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Cited by 74Dental Health and Care UtilizationOral microbiology and periodontitis researchDental Erosion and Treatment

The DOI matches its Crossref record; 61 of the 61 references it cites were found in a registry or an index; none of the 68 sources its claims cite is checked for support yet.

Validation of a Cariogenic Biofilm Model to Evaluate the Effect of Fluoride on Enamel and Root Dentine Demineralization

Open access
Fernández, Constanza E., Tenuta, Livia M. A., Cury, Jaime A.·2016·PLOS ONE
DOI 10.1371/journal.pone.0146478PMC PMC4712139
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Abstract

Due to gingival recession both enamel and root dentine are at risk of developing caries. Both tissues are exposed to a similar environment, however there is not a validated model to evaluate the effect of fluoride on these dental substrates simultaneously. Hence, this study aimed to validate a caries model to evaluate the effect of fluoride to prevent demineralization on enamel and root-dentine. Streptococcus mutans UA159 biofilms were formed on saliva-coated bovine enamel and root dentine slabs (n = 12 per group) mounted in the same well of culture plates. The biofilms were exposed 8×/day to 10% sucrose and treated 2×/day with fluoridated solutions containing 0, 150, 450, or 1,350 ppm F; thus, simulating the use of low to high fluoride concentration toothpastes. The pH values of the culture medium was monitored 2×/day as a biofilm acidogenicity indicator. After 96 h, biofilms were collected for fluoride concentration analysis. The percentage of surface hardness loss (%SHL) was calculated for slabs. The fluoride uptake by the enamel and dentine was also determined. The model showed a dose-response because the biofilm and fluoride uptake increased and %SHL decreased at increasing fluoride concentrations (p < 0.05). Fluoride in the biofilm formed on dentine and fluoride uptake by dentine were higher than those for enamel. With the same fluoride concentration treatment, the percentage of reduction of demineralization was lower for dentine than for enamel. In conclusion, the model was validated in terms of a dose-response effect of fluoride on enamel and root dentine. Furthermore, the findings support the clinical data, suggesting that higher fluoride concentrations are necessary to control caries of root dentine than of enamel.

Overview

AI snapshot

Written from the paper’s full text.

TL;DR

This study validated a 96-h *Streptococcus mutans* biofilm model for simultaneously evaluating fluoride effects on enamel and root dentine demineralization. The model showed a fluoride dose-response on both substrates, but dentine required about 3× higher fluoride than enamel to achieve a similar demineralization reduction.

Key findings

  • Fluoride treatment produced a dose-response effect on both enamel and root dentine: increasing fluoride concentration increased biofilm fluoride and fluoride uptake and decreased percentage surface hardness loss (%SHL) (p < 0.05).
  • Demineralization was consistently higher in dentine than enamel across groups; in the non-fluoride control, dentine showed approximately 49% demineralization versus 29% for enamel.
  • Reduction of demineralization versus control was 46.8% for enamel and 21.3% for dentine at 150 ppm F; 60.9% and 36.9% at 450 ppm F; and 76.1% and 58.8% at 1,350 ppm F. A similar ~60% reduction occurred with 450 ppm F for enamel and 1,350 ppm F for dentine.
  • Fluoride concentration in dentine was higher than in enamel at all treatments, e.g. 1,105 ± 331 vs. 256.4 ± 65.8 μg F/g at 0 ppm F and 6,133 ± 1,280 vs. 760.7 ± 241.9 μg F/g at 1,350 ppm F.

Methods

  • *S. mutans* UA159 biofilms were grown for 96 h on saliva-coated bovine enamel and root dentine slabs mounted in the same well; slabs were exposed 8×/day to 10% sucrose and treated 2×/day with NaF solutions containing 0, 150, 450, or 1,350 ppm F, simulating toothpastes of 0, 500, 1,100, and 5,000 ppm F after 1:3 saliva dilution.
  • The study was conducted in three independent assays (n = 12/substrate/group); outcomes included medium pH, F, and Ca; biofilm soluble and bound F; slab %SHL; and fluoride uptake by enamel and dentine.
  • Data were analyzed by two-way ANOVA with factors substrate and fluoride concentration, plus regression analyses between %SHL and fluoride concentration; significance was set at 5%.

