Situational diagnosis of policies in Latin American and Caribbean countries for the use of fluoride and reduction of sugar consumption

Abstract Policy evaluation and guidance on fluoride use and sugar consumption in Latin American and Caribbean countries (LACC) may provide a scientific evidence basis for policymakers, dental professionals, civil society organizations and individuals committed to improving public oral health. A cross-sectional study was conducted to evaluate the extent of implementation of policies/guidelines on fluoride use, and sugar consumption in LACC. The study had two stages. First a questionnaire covering four major areas was developed: fluoridation of public water supplies; salt fluoridation; fluoride dentifrices, and sugar consumption. Then, the questionnaire was applied to collect data among representative participants in public oral health from LACC. Ninety-six participants from 18 LACC answered the questionnaire. One-hundred seventy documents were attached, and 285 links of websites were provided by the respondents. Implementation of policies and guidelines on water and table salt fluoridation and processed and ultra-processed food consumption were found in most countries, with some issues in the consensus and coverage. Thus, differences were identified in the extent of implementation of public oral health strategies on sugar consumption and fluoridation among the countries. There is no consensus on the policies in LACC to reduce sugar consumption and for the use of fluoride. A few policies and guidelines were applied in isolated countries, with a variety of strategies and standards. For future actions, it will be important to encourage the development of strategies and public policies within countries, and to evaluate the effectiveness of existing policies in reducing dental caries and in improving oral health in LACC.

Dose-response relationship between toothpaste soluble fluoride absorbed in the gastrointestinal tract and saliva fluoride secretion

Aim: This study aimed to evaluate if there is a dose-response relationship between toothpaste chemically soluble fluoride absorbed in the gastrointestinal tract and fluoride secreted by saliva, giving support to the use of saliva as surrogate for plasma fluoride. Methods: A 4-phase single blind study was conducted, in which 10 participants were subjected in each phase to one of the assigned treatment groups: group I: fresh sample of a Na2FPO3/CaCO3-based toothpaste with 1,334 µg F/g of total soluble fluoride (TSF) and groups II­IV: aged samples of this toothpaste presenting TSF concentrations of 1,128, 808, and 687 µg F/g, respectively. In all phases, the participants ingested an amount of toothpaste equivalent to 70.0 µg F/Kg body weight, as total fluoride (TF). Saliva and blood samples were collected before (baseline) and up to 180 min after toothpaste ingestion as indicator of fluoride bioavailability. F concentration in saliva and blood plasma was determined with a fluoride ion-specific electrode. The areas under the curve (AUC) of F concentration versus time (AUC = ng F/mL × min) and the peaks of fluoride concentration (Cmax) in saliva and plasma were calculated. Results: A significant correlation between mg of TSF ingested and the AUC (r=0.47; p<0.01), and Cmax (r=0.59; p<0.01) in saliva was found; for TF, the correlation was not significant (p>0.05). In addition, the correlations between plasma and saliva fluoride concentrations were statistically significant for AUC (r=0.55; p<0.01) as for Cmax (r=0.68; p<0.01). Conclusion: The findings support that saliva can be used as a systemic biomarker of bioavailable fluoride present in Na2FPO3/CaCO3-based toothpaste

Demystifying interactions between micro organisms in oral candidiasis biofilm: the key to enhancing treatments

Introduction: candida albicans is a fungal pathogen that can provoke diseases ranging from oral infections to life-threatening systemic disorders. It is now recognized that oral bacteria, such as the genus Streptococcus, establish synergistic relationships with C. albicans, which could potentially increase the fungi's virulence and pathogenicity. Objective: this narrative review aimed to discuss the Candida-Streptococcus mechanisms of interactions and their contribution to increasing oral candidiasis severity. In addition, it provides a background of biofilm formation and potential therapeutical targets. Sources of Data: searches for papers in English were performed in the Pubmed database until May 2022. MeSH and free terms related to the field were used. In vitro studies were selected, tabulated, and qualitative and quantitative data were analyzed descriptively. Synthesis of Data: among the early colonizers bacteria, evidence pointed out that S. gordonnii and S. oralis have major implications in oral candidiasis, in which mixed biofilms increase the infection severity and challenge the host's defense. On the other hand, the outcomes of the interaction between C. albicans and S. mitis, S. sanguinis, or S. mutans remain little explored in the oral candidiasis scenario, albeit evidence pointed out an enhanced fungus population and virulence factors. Conclusion: overall, considering the polymicrobial profile of the infection and the potential to increase Candida-related disease severity, therapeutical strategies should also consider bacteria management.

