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Brazilian Oral Research

 ISSN 1806-8324 ISSN 1807-3107

        01--2019

http://dx.doi.org/10.1590/1807-3107bor-2019.vol33.0051 

Original Research

Pediatric Dentistry

Fluoride content in children’s dentifrices marketed in Lima, Peru

Bertha Angélica CHÁVEZ(a) 
http://orcid.org/0000-0002-6057-6162

Gissela Briceño VERGEL(a) 
http://orcid.org/0000-0003-2119-7044

Carol Ponce CÁCERES(a) 
http://orcid.org/0000-0002-2641-7133

Matheus França PERAZZO(b) 
http://orcid.org/0000-0003-1231-689X

Raquel Gonçalves VIEIRA-ANDRADE(b) 
http://orcid.org/0000-0003-0284-7216

Jaime Aparecido CURY(c) 
http://orcid.org/0000-0003-1046-5605

(a)Maternal Perinatal Institute, Lima, Peru.

(b)Universidade Federal de Minas Gerais – UFMG, Department of Pediatric Dentistry and Orthodontics, Belo Horizonte, MG, Brazil.

(c)Universidade Estadual de Campinas – Unicamp, Piracicaba Dental School, Piracicaba, SP, Brazil.

Abstract

The aim of the present study was to determine the concentration of total fluoride (TF) and total soluble fluoride (TSF) in children’s dentifrices marketed in the city of Lima, Peru. Three samples of 23 dentifrices (4 without fluoride and 19 with fluoride) were purchased in different pharmacies in Lima, Peru. The TF and TSF concentrations found in the dentifrices were determined by ion-selective electrode, expressed in ppm F (μg F/g of dentifrice). The TF concentration in the majority of the fluoride toothpastes matched that shown on the label, except for one declared as 1450 ppm F by the manufacturer, whereas only 515.1 ppm F was found. The concentration of TSF found in the fluoride toothpastes ranged from 457.5 to 1134.8 ppm F. All the dentifrices were formulated with silica, but one also presented calcium carbonate. In conclusion, 83% of the children’s dentifrices marketed in Lima, Peru, were fluoridated, but only 53% contained a TSF concentration greater than 1000 ppm F, the minimum concentration required to provide an anticaries effect.

Key words: Fluorides; Pediatric Dentistry; Toothpastes

Introduction

The use of toothpaste with fluoride has been recommended for over 50 years to prevent and control dental caries.1 Topical fluoride is considered one of the most effective public healthcare strategies to control caries, especially among the child population, which is the most vulnerable.2 The anticaries effect of fluoride toothpastes, together with the correct toothbrushing technique, promotes the disruption of biofilm, and maintains the demineralization-remineralization balance.3 An amount of 1000 ppm of F in toothpaste achieves this benefit, but the F must be in soluble form (SF) for it to be active in its formulation, and thus be able to interfere in the development of a disease.1,4,5,6,7,8

The presence of SF in a dentifrice depends on its formulation, in terms of type of fluoride salt and abrasive used. The dentifrices that contain sodium fluoride (NaF) have high fluoride availability, because they are formulated with silica as an abrasive agent. When the toothpaste is formulated with an abrasive containing calcium (calcium carbonate or dicalcium phosphate dihydrate), it must contain sodium monofluorophosphate (MFP) as a fluoridating agent, because the MFP ion does not react immediately with Ca++.6,9 However, this type of formulation is not totally stable, and the F concentration decreases by 40% one year after manufacture. For this reason, it is better not to purchase a product, if it does not show an expiration date.6,10,11

The recommendations for fluoride toothpaste use in infants and children have been modified in recent years in an effort to maximize caries prevention, and minimize the risk of dental fluorosis1. Some healthcare professionals put off using of fluoridated dentifrice in children; this is an inappropriate approach, since there is no scientific evidence to conclude that the use of fluoridated dentifrices in children under 12 months of age is associated with fluorosis.2,12 On the other hand, recommending dentifrices without F or with a low F concentration to avoid fluorosis is irresponsible, since the at-home application of F through toothpaste is the best public healthcare strategy to prevent and control caries.13,14 Scientific evidence indicates that fluoridated toothpaste should be used as soon as the first tooth appears in the oral cavity.13 Therefore, it is up to pediatric health professionals to make recommendations regarding toothpaste expiration dates and minimum amount of F for an anticaries effect, especially in areas where fluoridated drinking water is not available.15,16