Limitations

  • The paper states that using a single-species biofilm could be considered a limitation, although it argues that in vitro models cannot simulate the hundreds of species in dental biofilm and that this model was developed specifically for fluoride effects on enamel and root caries.
  • The text makes evident that the model is in vitro, uses bovine enamel and root dentine slabs, and uses saliva from a single healthy donor per experiment, so findings may not fully represent human clinical conditions.
  • The paper notes that fluoride concentrations in biofilm and medium were below 10 ppm, the minimum concentration reported to inhibit enolase, and that biofilm weight and acidogenicity did not differ among treatments; thus the model primarily captures physicochemical fluoride effects rather than antimicrobial effects.

Model-written summary. Check it against the paper before relying on it.

Integrity signals

Registry

Crossref · 10.1371/journal.pone.0146478

Cites

61 of 61 references verified0 citation errors · 0 not checkable

Statistics

Nothing to recompute.

Verification

Claims the paper makes

0 of 68 cited sources checked · 0 supported · 0 flagged

  • Findingown data

    The data of soluble fluoride found in biofilm support the dose-response effect of fluoride concentration on demineralization in either enamel or dentine.

    “The data of soluble fluoride found in biofilm (Table 3) also give support to the dose-response effect of fluoride concentration on demineralization in either enamel or dentine (Fig 2).”
    Quote in the paperSubstantial claim
  • Findingown data

    Fluoride concentrations in biofilm treated with the greatest concentration used or in the culture medium were below 10 ppm, the minimum fluoride concentration to inhibit enolase.

    “fluoride concentrations either in biofilm treated with the greater concentration used (Table 3) or in the culture medium (Fig 3B) were below 10 ppm, the minimum fluoride concentration to inhibit enolase [51].”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [51] DJ Bradshaw, 2002, Effects of glucose and fluoride on competition and metabolism within in vitro dental bacterial communities and biofilms, Caries Res source
  • Findingown data

    Our findings show that dentine gains more fluoride than enamel during the dynamics of the caries process.

    “but our findings show that dentine also gains more fluoride than enamel during the dynamics of the caries process (Fig 2).”
    Quote in the paperSubstantial claim
  • Findingown data

    Calcium concentration in the culture medium decreased with increasing fluoride concentration of the treatments.

    “F and Ca concentration in the culture medium (Fig 3) showed distinct patterns with fluoride concentration of the treatments, i.e., while fluoride increased, calcium decreased.”
    Quote in the paperNot a substantial claim
  • Findingown data

    We did not find an effect of fluoride concentration on biofilm weight and acidogenicity.

    “In fact, we did not find an effect of fluoride concentration on biofilm weight and acidogenicity, even when these are not at direct measured of microbial viability.”
    Quote in the paperSubstantial claim
  • It may state two separate claims as one. 20
  • Probably not a substantial claim. 15

  • It may state two separate claims as one.

    Findingown data

    The results from fluoride concentration in the medium showed a pattern different from Ca and reflect the concentration of fluoride treatments.

    “The results from fluoride concentration in the medium (Fig 3B) showed a pattern different from Ca and reflects the concentration of fluoride treatments.”
    Quote in the paperNot a substantial claim
    • Rests on an assumption: Ca is a chemical indicator of enamel and dentine demineralization.

  • It may state two separate claims as one.

    Findingown data

    A dose-response effect was seen for both dental substrates with a negative linear relationship between %SHL and fluoride concentrations of the treatments.

    “In terms of the effect of the treatments on enamel and dentine demineralization (Fig 2), a dose-response effect was seen for both dental substrates with a negative linear relationship between %SHL and fluoride concentrations of the treatments.”
    Quote in the paperSubstantial claim

  • It may state two separate claims as one.

    Findingown data

    Fluoride concentrations in biofilm formed on dentine by fluoride treatments were higher than those on enamel and statistically significant for the treatments with the highest fluoride concentration.

    “Fluoride concentrations in biofilm formed on dentine by fluoride treatments were higher than those on enamel and statistically significant for the treatments with the highest fluoride concentration (Table 3).”
    Quote in the paperNot a substantial claim

  • It may state two separate claims as one.

