (p<0.0001). Significantly greater remineralization was noted in delayed AgNO3 (p≤0.0001), DI (p=0.0003), and FV (p=0.0006) compared to immediately cycled. After the second demineralization challenge, FV had significantly less surface softening than AgNO3 (p=0.0002), DI (p=0.0003), KF (p=0.0225), and SDF (p=0.0388) intervention groups. No significant difference was found between the pH-cycle timings (p=0.2710). Based the present findings, FV may be better suited than SDF to treat early, incipient, noncavitated, white-spot, enamel caries lesions.

The effect of fluoride iontophoresis on seal ability of self-etch adhesive in human dentin in vitro

Background

Fluoride iontophoresis (FI) is a non-invasive method for the transfer of fluoride ions under electrical pressure into dental hard tissue. This study aimed to determine the effect of FI on the seal ability of self-etch adhesive in human dentin using dentin permeability test and scanning electron microscopy (SEM).

Methods

The experiments were divided into 2 series: series 1 was performed on 28 extracted intact third molars and series 2 was performed on 28 extracted carious third molars (ICDAS 4 and 5). In each series, 20 teeth were used for dentin permeability test and 8 teeth were used for SEM study. For dentin permeability test, the specimens were divided into dentin without FI (control) and dentin with FI (experimental) subgroups. Hydraulic conductance (HD) of dentin was measured before and after adhesive treatment, and calculated for the percentage decrease of HD in each subgroup. Two-way ANOVA and Tukey test were used for statistical analysis. SEM study was used to assess the seal ability of self-etch adhesive and penetration of fluoride ions into dentinal tubules.

Results

HD after self-etch adhesive treatment reduced by 57.75 ± 17.99% in intact dentin with FI, 46.60 ± 17.03% in intact dentin without FI, 45.00 ± 15.30% in caries affected dentin without FI, and 37.28 ± 14.72% in caries affected dentin with FI. There was no significant difference in percentage decrease of HD between dentin without FI and dentin with FI (P = 0.742); meanwhile, intact dentin with FI had significant greater percentage decrease than caries affected dentin with FI (P < 0.05). SEM findings showed FI produced more particle formation and deeper precipitation in intact dentin than those in caries affected dentin.

Conclusions

FI did not affect the seal ability of self-etch adhesive in human dentin when compared to without FI. However, FI could augment the seal ability of the self-etch adhesive in intact dentin better than that in caries affected dentin.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12903-022-02146-w.

An Extensive Comparison of the Clinical Efficiency of Acidulated Phosphate Fluoride (APF) and Neutral Sodium Fluoride (NaF) Oral Rinses in the Prevention of White Spot Lesions during Fixed Orthodontic Treatment: A Randomized Controlled Trial

Background

The purpose of this randomized trial is to compare the efficacy of weekly once regime of neutral sodium fluoride (NaF) oral rinse with that of acidulated phosphate (APF) formulated daily mouth rinse in the reduction of white spot lesions (WSLs) associated with fixed orthodontic appliance treatment.

Methods

The participants (n = 90) of this single-center, two-arm parallel study without a control group were randomly assigned with 1 : 1 distribution to each of the two groups after the bonding of brackets. Group A/test group 1 (n = 45) was given weekly rinse of neutral sodium fluoride (Colgate® PreviDent® Dental Rinse-0.2% NaF), and for group B/test group 2 (n = 45), an APF formulated daily oral rinse (Colgate® Ortho Defense^@ PhosFlur® Rinse-0.044% w/v of NaF) was given for six months. The outcome was assessed by the International Caries Detection and Assessment System (ICDAS) index for scoring the demineralization, and for scoring gingivitis, Loe and Silness gingival index (GI) was utilized. Four different time points “T0”immediately before bonding procedures, “T1” after 4weeks, “T2” after 12 weeks, and “T3” after 24 weeks were taken to assess the ICDAS and GI scores.

Results

The mean ICDAS scores for group A (NaF) were 0.025, 0.051, 0.093, and 0.113 and for group B (APF) were 0.014, 0.022, 0.038, and 0.015 at different points of time. The GI scores for group A were 0.008, 0.22, 0.33, and 0.38 and for group B were 0.003, 0.136, 0.181, and 0.097 at different time points. There was a statistically significant difference (p < 0.05) for both groups in terms of reducing WSL and GI.

Conclusion

APF formulated daily oral rinse—0.044% w/v of NaF—is more effective than the weekly once regimen of 0.2% NaF oral rinse to prevent white spot lesions.

Effects of health-promoting school strategy on dental plaque control and preventive behaviors in schoolchildren in high-caries, rural areas of Taiwan: a quasi-experimental design

Background

We evaluated the effects of health-promoting school (HPS) strategy on plaque control and behavior change in high-caries schoolchildren in Taitung, Taiwan.

Methods

A quasi-experimental design was adopted; six intervention schools (intervention group [IG]) and six comparison schools (comparison group [CG]) were selected from elementary schools with higher-than-average caries rates (> 68%). The IG was selected using cluster sampling, and the CG was selected to match the IG. In total, the IG and CG groups included 166 and 174 children each. The selected schools implemented the HPS framework for 3 months in the 2019 academic year. An oral examination of dental plaque was administered, and a self-administered questionnaire regarding knowledge, attitude, self-efficacy, and behaviors was distributed at baseline and at 2-week follow-up. A linear and logistic regression model using generalized estimating equations (GEEs) was used to analyze the differences between baseline and the follow-up data.