The regulations made by some countries, such as the US and Mercosur member countries, do not require companies to state the amount of SF in a given product.2 Peru is subject to Sanitary Technical Standard 2001 regulating the addition of fluorides to toothpastes, approved by M.R. No. 454-2001-SA/DM, which states merely that toothpastes for children must have an SF concentration of less than 600 ppm one year after being manufactured, and 450 ppm until their expiration.17 The last Peruvian study that evaluated the concentration and stability of fluoride was published in the mid-twentieth century.18

Considering the importance of the SF concentration in toothpastes, it was decided to evaluate this concentration in children’s dentifrices marketed in the city of Lima, Peru, and to compare it with the information declared by the manufacturer on the packaging label, in order to substantiate information that guarantees the anticaries effect of dentifrices.

Methodology

Twenty-three dentifrices marketed for children’s use and found in different pharmacy chains in the city of Lima, Peru, during the period from June to July 2017, were purchased in triplicate of different batches (total = 69). The samples were coded to allow blind analysis. The manufacturer’s information about the dentifrices are described in Table 1.

Table 1 Information regarding the dentifrices analyzed (Lima, Peru). 

Sample Name Fluoride declared on packaging (ppm) Active ingredient Abrasive specified on packaging Manufacture date Expiration date Country of manufacture
A Denture BB Without fluoride Lacking Silica, hydrated silica Jul 16 Jul 19 Ecuador
B Dentito Baby Without fluoride Lacking Silica Apr 17 Aug 19 Peru
C Aquafresh Baby teeth Without fluoride Lacking Silica Not specified Apr 18 USA
D Colgate My First Without fluoride Lacking Hydrated silica Not specified Oct 17 USA
E Farma Dent Kids 452 NaF Silica Not specified Jul 21 China
F Colgate Smiles (Sponge Bob, Barbie) 500 NaF Hydrated silica Not specified Jan 20 Mexico
G Denture Kids Not specified MFP Silica Aug 16 Aug 19 Ecuador
H Aquafresh Little Teeth 500 NaF Hydrated silica Not specified Jan 18 USA
I Oral B Stages (Frozen, Star Wars, Princesses, Mickey Mouse) 500 NaF Hydrated silica Oct 16 Sep 18 Mexico
J Dentito gum flavor 550 MFP Silica Not specified May 20 Peru
K Dentito Chicha Morada flavor 550 MFP Silica Not specified Mar 20 Peru
L Tuinies Hello Kitty 580 NaF Hydrated silica Not specified Jul 20 China
M Tuinies Peppa Pig 1450 NaF Hydrated silica Not specified Jun 21 China
N Oral B 123 1000 NaF Hydrated silica Not specified Jun 18 Mexico
O Dento Junior watermelon flavor 1100 NaF Silica Not specified Oct 19 Peru
P Colgate Kids strawberry flavor 1100 NaF Hydrated silica Not specified Feb 20 Brazil
Q Ipana Hydrated silica Not specified Feb 20 Peru
1100 NaF
R Colgate Kids grape flavor 1100 NaF Hydrated silica Not specified Feb 20 Brazil
S Colgate Smiles (Barbie, Minions, Spiderman) 1100 NaF Hydrated silica Not specified Feb 20 Mexico
T Colgate Kids tutti-frutti flavor 1100 NaF Hydrated silica Not specified Feb 20 Brazil
U Tuinies Hello Kitty-Xtreme White 1450 NaF Hydrated silica Not specified July 20 China
MFP
V Vitis Junior 1000 NaF Silica Not specified Dec 19 Spain
W Aquafresh “My Big Teeth” 1150 NaF Hydrated silica Not specified Feb 19 USA

NaF: Sodium fluoride; MFP: Sodium monofluorophosphate (MFP = Na2FPO3).