    Findingown data

    Ca concentration in the medium after the 8 sucrose exposures was higher in the control group, where greater %SHL was found.

    “its concentration in the medium after the 8 sucrose exposures (demineralization period, times of 32, 56, and 80 h) was higher in the control group, where greater %SHL was found.”
    Quote in the paperSubstantial claim
    • Rests on an assumption: Ca is a chemical indicator of enamel and dentine demineralization.

  • It may state two separate claims as one.

    Findingown data

    After the overnight remineralization period, the difference between the groups decreased but the trend was maintained.

    “After the overnight remineralization period, when the biofilm stayed immerse in neutral medium for 48, 72, and 96 h, the difference between the groups decreased but the trend was maintained (Fig 3A).”
    Quote in the paperNot a substantial claim
    • Rests on an assumption: Ca is a chemical indicator of enamel and dentine demineralization.

  • It may state two separate claims as one.

    Findingown data

    In enamel, 450 ppm F produced a 60% reduction in demineralization, whereas in dentine the same percentage reduction was obtained only with 1,350 ppm F.

    “Thus, while 450 ppm F produced a 60% reduction in demineralization of enamel, in dentine this effect at the same percentage could only be obtained with 1,350 ppm F.”
    Quote in the paperSubstantial claim

  • It may state two separate claims as one.

    Premisecitation

    Caries progress is faster in dentine than in enamel, and under the same cariogenic challenge dentine is more susceptible to demineralization than enamel.

    “Nevertheless, caries progress is faster in dentine than in enamel [4] because dentine has a higher organic matrix percentage [5], higher permeability [6], and smaller crystals with higher carbonate concentration [7], resulting in a higher critical pH for dentine than for enamel demineralization [8–10].”
    • Also stated in: § Introduction · hedged
      “Therefore, under the same cariogenic challenge, dentine should be considered more susceptible to demineralization than enamel.”
    Quote in the paperSubstantial claim0 of 4 sources checked
    • cites [4] B Ogaard, 1988, In vivo progress of enamel and root surface lesions under plaque as a function of time, Caries Res source
    • cites [8] PM Hoppenbrouwers, 1986, The vulnerability of unexposed human dental roots to demineralization, J Dent Res source
    • cites [9] JS Wefel, 1994, Root caries histopathology and chemistry, Am J Dent
    • cites [10] RP Shellis, 2010, Formation of caries-like lesions in vitro on the root surfaces of human teeth in solutions simulating plaque fluid, Caries Res source

  • Probably not a substantial claim.

    Premisecitation

    Fluoride is the main strategy for non-invasive control of root caries.

    “Fluoride is still the main strategy for non-invasive control of root caries [11].”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [11] RJ Wierichs, 2014, Systematic Review on Noninvasive Treatment of Root Caries Lesions, J Dent Res source

  • Probably not a substantial claim. The paper’s conclusions may not depend on it. It may state two separate claims as one.

    Study design and conductnone given

    The study was conducted in three independent assays (n = 12/substrate/group) and response variables were blindly analyzed.

    “The study was conducted in three independent assays (n = 12/substrate/group) and response variables were blindly analyzed.”
    Quote in the paperNot a substantial claim

  • It may state two separate claims as one.

    Interpretationreasoning

    This model could be used to estimate the anti-caries potential of innovative toothpaste formulations with low fluoride concentration that could be recommended to control enamel caries in children, and formulations with high fluoride concentrations that have been suggested to control root caries in elderly people.

    “Therefore, this model could be used to estimate the anti-caries potential of innovative toothpaste formulations with low fluoride concentration [46] that could be recommended to control enamel caries in children, and formulations with high fluoride concentrations, that have been suggested to control root caries in elderly people [19, 21, 22].”
    Quote in the paperSubstantial claim0 of 4 sources checked
    • cites [46] HM Negri, 2002, Dose-response effect of a dentifrice formulation with low fluoride concentration—an in vitro study, Pesqui Odontol Bras
    • cites [19] A Baysan, 2001, Reversal of primary root caries using dentifrices containing 5,000 and 1,100 ppm fluoride, Caries Res source
    • cites [21] M Srinivasan, 2014, High-fluoride toothpaste: a multicenter randomized controlled trial in adults, Community Dent Oral Epidemiol source
    • cites [22] KR Ekstrand, 2013, A randomized clinical trial of the anti-caries efficacy of 5,000 compared to 1,450 ppm fluoridated toothpaste on root caries lesions in elderly disabled nursing home residents, Caries Res source

  • It may state two separate claims as one.