Introdução: candida albicans é um patógeno fúngico que pode provocar doenças que variam de infecções orais a distúrbios sistêmicos com risco de vida. Hoje se reconhece que as bactérias orais, como o gênero Streptococcus, estabelecem relações sinérgicas com C. albicans, o que pode potencialmente aumentar a virulência e patogenicidade do fungo. Objetivo: esta revisão narrativa teve como objetivo discutir os mecanismos de interação Candida-Streptococcus e sua contribuição para o agravamento da candidíase oral. Além disso, fornece uma breve explanação sobre a formação do biofilme e potenciais alvos terapêuticos. Fonte dos dados: foi realizada pesquisa na base de dados Pubmed para a busca de artigos publicados em Inglês até maio de 2022. Para isso, foram utilizados descritores relacionados ao tema. Estudos in vitro foram selecionados, tabulados e seus resultados quantitativos e qualitativos analisados descritivamente. Síntese dos dados: entre as bactérias denominadas colonizadores iniciais, evidências apontam que S. gordonnii e S. oralis têm implicações importantes na candidíase oral, na qual biofilmes mistos aumentam a gravidade da infecção e desafiam a defesa do hospedeiro. Por outro lado, os desfechos das interações entre C. albicans e S. mitis, S. sanguinis ou S. mutans permanecem pouco explorados no cenário da candidíase oral, apesar de evidências apontarem um aumento dapopulação fúngica e de fatores de virulência. Conclusão: de maneira geral, considerando o perfil polimicrobiano da infecção e o potencial agravamento das doenças provocadas por Candida spp, as estratégias terapêuticas não devem estar focadas apenas no fungo, mas também devem considerar o manejo da bactéria.

Fluoride concentration in toothpaste marketed to children in Brazil and Mexico, and discussion on current regulations

Resumo Os dentifrícios fluoretados comercializados para crianças devem conter concentração mínima de 1000 ppm de fluoreto (F), que deve ser quimicamente solúvel para ter efeito anticárie. Portanto, determinamos as concentrações de fluoreto total (FT) e fluoreto solúvel total (FST) em dentifrícios comercializados para crianças no Brasil e no México e analisamos as regulamentações vigentes em ambos os países. Vinte e quatro marcas foram encontradas e adquiridas no Brasil (19 formuladas com NaF/SiO2, três com Na2FPO3/CaCO3 e duas com Na2FPO3/SiO2) e seis no México (todas com NaF/SiO2). As concentrações de FT e FST foram determinadas após a compra (amostras frescas), e a estabilidade do fluoreto nas formulações de Na2FPO3/CaCO3 foi verificada após 18 meses. As análises foram realizadas com eletrodo íon-específico e os resultados expressos em ppm F (mg F/kg). As concentrações de FT encontradas variaram de 476,0 a 1.385,3 ppm F e foram próximas às declaradas pelos fabricantes (500 a 1.450 ppm F). As concentrações de FT encontradas não ultrapassaram 1.500 ppm F, de acordo com as regulamentações vigentes de ambos os países. No entanto, dentifrícios com concentrações de FST inferiores a 1.000 ppm F foram encontrados tanto em dentifrício com baixa concentração (500 ppm F) formulado com NaF/SiO2 como em dentifrícios com Na2FPO3/CaCO3 frescos e envelhecidos, originalmente fabricados com 1.000-1.100 ppm de FT. Em conclusão, embora a maioria dos dentifrícios analisados apresentasse concentração de FST superior a 1.000 ppm F, as regulamentações vigentes em ambos os países permitem que produtos que não estejam de acordo com a melhor evidência disponível estejam presentes no mercado.

Abstract Fluoride toothpastes market to children should contain a minimum concentration of 1000 ppm of fluoride (F), which must be chemically soluble to provide anti-caries effect. Therefore, we determined the concentrations of total fluoride (TF) and total soluble fluoride (TSF) in toothpastes marketed to children in Brazil and Mexico and analyzed the current regulations in force in both countries. Twenty-four brands were found and purchased in Brazil (19 formulated with NaF/SiO2, three with Na2FPO3/CaCO3 and two with Na2FPO3/SiO2) and six in Mexico (all with NaF/SiO2). TF and TSF concentrations were determined after the purchase (fresh samples) but fluoride stability in Na2FPO3/CaCO3-formulations was checked after 18 months. The analyses were performed with an ion-specific electrode and the results expressed in ppm F (mg F/kg). The TF concentrations found ranged from 476.0 to 1385.3 ppm F and they were close the declared by the manufactures (500 to 1450 ppm F). The TF concentrations found were not greater than 1500 ppm F, in accordance with the current regulations of both countries. However, toothpastes presenting TSF concentrations lower than 1000 ppm F were found either in low fluoride toothpaste (500 ppm F) formulated with NaF/SiO2 as in fresh and aged Na2FPO3/CaCO3-toothpastes, originally fabricated with 1000-1100 ppm of TF. In conclusion, although most toothpastes analyzed showed TSF concentration higher than 1000 ppm F, the regulations in force in both countries allow that products not in agreement with the best available evidence are available in the market.