In regard to chemical analysis, total soluble fluoride (TSF or free F) concentrations were determined, including F ion (FI) and fluoride as sodium monofluorophosphate (MFP), and total fluoride (TF), corresponding to the sum of TSF and insoluble F (IF), which may be bound to the abrasive. Ninety to 110 mg of each dentifrice (± 0.01 mg) were weighed and homogenized vigorously in 10.0 ml of deionized water. An aliquot of 0.25 ml of the suspension was transferred from each toothpaste tube (total = 69) to TF-labeled test tubes, and 0.25 ml of 2 M HCl was added. The tubes were heated to 45°C and kept at this temperature for 1 hour to hydrolyze the MFP ion to the F ion, and to dissolve the IF bound to the abrasive.

The resulting acid suspension was neutralized with 0.5 ml of 1 M NaOH, and buffered with 1 ml of TISAB II (1 M acetate buffer, pH 5.0, containing 1 M NaCl and 0.4% CDTA). The suspension was centrifuged for 10 min to 3000 g at room temperature to remove the IF, and the supernatant was used to determine TSF and IF. Afterwards, 0.25 ml of the supernatant was transferred to tubes labeled as TSF, and treated as described for TF. The F concentrations in the tubes (TF and TSF) were evaluated using an F electrode (Thermo Scientific Orion 96-09, Orion Research, Cambridge, MA, USA), coupled to an ion analyzer (Star A214, Thermo Scientific Orion). The electrode was calibrated with standard F solutions from 0.06 to 8.0 µg F/mL, prepared in 0.25 M NaOH, 0.25 M HCl and TISAB II 50% (v/v). A linear regression between the logarithm of F concentrations in standard and respective mV values was determined using Excel software (Microsoft, Redmond, USA). The mathematical regression equation was used to calculate the concentration of F in dentifrice (Figure 1). Using the determined amounts of TF and TSF, the IF concentration was calculated as TF – TSF, and the percentage of IF was obtained by dividing the IF concentration by TF, and multiplying by 100. The analysis of each tube of toothpaste was carried out in triplicate.

Figure 1 Calibration curve (n = 4) and data on the correlation between the logarithm of fluoride concentrations in the standard and relative mV values generated 

The data were reported by the biochemistry laboratory of the School of Dentistry, University of Piracicaba (Unicamp), Brazil, and were processed according to an automated tabulation method, after which an analysis of frequency was performed according to the objectives specified.

Results

The 23 dentifrices analyzed in this study included four dentifrices without F, one with an unspecified concentration of F, and 18 with F concentrations from 452 to 1450 ppm. The main active ingredients used were NaF, present in 15 of the analyzed samples, and MFP, present in three; one sample contained both active ingredients (NaF and MFP) (Table 1). In relation to the abrasives reported on the packaging, the most common were silica and hydrated silica. The abrasive agents declared by the manufacturer matched those found, except for Sample U (Tuinies Hello Kitty Extreme White), whose packaging indicated silica, but whose analysis revealed calcium carbonate. The expiration date was informed on all the products; however, the manufacture date was reported on just four.

The TF concentration declared on the packaging of 21 of the 23 dentifrices analyzed in this study was close to the value found (Table 2 and Figure 2). Only Denture Kids toothpaste (Sample G) did not declare any F content on the packaging, but the analysis found an amount of 476.4 (± 2.8) ppm of F in its composition. In addition, Tuinies Peppa Pig toothpaste (Sample M) declared a concentration of 1450 ppm of F in its composition, whereas the laboratory analysis revealed a concentration of only 515.1 (± 10.5) ppm of F.

Table 2 As declared on label: total fluoride (TF) and total soluble fluoride (TSF) concentration (mg F/kg) found, and % of insoluble fluoride (IF) in the dentifrices analyzed (average ± sd; n = 3). 