    Premisecitation

    S. mutans is considered the most cariogenic bacteria in dental biofilm and it presents unique properties to metabolize sucrose, the most cariogenic dietary carbohydrate.

    “S. mutans is considered the most cariogenic bacteria in dental biofilm and it presents unique properties to metabolize sucrose, the most cariogenic dietary carbohydrate [54, 55].”
    Quote in the paperSubstantial claim0 of 2 sources checked
    • cites [54] WJ Loesche, 1986, Role of Streptococcus mutans in human dental decay, Microbiol Rev source
    • cites [55] RG Quivey Jr., 2000, Adaptation of oral streptococci to low pH, Adv Microb Physiol source

  • Probably not a substantial claim.

    Study design and conductnone given

    Slabs with intra-variability of SH lower than 10% were selected.

    “Slabs with intra-variability of SH lower than 10% were selected.”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim. The paper’s conclusions may not depend on it.

    Premisecitation

    For dentine, combination of methods of fluoride delivery is necessary to control caries.

    “For dentine, higher fluoride concentration [19–23], higher frequency of use [24], or combination of methods of fluoride delivery [25] should be necessary to control caries; however, the evidence is not conclusive.”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [25] GC Vale, 2011, APF and dentifrice effect on root dentin demineralization and biofilm, J Dent Res source

  • Probably not a substantial claim. The paper’s conclusions may not depend on it.

    Premisecitation

    The recommendation of toothpaste is based on strong evidence.

    “Among all methods of fluoride delivery, toothpaste is responsible for the decline of coronal caries [12, 13] and its recommendation is based on strong evidence [14, 15].”
    Quote in the paperNot a substantial claim0 of 2 sources checked
    • cites [14] T Walsh, 2010, Fluoride toothpastes of different concentrations for preventing dental caries in children and adolescents, Cochrane Database Syst Rev

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

    • cites [15] VC Marinho, 2003, Fluoride toothpastes for preventing dental caries in children and adolescents, Cochrane Database Syst Rev

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • It may state two separate claims as one.

    Interpretationown data

    The findings consistently showed that this biofilm model is valid to evaluate the effect of fluoride in either enamel or dentine demineralization, or simultaneously in both.

    “In summary, the findings consistently showed that this biofilm model is valid to evaluate the effect of fluoride in either enamel or dentine demineralization, or simultaneously in both.”
    Quote in the paperSubstantial claim
    • Rests on an assumption: This cariogenic biofilm model has not been validated in terms of dose-response to evaluate the effect of fluoride on either enamel or dentine.

  • It may state two separate claims as one.

    Study design and conductreasoning

    Our model simulated the caries process because the biofilms were treated 8×/day with sucrose, when enamel and dentine were simultaneously subjected to demineralization, and during the night the slabs were subjected to remineralization because the biofilms were not treated with sucrose, and the pH was maintained around neutral values.

    “Our model simulated the caries process because the biofilms were treated 8×/day with sucrose, when enamel and dentine were simultaneous subjected to demineralization, and during the night the slabs were subjected to remineralization because the biofilms were not treated with sucrose, and the pH was maintained around neutral values.”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim. The paper’s conclusions may not depend on it.

    Premisecitation

    Toothpaste is responsible for the decline of coronal caries.

    “Among all methods of fluoride delivery, toothpaste is responsible for the decline of coronal caries [12, 13] and its recommendation is based on strong evidence [14, 15].”
    Quote in the paperNot a substantial claim0 of 2 sources checked
    • cites [12] D Bratthall, 1996, Reasons for the caries decline: what do the experts believe?, Eur J Oral Sci source
    • cites [13] JA Cury, 2004, The importance of fluoride dentifrices to the current dental caries prevalence in Brazil, Braz Dent J source

  • Probably not a substantial claim. The paper’s conclusions may not depend on it.