Results

Compared with the CG, the IG had a greater reduction in plaque index among second graders (β =  − 0.36) and plaque control record scores among second, fourth, and sixth graders (β =  − 27.48, − 26.04, and − 18.38, respectively). The IG also exhibited a greater increase at follow-up with respect to oral health–related knowledge among second graders and fourth graders (β = 1.46 and β = 0.92, respectively), attitude toward oral hygiene behaviors among sixth graders (β = 1.78), and self-efficacy regarding flossing for sixth graders (β = 1.43). Sixth graders in the IG were significantly more likely to brush before sleeping (adjusted odds ratio [aOR] = 2.99) and use fluoride toothpaste (aOR = 5.88) than those in the CG.

Conclusions

The HPS strategy was effective in reducing dental plaque and promoting preventing behaviors in rural high-caries schoolchildren.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12903-021-01927-z.

Synthesis of a chitosan nanoparticle suspension and its protective effects against enamel demineralization after an in vitro cariogenic challenge

Objective

Our study aims to synthesize, characterize, and determine the effects of a ChNPs suspension on human enamel after cariogenic challenge via pH-cycling.

Methodology

ChNPs were synthesized by ion gelation and characterized by Transmission Electron Microscopy (TEM) and Dynamic Light Scattering. Forty enamel blocks were divided into four groups (n=10/group): (i) ChNPs suspension; (ii) chitosan solution; (iii) 0.05% sodium fluoride (NaF) solution; and (iv) distilled water. Specimens were exposed to cariogenic challenge by cycling in demineralization solution (3 h) and then remineralized (21h) for 7 days. Before each demineralization cycle, the corresponding solutions were passively applied for 90 s. After 7 days, specimens were examined for surface roughness (Ra) and Knoop hardness (KHN) before and after the cariogenic challenge; % KHN change (variation between initial and final hardness), and surface topography by an optical profilometer. The data were analyzed by repeated-measures ANOVA, One-way ANOVA, and Tukey tests (α=0.05).

Results

TEM images showed small spherical particles with diameter and zeta potential values of 79.3 nm and +47.9 mV, respectively. After the challenge, all groups showed an increase in Ra and a decrease in KHN values. Optical profilometry indicated that ChNPs- and NaF-treated specimens showed uneven roughness interspersed with smooth areas and the lowest %KHN values.

Conclusion

The ChNPs suspension was successfully synthesized and minimized human enamel demineralization after a cariogenic challenge, showing an interesting potential for use as an oral formulation for caries prevention.

The Current Strategies in Controlling Oral Diseases by Herbal and Chemical Materials

Dental plaque is a biofilm composed of complex microbial communities. It is the main cause of major dental diseases such as caries and periodontal diseases. In a healthy state, there is a delicate balance between the dental biofilm and host tissues. Nevertheless, due to the oral cavity changes, this biofilm can become pathogenic. The pathogenic biofilm shifts the balance from demineralization-remineralization to demineralization and results in dental caries. Dentists should consider caries as a result of biological processes of dental plaque and seek treatments for the etiologic factors, not merely look for the treatment of the outcome caused by biofilm, i.e., dental caries. Caries prevention strategies can be classified into three groups based on the role and responsibility of the individuals doing them: (1) community-based strategy, (2) dental professionals-based strategy, and (3) individual-based strategy. The community-based methods include fluoridation of water, salt, and milk. The dental professionals-based methods include professional tooth cleaning and use of varnish, fluoride gel and foam, fissure sealant, and antimicrobial agents. The individual-based (self-care) methods include the use of fluoride toothpaste, fluoride supplements, fluoride mouthwashes, fluoride gels, chlorhexidine gels and mouthwashes, slow-release fluoride devices, oral hygiene, diet control, and noncariogenic sweeteners such as xylitol. This study aimed to study the research in the recent five years (2015–2020) to identify the characteristics of dental biofilm and its role in dental caries and explore the employed approaches to prevent the related infections.

Salivary fluoride concentration and retention after rinsing with 0.05 and 0.2% sodium fluoride (NaF) compared with a new high F rinse containing 0.32% NaF

OBJECTIVE

To compare salivary fluoride (F) concentration and F retention after rinsing with a new 0.32% sodium fluoride (NaF) rinse and conventional 0.05 and 0.2% NaF rinses.

METHODS

Seventeen subjects (aged 22-26 years), with normal salivary secretion rates, participated in a double blind, cross-over study. In three separate sessions with a minimum washout period of 48 h, they rinsed for 1 min with 10 ml of 0.05, 0.2 or 0.32% NaF mouthrinse. Unstimulated whole saliva was collected before (baseline: 0 min) and after 1, 3, 5, 10, 20, 30, 45 and 60 min. The F concentration was plotted against time, and the area under the curve (AUC) calculated. Salivary F concentration and F retention for the three mouthrinses were compared by a randomized block test, followed by Tukey's test and a paired 2-tailed test.

RESULTS

There was a clear dose-response for AUC 3-60 min; 0.32% > 0.2% > 0.05% (p < .05). The mean F retention was 0.25 mg for 0.05% NaF, 0.86 mg F for 0.2% Na and 1.31 mg F for 0.32% NaF, (p < .05).

CONCLUSIONS

The higher salivary F concentration over time and the higher F retention after rinsing with an 0.32% NaF solution suggests a potential application in prevention of caries and dental erosion.