Sample Dentifrice Expected TF (ppm) TF found TSF found IF (%)
A Denture BB Without fluoride 0.0 ± 0.0 0.0 ± 0.0 na
B Dentito Baby Without fluoride 0.0 ± 0.0 0.0 ± 0.0 na
C Aquafresh Baby Teeth Without fluoride 0.0 ± 0.0 0.0 ± 0.0 na
D Colgate My First Without fluoride 0.0 ± 0.0 0.0 ± 0.0 na
E Farma Dent Kids 452 428.3 ± 1.5 457.5 ± 10.5 0.0
F Colgate Smiles (Sponge Bob, Barbie) 500 472.3 ± 7.7 489.6 ± 2.0 0.0
G Denture Kids Not specified 476.4 ± 2.8 492.1 ± 5.7 0.0
H Aquafresh Little Teeth 500 477.3 ± 29.3 481.8 ± 13.2 0.0
I Oral B Stages (Frozen, Star Wars, Princesses, Mickey Mouse) 500 479.1 ± 5.6 499.1 ± 6.5 0.0
J Dentito gum flavor 550 510.0 ± 9.3 551.7 ± 9.8 0.0
K Dentito Chicha Morada flavor 550 512,6 ± 8.2 550.6 ± 15.6 0.0
L Tuinies Hello Kitty 580 514.7 ± 19.4 541.4 ± 20.6 0.0
M Tuinies Peppa Pig 1450 515.1 ± 10.5 531.0 ± 8.6 0.0
N Oral B 1-2-3 1000 1017.2 ± 8.6 1055.0 ± 7.6 0.0
O Dento Junior watermelon flavor 1100 1022.8 ± 46.5 1063.7 ± 35.7 0.0
P Colgate Kids strawberry flavor 1100 1055.5 ± 58.1 1134.8 ± 52.1 0.0
Q Ipana 1100 1056.5 ± 21.1 1104.1 ± 16.5 0.0
R Colgate Kids Grape 1100 1058.5 ± 21.1 1081.7 ± 9.0 0.0
S Colgate Smiles (Barbie, Minions, Spiderman) 1100 1065.7 ± 15.4 1093.9 ± 5.6 0.0
T Colgate Kids tutti-frutti flavor 1100 1085.9 ± 16.8 1127.9 ± 13.9 0.0
U Tuinies Hello Kitty - Xtreme White 1450 1307.6 ± 22.3 1061.4 ± 56.1 18.8
V Vitis Junior 1000 982.4 ± 18.6 1001.1 ± 4.9 0.0
W W Aquafresh “My Big Teeth” 1150 1069.1 ± 6.7 1112.2 ± 13.1 0.0

TF: Total fluoride; TSF: Total soluble fluoride; IF: Insoluble fluoride.

*Diference between TF found and expected of analytical signivicance (± 5%).

Figure 2 Concentration (ppm F) of total fluoride declared by the manufacturer (TF expected) and found in the toothpastes analyzed (TF found) 

Furthermore, we found that the average concentration of TF was slightly lower than the concentration of TSF in 18 of the 19 fluoridated dentifrices analyzed. Only the Tuinies Hello Kitty - Xtreme White sample (Sample U) showed a concentration of TF (1,307.6 ± 22.3) greater than TSF (1,061.4 ± 56.1). Almost 20% of the TF of this formulation is insoluble (Table 2). Although the label indicates that the abrasive is silica, we checked and were surprised to find that the abrasive was calcium carbonate, not silica. In regard to the dentifrices claiming they did not contain F (17% of the total dentifrices analyzed), the information declared is similar to what was actually found. Of the 23 dentifrices analyzed, 53% (n = 13) showed that a minimum concentration of F had a high anticaries potential (Table 3 and Figure 3).

Table 3 Concentration of total soluble fluoride (average ±sd; n=3) in the dentifrices analyzed, and their anticaries potentials. 