    Premisecitation

    Dentine is more reactive to fluoride than enamel.

    “It is well known that dentine is more reactive to fluoride than enamel [20]”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [20] JM ten Cate, 1995, pH-cycling of enamel and dentin lesions in the presence of low concentrations of fluoride, Eur J Oral Sci source

  • It may state two separate claims as one.

    Interpretationreasoning

    The findings support the knowledge that the mechanism of action of fluoride on caries control is local and the antimicrobial effect of fluoride may be marginal when compared with the physicochemical effect.

    “The findings gives support to the knowledge that the mechanism of action of fluoride on caries control is local and the antimicrobial effect of fluoride may be marginal when compared with the physicochemical effect [52, 53].”
    Quote in the paperSubstantial claim0 of 2 sources checked
    • cites [52] JA Cury, 2008, How to maintain a cariostatic fluoride concentration in the oral environment, Adv Dent Res source
    • cites [53] LM Tenuta, 2010, Fluoride: its role in dentistry, Braz Oral Res source
    • Rests on an assumption: Fluoride interferes physicochemically with the caries process, reducing demineralization when pH falls after biofilm exposure to sugar and enhancing remineralization when pH rises above the critical.

  • It may state two separate claims as one.

    Premisecitation

    Fluoride may have antimicrobial effects but it is concentration-dependent.

    “Fluoride may have antimicrobial effects but it is concentration-dependent”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [51] DJ Bradshaw, 2002, Effects of glucose and fluoride on competition and metabolism within in vitro dental bacterial communities and biofilms, Caries Res source

  • Probably not a substantial claim.

    Premisecitation

    Some studies suggest that the anti-caries effect of fluoride on dentine is not of the same magnitude as that on enamel.

    “However, the knowledge about the anti-caries effect of fluoride on dentine is scarce [6, 16], and some studies suggest that it would not be of the same magnitude as that on enamel [17, 18].”
    Quote in the paperSubstantial claim0 of 2 sources checked
    • cites [17] JM ten Cate, 1999, Current concepts on the theories of the mechanism of action of fluoride, Acta Odontol Scand source
    • cites [18] FM Herkstroter, 1991, Demineralization of human dentine compared with enamel in a pH-cycling apparatus with a constant composition during de- and remineralization periods, Caries Res source

  • Probably not a substantial claim. The paper’s conclusions may not depend on it.

    Study design and conductreasoning

    The use of a single species biofilm could be considered a limitation.

    “Regarding methodological aspects, the use of a single specie biofilm could be considered a limitation.”
    Quote in the paperNot a substantial claim
    • Rests on an assumption: In dental biofilm there are hundreds of bacterial species and it is impossible to simulate this complexity in vitro.

  • It may state two separate claims as one.

    Study design and conductcitation

    The use of surface hardness as an indicator of dentine mineral loss has been widely employed because there is a high correlation with transversal microradiography, which directly quantifies demineralization in dental enamel and also in dentine.

    “About the use of surface hardness as indicator of dentine mineral loss, it has been widely employed [25, 33, 34, 36, 39, 56–59] because there is a high correlation with transversal microradiography [25], which directly quantifies demineralization in dental enamel and also in dentine [60].”
    Quote in the paperSubstantial claim0 of 10 sources checked
    • cites [25] GC Vale, 2011, APF and dentifrice effect on root dentin demineralization and biofilm, J Dent Res source
    • cites [33] YW Cavalcanti, 2014, A three-species biofilm model for the evaluation of enamel and dentin demineralization, Biofouling source
    • cites [34] RA Giacaman, 2014, Anticaries effect of an antioxidant-rich apple concentrate on enamel in an experimental biofilm-demineralization model, J Appl Microbiol source
    • cites [36] C Munoz-Sandoval, 2012, Effect of bovine milk on Streptococcus mutans biofilm cariogenic properties and enamel and dentin demineralization, Pediatr Dent
    • cites [39] AT Hara, 2003, Caries progression and inhibition in human and bovine root dentine in situ, Caries Res source
    • cites [56] CP Aires, 2002, Effect of a lactose-containing sweetener on root dentine demineralization in situ, Caries Res source
    • cites [57] SC Kusano, 2011, Timing of fluoride toothpaste use and enamel-dentin demineralization, Braz Oral Res source
    • cites [58] CP Aires, 2008, Effect of starch and sucrose on dental biofilm formation and on root dentine demineralization, Caries Res source
    • cites [59] AT Hara, 2004, Influence of the mineral content and morphological pattern of artificial root caries lesion on composite resin bond strength, Eur J Oral Sci source
    • cites [60] RZ Thomas, 2006, Transversal wavelength-independent microradiography, a method for monitoring caries lesions over time, validated with transversal microradiography, Caries Res source