Dental caries prevalence, prospects, and challenges for Latin America and Caribbean countries: a summary and final recommendations from a Regional Consensus

Abstract Dental caries can be effectively managed and prevented from developing into cavitated lesions while preserving tooth structure at all levels. However, the strong correlation between caries and socioeconomic factors may compromise the efficacy of preventive strategies. The high prevalence of persistent inequalities in dental caries in Latin American and Caribbean countries (LACC) is a matter of concern. The estimates of the burden of disease in some countries in this region are outdated or absent. This paper aims to summarize and present the final recommendations of a regional Consensus for Dental Caries Prevalence, Prospects, and Challenges for LACC. This consensus is based on four articles that were written by a team of Latin American experts, reviewed by dental associations, and presented and discussed in two consensus events. The following domains were explored: epidemiology, risk factors, prevention strategies, and management of dental caries with a focus on restorative procedures. Dental caries can manifest throughout the lifespan of an individual, making it a matter of concern for infants, children, adults, and older people alike. The prevalence rates of untreated caries in deciduous and permanent teeth are high in many parts of the world, including LACCs. Previous evidence suggests that the prevalence of dental caries in 12-year-olds is moderate to high in most Latin American countries. Moreover, the prevalence of treatment needs and dental caries in the adult and elderly population can also be regarded as high in this region. The risk/protective factors (e.g., sugar consumption, exposure to fluoride, and oral hygiene) probably operate similarly in all LACCs, although variations in the interplay of these factors in some countries and within the same country cannot be ruled out. Although salt and water fluoridation programs are implemented in many countries, there is a need for implementation of a surveillance policy. There is also room for improvement with regard to the introduction of minimal intervention techniques in practice and public health programs. Dental caries is a marker of social disadvantage, and oral health promotion programs and interventions aimed at reducing the burden of dental caries in LACCs must consider the complexity of the socioeconomic dynamics in this region. There is an urgent need to promote engagement of stakeholders, policymakers, medical personnel, universities, dental associations, community members, and industries to develop regional plans that enhance the oral health agenda for LACCs. A list of recommendations has been presented to underpin strategies aimed at reducing the prevalence and severity of dental caries and improving the quality of life of the impacted LACC population in the near future.

A simplified protocol to determine total fluoride concentration in NaF/silica-based toothpastes

Aim: To determine total fluoride (TF) concentration in Na2FPO3/Ca-based toothpastes, using fluoride ion selective electrode (F-ISE) by the direct technique, it is necessary to use acid (Ac+) to hydrolyze the FPO32- ion and to dissolve insoluble fluoride salts bound to the abrasive. For NaF/silica-based toothpastes, the use of acid is not necessary (Ac-) and a simplified protocol could be followed. Methods: Thus, we evaluated TF concentration in seven brands of NaF/silica-based toothpastes, following the validated conventional Cury's protocol (Ac+) or a simplification of this protocol (Ac-).Fluoride was analyzed with ISE calibrated with fluoride standard solutions prepared in the same conditions as the samples (Ac+ or Ac-). Results: The mean (±SD; n=21) of TF concentrations (µg F/g) found by Ac+ (971.3±191.2) and Ac- (982.4±201.3) protocols were not statistically different (t test, p=0.22). The TF concentrations found agree with those declared by the manufacturers, except for one toothpaste imported from China. Conclusion: The findings suggest that the determination of fluoride in NaF/silica-based toothpastes can be accurately made using a simplified protocol of analysis

Fluoride concentration in the top-selling Brazilian toothpastes purchased at different regions

To be relevant in terms of public health, widely-used toothpastes should have at least 1,000 ppm of soluble fluoride (F) concentration. Thus, the concentrations of total fluoride (TF) and total soluble fluoride (TSF) in the top-selling Brazilian toothpastes were evaluated. Samples (n=3) from toothpastes Colgate Anti-cáries®, Colgate Total 12 Clean Mint®, Colgate Tripla Ação Menta Original®, Colgate Tripla Ação Menta Suave® and Sorriso Dentes Brancos® were obtained from each of the five regions of the country. The concentrations of TF and TSF were analyzed with ion-specific electrode calibrated with F standards and the results were expressed in ppm (µg F/g). All toothpastes showed TF concentration lower than 1,500 ppm F (1,388.2 ± 25.8 to 1,483.2 ± 98.2). The TSF values were higher than 1,000 ppm F and ranged from 1,035.5 ± 61.5 to 1,221.8 ± 35.2 for calcium carbonate/monofluorophosphate-based toothpastes and from 1,455.6 ± 12.5 to 1,543.0 ± 147.3 for silica/sodium fluoride-based toothpaste. Top-selling Brazilian toothpastes presented available fluoride concentration to control caries regardless of the region where they are purchased.