Sample Dentifrice Average TSF found (± sd) Anticaries potential
A Denture BB 0.0 ± 0.0 None
B Dentito Baby 0.0 ± 0.0 None
C Aquafresh Baby Teeth 0.0 ± 0.0 None
D Colgate My First 0.0 ± 0.0 None
E Farma Dent Kids 457.5 ± 10.5 Low
F Colgate Smiles (Sponge Bob, Barbie) 489.6 ± 2.0 Low
G Denture Kids 492.1 ± 5.7 Low
H Aquafresh Little Teeth 481.8 ± 13.2 Low
I Oral B Stages (Frozen, Star Wars, Princesses, Mickey Mouse) 499.1 ± 6.5 Low
J Dentito gum flavor 551.7 ± 9.8 Low
K Dentito Chicha Morada flavor 550.6 ± 15.6 Low
L Tuinies Hello Kitty 541.4 ± 20.6 Low
M Tuinies Peppa Pig 531.0 ± 8.6 Low
N Oral B 1-2-3 1055.0 ± 7.6 High
O Dento Junior watermelon flavor 1063.7 ± 35.7 High
P Colgate Kids strawberry flavor 1134.8 ± 52.1 High
Q Ipana 1104.1 ± 16.5 High
R Colgate Kids Grape 1081.7 ± 9.0 High
S Colgate Smiles (Barbie, Minions, Spiderman) 1093.9 ± 5.6 High
T Colgate Kids tutti-frutti flavor 1127.9 ± 13.9 High
U Hello Kitty - Xtreme White 1061.4 ± 56.1 High
V Vitis Junior 1001.1 ± 4.9 High
W W Aquafresh “My Big Teeth” 1112.2 ± 13.1 High

TSF: Total soluble fluoride.

Figure 3 Concentration (ppm F) of total fluoride (TF found) and total soluble fluoride found (TSF found) in the toothpastes analyzed. 

Discussion

The therapeutic efficacy of a toothpaste is based on the release of fluoride into the oral environment at the time of brushing; for this reason, its formula must provide SF.19-21 In our study, only 53% of the samples had the minimum concentration needed to promote an anticaries effect (1,000 ppm).

Sample G (Denture Kids) does not state the concentration of F on the packaging, and the analysis showed 492.1 ppm of F, whereas Sample M (Tuinies Peppa Pig) states 1,400 ppm F, with the analysis showing only 38% of the value declared (531 ppm F). A discordant value was also found in the study by Giacaman et al.16 (Chile), who found a dentifrice whose amount of F declared by the manufacturer was 450 ppm, whereas the amount of F found exceeded this amount threefold.

These discordant values between the F declared by the manufacturer on the packaging and the F analyzed are seriously prejudicial to consumers, since this misinformation violates their right to truthful information. It is troublesome that the products do not reflect the real value. In 17 (73.9%) dentifrices analyzed, the TF declared by the manufacturer on the label was lower than that found. This percentage contrasts with that of Cury et al.2 and Loureiro et al.,22 who found a respective 84.4% and 83.3% similarity between the F declared and the F found in Brazilian dentifrices. Nevertheless, the similarity in values found by Carrera et al.23 was 77.2% between the F declared and the F found. On the other hand, in a study24 with 22 fluoride toothpastes commercially available in South Africa, the TF concentration of all the toothpastes was lower than that declared by the manufacturers, with one in four having TSF concentrations of less than 1,000 ppm F.

As for the active ingredients used, the type of F declared on the dentifrices coincides 100% with that found in the analysis. In silica-based preparations of 1000 ppm of F, NaF constitutes 0.22% of the dentifrice and is highly ionizable; therefore, it becomes active as soon as it enters the mouth, stimulating the remineralization of decalcified enamel and interfering in the growth and development of bacteria in dental plaque.20 NaF was present in 70% of the samples analyzed (E, F, H, I, L, M, N, O, P, Q, R, S, T, V, W), and MFP, in 30% of the samples (G, J, K). These results agree with those of Loureiro’s study22 in Uruguay, in which most of the dentifrices that he evaluated were found to use NaF. A previous study25 developed with toothpastes on the Belgian market, using a specific method to determine the amount of NaF, sodium monofluorophosphate (SMFP) and amine fluoride (AmF), also found all the samples analyzed to be in conformity with the local guidelines. However, the maximum total fluoride concentration allowed by European guidelines is 0.15 % (1,500 ppm F).

Regarding the active ingredient used, only Sample U (Tuinies Hello Kitty - Xtreme White) uses two types of F (MFP and NaF), similar to the findings of the study by Benzian26 in Brunei, Cambodia, Laos, the Netherlands and Suriname, in which two dentifrices were found to combine MFP and NaF. Most silica-based toothpastes contain highly ionizable NaF, which is activated as soon as it comes into contact with the tooth surface. If NaF is combined with a calcium carbonate-based abrasive agent, it binds to the calcium of the abrasive agent, forming calcium fluoride (CaF2) inside the toothpaste tube and not on the tooth surface. In this case, the CaF2 formed in the toothpaste does not release F, thus inhibiting its preventive action.