  • Probably not a substantial claim. It may state two separate claims as one.

    Study design and conductnone given

    Biofilm weight and acidogenicity are not direct measures of microbial viability.

    “even when these are not at direct measured of microbial viability.”
    Quote in the paperSubstantial claim

  • It may state two separate claims as one.

    Interpretationreasoning

    The findings support the clinical data, suggesting that higher fluoride concentrations are necessary to control caries of root dentine than of enamel.

    “Furthermore, the findings support the clinical data, suggesting that higher fluoride concentrations are necessary to control caries of root dentine than of enamel.”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim. The paper’s conclusions may not depend on it.

    Premisecitation

    The present data extend those found by ten Cate et al. (1995), who showed that carious dentine incorporates more fluoride than enamel when treated with fluoride toothpaste and subjected to a chemical pH-cycling model.

    “The present data extend those found by ten Cate et al. (1995), who showed that carious dentine incorporates more fluoride than enamel when treated with fluoride toothpaste and subjected to a chemical pH-cycling model.”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites ten Cate et al. (1995) source

  • It may state two separate claims as one.

    Premisecitation

    Dentine has more amorphous calcium phosphate minerals than enamel, and fluoride activates the phase transformation of these minerals into fluorapatite.

    “Second, dentine has more amorphous calcium phosphate minerals than enamel and fluoride activates the phase transformation of these minerals in fluorapatite [9, 50].”
    Quote in the paperNot a substantial claim0 of 2 sources checked
    • cites [9] JS Wefel, 1994, Root caries histopathology and chemistry, Am J Dent
    • cites [50] EC Moreno, 1974, Chemistry of enamel subsurface demineralization in vitro, J Dent Res source

  • Probably not a substantial claim. The paper’s conclusions may not depend on it.

    Study design and conductnone given

    Assumptions of homogeneity of variances and normal distribution of errors were checked for all response variables tested.

    “Assumptions of homogeneity of variances and normal distribution of errors were checked for all response variables tested, and variables that did not satisfy these assumptions were transformed as suggested by the software.”
    Quote in the paperNot a substantial claim

  • It may state two separate claims as one.

    Premisecitation

    This model was successfully used to evaluate the effect of iron on enamel and dietary products on either enamel or dentine demineralization.

    “This model was successfully used to evaluate the effect of iron on enamel [37] and dietary products on either enamel or dentine demineralization [34–36].”
    Quote in the paperSubstantial claim0 of 4 sources checked
    • cites [37] CC Ribeiro, 2012, The effect of iron on Streptococcus mutans biofilm and on enamel demineralization, Braz Oral Res source
    • cites [34] RA Giacaman, 2014, Anticaries effect of an antioxidant-rich apple concentrate on enamel in an experimental biofilm-demineralization model, J Appl Microbiol source
    • cites [35] RA Giacaman, 2012, Effect of fluoridated milk on enamel and root dentin demineralization evaluated by a biofilm caries model, Caries Res source
    • cites [36] C Munoz-Sandoval, 2012, Effect of bovine milk on Streptococcus mutans biofilm cariogenic properties and enamel and dentin demineralization, Pediatr Dent

  • Probably not a substantial claim.

    Premisecitation

    For dentine, higher fluoride concentration is necessary to control caries.

    “For dentine, higher fluoride concentration [19–23], higher frequency of use [24], or combination of methods of fluoride delivery [25] should be necessary to control caries; however, the evidence is not conclusive.”
    Quote in the paperSubstantial claim0 of 5 sources checked
    • cites [19] A Baysan, 2001, Reversal of primary root caries using dentifrices containing 5,000 and 1,100 ppm fluoride, Caries Res source
    • cites [20] JM ten Cate, 1995, pH-cycling of enamel and dentin lesions in the presence of low concentrations of fluoride, Eur J Oral Sci source
    • cites [21] M Srinivasan, 2014, High-fluoride toothpaste: a multicenter randomized controlled trial in adults, Community Dent Oral Epidemiol source
    • cites [22] KR Ekstrand, 2013, A randomized clinical trial of the anti-caries efficacy of 5,000 compared to 1,450 ppm fluoridated toothpaste on root caries lesions in elderly disabled nursing home residents, Caries Res source
    • cites [23] CA Yeung, 2014, Some beneficial effect on root caries from use of higher concentration fluoride toothpaste (5000 ppm F), Evid Based Dent source

  • It may state two separate claims as one.

    Premisecitation

    We improved a S. mutans biofilm model, which was validated to evaluate the effect of antibacterial substances on biofilm formation and enamel demineralization, named cariogenic biofilm model given the cariogenic properties of this bacterium.

    “For this purpose, we improved a S. mutans biofilm model [32], which was validated to evaluate the effect of antibacterial substances on biofilm formation [28] and enamel demineralization [37], named cariogenic biofilm model [36] given the cariogenic properties of this bacterium.”
    Quote in the paperSubstantial claim0 of 3 sources checked
    • cites [32] H Koo, 2003, Inhibition of Streptococcus mutans biofilm accumulation and polysaccharide production by apigenin and tt-farnesol, J Antimicrob Chemother source
    • cites [28] RA Ccahuana-Vásquez, 2010, S. mutans biofilm model to evaluate antimicrobial substances and enamel demineralization, Braz Oral Res source
    • cites [37] CC Ribeiro, 2012, The effect of iron on Streptococcus mutans biofilm and on enamel demineralization, Braz Oral Res source

  • Probably not a substantial claim.

    Interpretationreasoning

    Assuming the effect of fluoride on dentine was equivalent to that on enamel, dentine would have to be treated with fluoride concentration 3× higher than enamel (1,350 vs. 450 ppm F).

    “Thus, assuming the effect of fluoride on dentine was equivalent to that on enamel, dentine would have be treated with fluoride concentration 3× higher than enamel, 1,350 vs. 450 ppm F, as shown in Table 2.”
    Quote in the paperSubstantial claim
    • The authors state this as an assumption: The effect of fluoride on dentine is equivalent to that on enamel.

  • Probably not a substantial claim. The paper’s conclusions may not depend on it.

    Premisecitation

    For dentine, higher frequency of fluoride use is necessary to control caries.

    “For dentine, higher fluoride concentration [19–23], higher frequency of use [24], or combination of methods of fluoride delivery [25] should be necessary to control caries; however, the evidence is not conclusive.”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [24] AM Laheij, 2010, In situ remineralisation of enamel and dentin after the use of an amine fluoride mouthrinse in addition to twice daily brushings with amine fluoride toothpaste, Caries Res source
33 of 33

  • The authors state this as an assumption.

    The effect of fluoride on dentine is equivalent to that on enamel.

    “assuming the effect of fluoride on dentine was equivalent to that on enamel”

  • The paper relies on this without support.

    Ca is a chemical indicator of enamel and dentine demineralization.

    “Ca is a chemical indicator of enamel and dentine demineralization”

  • The paper relies on this without support.

    Fluoride interferes physicochemically with the caries process, reducing demineralization when pH falls after biofilm exposure to sugar and enhancing remineralization when pH rises above the critical.

    “Fluoride interferes physicochemically with the caries process, reducing the demineralization of enamel and dentine when the pH falls after biofilm exposure to sugar and enhancing the remineralization process when pH rises again above the critical.”

  • The paper relies on this without support.

    In dental biofilm there are hundreds of bacterial species and it is impossible to simulate this complexity in vitro.