Abrasives can include silica, hydrated silica and calcium carbonate (or dicalcium phosphate dihydrate). It is important to note that dentifrices containing calcium carbonate or dicalcium phosphate dihydrate as an abrasive must be formulated with MFP, whereas NaF-based ones must have silica (hydrated silica) as their abrasive agent. In this study, the abrasive appearing on the packaging was mostly hydrated silica: 61%, followed by silica: 35%, and both: 4%. According to the label, toothpaste U (Tuinies Hello Kitty - Xtreme White) was formulated adequately with a NaF/MFP silica-based abrasive, but we found that the abrasive was actually calcium carbonate. This is explainable, because we found 20% of IF in this formulation. A study developed with toothpastes marketed in India27 also found that the mean percentage of TSF concentration in SMFP/CaCO3- (calcium carbonate) based toothpastes was 86% (SD = 16%), whereas that in NaF/Si- (silica) based toothpastes was 98% SD 1%, and that in the remaining toothpastes with unknown abrasive was 95% SD 1%.

The present study provides results that can contribute to modifying the current guidelines that regulate the concentration of children’s toothpaste marketed in Peru. The last national caries survey found a prevalence of dental caries in deciduous, mixed and permanent dentitions of 59.1%, 85.5% and 57.6%, respectively.28 Pertinent changes in the Peruvian regulations on adequate F concentration could guarantee the use of toothpastes that effectively control dental caries.29,30 Accordingly, it could reduce the polarization of dental caries according to socioeconomic status, since children from low-income families usually have more dental caries than those with a higher income.30 In addition, the prevention of oral conditions can minimize social, functional, economic and behavioral impacts on children and/or parents.29,30,31

The present results are an alert for other regions of the world having resolutions that lack guidelines on the beneficial anticaries effect of fluoride, as in Mercosur countries.32 Knowing the benefit of toothpastes with adequate concentrations of fluoride allows effective strategies to be established to control caries. In addition, the present study shows that the Peruvian health surveillance system fails to control imported dentifrices from China, corroborating a previous analysis on the dentifrice market in Chile.16

Conclusion

Most of the children’s dentifrices marketed in Lima, Peru, at the time of this study, were fluoridated, but only 53% contained a TSF concentration greater than 1000 ppm F, the minimum concentration needed to provide an anticaries effect. Therefore, the concentrations of F in toothpastes for children in Lima seem inappropriate for dental caries control, and must be rectified in public health policies.

Acknowledgements

We are grateful to Mr. Waldomiro Vieira Filho, from the Oral Biochemistry Laboratory, FOP-UNICAMP, for his technical analysis. This study was supported by the Federal University of Minas Gerais (UFMG) and financed in part by the Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - Brasil (CAPES) - Finance Code 001.

References

1. Wright JT, Hanson N, Ristic H, Whall CW, Estrich CG, Zentz RR. Fluoride toothpaste efficacy and safety in children younger than 6 years: a systematic review. J Am Dent Assoc. 2014 Feb;145(2):182-9. https://doi.org/10.14219/jada.2013.37Links ]

2. Cury JA, Oliveira MJ, Martins CC, Tenuta LM, Paiva SM. Available fluoride in toothpastes used by Brazilian children. Braz Dent J. 2010;21(5):396-400. https://doi.org/10.1590/S0103-64402010000500003Links ]

3. Noronha MS, Romão DA, Cury JA, Tabchoury CP. Effect of fluoride concentration on reduction of enamel demineralization according to the cariogenic challenge. Braz Dent J. 2016 Jul-Aug;27(4):393-8. https://doi.org/10.1590/0103-6440201600831Links ]

4. Santos AP, Oliveira BH, Nadanovsky P. Effects of low and standard fluoride toothpastes on caries and fluorosis: systematic review and meta-analysis. Caries Res. 2013;47(5):382-90. https://doi.org/10.1159/000348492Links ]