    “in dental biofilm there are hundreds of bacterial species and it is impossible to simulate this complexity in vitro.”

  • The paper relies on this without support.

    This cariogenic biofilm model has not been validated in terms of dose-response to evaluate the effect of fluoride on either enamel or dentine.

    “However, this cariogenic biofilm model has not been validated in terms of dose-response to evaluate the effect of fluoride on either enamel or dentine, justifying the present publication.”
5 of 5

Self-check

Percentages, sums and reported differences re-computed from the paper’s own numbers.

  • Toothpaste and treatment concentrations do not share the stated dilution

    Minor

    The stated 1:3 dilution does not map 1,100 ppm F toothpaste to a 450 ppm F treatment: 1,100 ÷ 450 is about 2.44, not 3. The other listed concentration pairs also imply different dilution factors.

    Reported 3 · recomputed 2.444444

1 of 1

Citations

Cites

Flagged first, then by citations

Research works printed but not linked: 1

  1. HM Negri, 2002, Dose-response effect of a dentifrice formulation with low fluoride concentration—an in vitro study, Pesqui Odontol Bras, 16, 361

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Metadata

Authors
Fernández, C. E., Tenuta, L. M. A., & Cury, J. A.
Affiliations
Universidade Estadual de Campinas (UNICAMP) (BR)
Corresponding author
Cury, Jaime A.
ORCID
Venue
PLOS ONE
Publisher
Public Library of Science (PLoS)
Published
2016-01-05
Volume
11
Issue
1
Pages
e0146478
ISSN
1932-6203 (ISSN-L)
DOI
10.1371/journal.pone.0146478
PMC
PMC4712139
OpenAlex
W2225260200
Semantic Scholar
e2415bf625628606a16e38128166e2d796495176
Cited by
74
References
61
Citations by year
2026: 3 · 2025: 5 · 2024: 8 · 2023: 4 · 2022: 8 · 2021: 12 · 2020: 8 · 2019: 6 · 2018: 6 · 2017: 8 · 2016: 5
FWCI
10.83
Type
journal article
Language
en
Open access
Licence
Locations
  • PLoS ONE (publishedVersion, cc-by)
  • PubMed Central (publishedVersion, cc-by)
  • PubMed (publishedVersion)
  • LA Referencia (Red Federada de Repositorios Institucionales de Publicaciones Científicas) (publishedVersion, other-oa)
  • Americanae (AECID Library) (submittedVersion, other-oa)
  • DOAJ (DOAJ: Directory of Open Access Journals) (submittedVersion, cc-by-sa)
Funders
  • International Association for Dental Research
  • Universidade Estadual de Campinas
  • Comisión Nacional de Investigación Científica y Tecnológica
Topics
  • Health Sciences › Dentistry › General Dentistry › Dental Health and Care Utilization
  • Health Sciences › Dentistry › Periodontics › Oral microbiology and periodontitis research
  • Health Sciences › Dentistry › General Dentistry › Dental Erosion and Treatment
Keywords
fluoride, root caries, enamel demineralization, Streptococcus mutans, fluoride uptake, gingival recession, dose-response relationship
MeSH terms
Animals, Cattle, Dental Caries, Dental Enamel, Dentin, Models, Biological, Sodium Fluoride, Streptococcus mutans, Tooth, Tooth Demineralization, Biofilms

About these checks

Registry, retraction, Cites and statistics results are computed, not judged, with one exception: a printed reference that no index lists is read once by a model before it counts as a citation error. Claims are extracted by a model and kept only when their quote appears verbatim in the text; each cited source is then checked, with a model’s help, for whether it says what the claim relies on. Those verdicts can be wrong — read the claim’s quote and the cited source before relying on one.

A language model drew the claims from the paper on 2026-11-10, under version 3 of the claim definition (model deepseek-v4.1-flash, prompt extract-v3).

A second model labelled each claim on 2026-11-10 (model jev-1.13-20260917, definition revision gold-guideline-v0.2).

Statistics and arithmetic are recomputed, not judged.

Confidence bands are shown only for fields calibrated on our annotated test set. None is calibrated yet, so no band is shown.

What counts as a claim ›How we measure confidence ›How we check this ›

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