5. dos Santos AP, Nadanovsky P, Oliveira BH. A systematic review and meta-analysis of the effects of fluoride toothpastes on the prevention of dental caries in the primary dentition of preschool children. Community Dent Oral Epidemiol. 2013 Feb;41(1):1-12. https://doi.org/10.1111/j.1600-0528.2012.00708.xLinks ]

6. Cury JA, Dantas ED, Tenuta LM, Romão DA, Tabchoury CP, Nóbrega DF, et al. Fluoride concentration in most sold MFP/CaCO3 - based Brazilian toothpastes at the expiration time. Rev Assoc Paul Cir Dent. 2015 Jul/Sep;69(3):248-51. [ Links ]

7. Walsh T, Worthington HV, Glenny AM, Appelbe P, Marinho VC, Shi X. Fluoride toothpastes of different concentrations for preventing dental caries in children and adolescents. Cochrane Database Syst Rev. 2010 Jan;(1):CD007868. https://doi.org/10.1002/14651858.CD007868.pub2Links ]

8. Costa CM, Carlo F, Sampaio F, Forte F. fluoride concentration in commercial brands of dentifrices available in the state of Paraíba, Brazil. Pesq Bras Odontoped Clin Integr. 2013 Oct/Dec;13(4):323-7. https://doi.org/10.4034/PBOCI.2013.134.04Links ]

9. Yaghini J, Kiani S, Mortazavi S, Haghshenas B, Mogharehabed A. Assessment of available and stable fluoride in four widely-used toothpastes in the Iranian market. J Dent (Tehran). 2014 Sep;11(5):604-9. [ Links ]

10. Sebastian ST, Siddanna S. Total and Free Fluoride Concentration in Various Brands of Toothpaste Marketed in India. J Clin Diagn Res. 2015 Oct;9(10):ZC09-12. https://doi.org/10.7860/JCDR/2015/13382.6578Links ]

11. Veeresh DJ, Wadgave U. Assessment of total and soluble fluoride content in commercial dentifrices in Davangere: a cross sectional survey. J Indian Assoc Public Health Dent. 2014 Oct/Dec;12(4):320-2. https://doi.org/10.4103/2319-5932.147679Links ]

12. Tenuta LM, Cury JA. Fluoride: its role in dentistry. Braz Oral Res. 2010;24 Suppl 1:9-17. https://doi.org/10.1590/S1806-83242010000500003Links ]

13. Bergamo ET, Barbana M, Terada RS, Cury JA, Fujimaki M. Fluoride concentrations in the water of Maringá, Brazil, considering the benefit/risk balance of caries and fluorosis. Braz Oral Res. 2015;29(1):47. https://doi.org/10.1590/1807-3107BOR-2015.vol29.0047Links ]

14. Wennhall I, Matsson L, Schröder U, Twetman S. Outcome of an oral health outreach programme for preschool children in a low socioeconomic multicultural area. Int J Paediatr Dent. 2008 Mar;18(2):84-90. https://doi.org/10.1111/j.1365-263X.2007.00903.xLinks ]

15. Balaban R, Aguiar CM, da Silva Araújo AC, Dias Filho EB. Knowledge of paediatricians regarding child oral health. Int J Paediatr Dent. 2012 Jul;22(4):286-91. https://doi.org/10.1111/j.1365-263X.2011.01196.xLinks ]

16. Giacaman RA, Carrera CA, Muñoz-Sandoval C, Fernandez C, Cury JA. Fluoride content in toothpastes commercialized for children in Chile and discussion on professional recommendations of use. Int J Paediatr Dent. 2013 Mar;23(2):77-83. https://doi.org/10.1111/j.1365-263X.2012.01226.xLinks ]

17. Ministerio de Salud (Perú). Resolución ministerial 154-2001- SA/DM. Chile: Ministerio de Salud; 2001. [ Links ]

18. Sarmiento RV, Issáo M, Cury JA. A study on the availability and stability of fluoride dentifrices commercialized in Peru. Rev Estomatol Hered. 1994;4(1/2):12-20. [ Links ]

19. Oliveira MJ, Martins CC, Paiva SM, Tenuta LM, Cury JA. Estimated fluoride doses from toothpastes should be based on total soluble fluoride. Int J Environ Res Public Health. 2013 Nov;10(11):5726-36. https://doi.org/10.3390/ijerph10115726Links ]

20. Rosales JC, Cardoso DC, Chaires IC, Mejía MA. Dentífricos fluorados: composición. Vertientes Rev Especializada Cienc Salud. 2014;17(2):114-9. [ Links ]

21. Fernández CE, Carrera CA, Muñoz-Sandoval C, Cury JA, Giacaman RA. Stability of chemically available fluoride in Chilean toothpastes. Int J Paediatr Dent. 2017 Nov;27(6):496-505. https://doi.org/10.1111/ipd.12288Links ]

22. Loureiro LA, Fager AF, Santos Moreira MJ, Maltz M, Hashizume LN. Fluoride availability and stability in children’s toothpastes in Uruguay. J Dent Child (Chic). 2017 May;84(2):52-7. [ Links ]

23. Carrera CA, Giacaman RA, Muñoz-Sandoval C, Cury JA. Total and soluble fluoride content in commercial dentifrices in Chile. Acta Odontol Scand. 2012 Dec;70(6):583-8. https://doi.org/10.3109/00016357.2011.640287Links ]

24. Vorster L, Naidoo S, Stauf N, Holmgren C, Benzian H. Fluoride content of toothpastes available in South Africa. Community Dent Health. 2018 Aug;35(3):186-92. https://doi.org/10.1922/CDH_4294Vorster07PMID:30106524Links ]

25. Borremans M, Van Loco J, Van Den Meerssche P, Meunier J, Vrindts E, Goeyens L. Analysis of fluoride in toothpastes on the Belgian market. Int J Cosmet Sci. 2008 Apr;30(2):145-52. https://doi.org/10.1111/j.1468-2494.2008.00425.xLinks ]

26. Benzian H, Holmgren C, Buijs M, van Loveren C, van der Weijden F, van Palenstein Helderman W. Total and free available fluoride in toothpastes in Brunei, Cambodia, Laos, the Netherlands and Suriname. Int Dent J. 2012 Aug;62(4):213-21. https://doi.org/10.1111/j.1875-595X.2012.00116.xLinks ]

27. Thakkar VP, Rao A, Rajesh G, Shenoy R, Pai M. Fluoride content and labelling of toothpastes marketed in India. Community Dent Health. 2015 Sep;32(3):170-3. [ Links ]

28. Ministério de Salud (Peru). Guía técnica: guía de práctica clínica para la prevención, diagnóstico y tratamiento de la caries dental em niñas y niños. Dirección de Salud Bucal. Lima: Ministério de Salud; 2017. [ Links ]

29. Cury JM, Caldarelli PG, Tenuta LM. Necessity to review the Brazilian regulation about fluoride toothpastes. Rev Saude Publica. 2015 Dec;49:74-80. https://doi.org/10.1590/S0034-8910.2015049005768Links ]

30. Perazzo MF, Gomes MC, Neves ÉT, Martins CC, Paiva SM, Costa EM, et al. Oral problems and quality of life of preschool children: self-reports of children and perception of parents/caregivers. Eur J Oral Sci. 2017 Aug;125(4):272-9. https://doi.org/10.1111/eos.12359Links ]

31. Jensen O, Gabre P, Sköld UM, Birkhed D. Fluoride toothpaste and toothbrushing; knowledge, attitudes and behaviour among Swedish adolescents and adults. Swed Dent J. 2011;35(4):203-13. [ Links ]

32. Ribeiro GL, Gomes MC, Lima KC, Martins CC, Paiva SM, Granville-Garcia AF. The potential financial impact of oral health problems in the families of preschool children. Ciênc Saúde Coletiva. 2016 Apr;21(4):1217-26. https://doi.org/10.1590/1413-81232015214.09512015Links ]

Received: December 21, 2018; Revised: April 30, 2019; Accepted: May 22, 2019

Corresponding Author: Bertha Angelica Chávez E-mail: angelicachavez2008@hotmail.com

Declaration of Interests: The authors certify that they have no commercial or associative interest that represents a conflict of interest in connection with the manuscript.

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