Para ter relevância em termos de saúde pública, os cremes dentais amplamente utilizados pela população devem ter fluoreto (F) solúvel numa concentração mínima de 1.000 ppm F. Assim, as concentrações de fluoreto total (FT) e flureto solúvel total (FST) nos cremes dentais mais vendidos no Brasil foram avaliados. Os cremes dentais (n=3) Colgate Anti-cáries®, Colgate Total 12 Clean Mint®, Colgate Tripla Ação Menta Original®, Colgate Tripla Ação Menta Suave® e Sorriso Dentes Brancos® foram obtidos nas cinco regiões do país. As concentrações de FT e FST foram analisadas com eletrodo íon-específico calibrado com padrões de F e os resultados foram expressos em ppm (µg F/g). Todos os cremes dentais apresentaram concentração de FT inferior a 1.500 ppm F (1.388,2 ± 25,8 a 1.483,2 ± 98,2). Os valores de FST foram superiores a 1.000 ppm F e variaram de 1.035,5 ± 61,5 a 1.221,8 ± 35,2 para cremes dentais a base de carbonato de cálcio/monofluorfosfato e de 1.455,6 ± 12,5 a 1.543,0 ± 147,3 para o creme dental à base de sílica/fluoreto de sódio. Os cremes dentais mais vendidos no Brasil apresentaram concentração de fluoreto solúvel para controlar cárie, independentemente da região onde foram comprados.

Polytetrafluorethylene added to acrylic resins: mechanical properties

The addition of different polymers, such as polytetrafluorethylene (PTFE), to denture base resins could be an option to modify acrylic resin mechanical properties. This study evaluated the surface hardness, impact and flexural strength, flexural modulus and peak load of 2 acrylic resins, one subjected to a long and another subjected to a short polymerization cycle, which were prepared with or without the addition of 2 percent PTFE. Four groups were formed according to the polymerization cycle and addition or not of PTFE. Forty specimens were prepared for each test (10 per group) with the following dimensions: hardness (30 mm diameter x 5 mm thick), impact strength (50 x 6 x 4 mm) and flexural strength (64 x 10 x 3.3 mm) test. The results of the flexural strength test allowed calculating flexural modulus and peak of load values. All tests were performed in accordance with the ISO 1567:1999 standard. Data were analyzed statistically by ANOVA and Tukey's test with the level of significance set at 5 percent. No statistically significant differences (p>0.05) were found for surface hardness. Flexural strength, impact strength and peak load were significantly higher (p<0.05) for resins without added PTFE. The flexural modulus of the acrylic resin with incorporated 2 percent PTFE polymerized by long cycle was significantly higher (p<0.05) than that of the other resins. Within the limits of this study, it may be concluded that the addition of PTFE did not improve the mechanical properties of the evaluated acrylic resins.

A adição de diferentes polímeros como o politetrafluoretileno (PTFE) às resinas para base de próteses removíveis pode ser uma opção para modificar as propriedades mecânicas das resinas acrílicas. Este estudo avaliou a dureza de superfície, a resistência ao impacto e à flexão, o módulo flexural e a carga de ruptura de duas resinas acrílicas, uma submetida ao ciclo longo e a outra ao ciclo curto de polimerização, as quais foram preparadas com ou sem a adição de PTFE a 2 por cento. Quatro grupos foram formados de acordo com os ciclos de polimerização e a adição ou não de PTFE. Quarenta espécimes foram preparados para cada teste (10 espécimes por grupo) com as seguintes dimensões: dureza de superfície (30 mm diametro x 5 mm espessura), resistência ao impacto (50 x 6 x 4 mm), resistência à flexão (64 x 10 x 3,3 mm). O módulo flexural e a carga de ruptura foram calculados a partir dos valores obtidos no teste de resistência à flexão. Todos os testes foram realizados em conformidade com a Norma ISO 1567:1999. Os dados foram submetidos à análise de variância e teste de Tukey com nível de significância de 5 por cento. Não foram encontradas diferenças estatisticamente significantes (p>0,05) para dureza de superfície. Os valores de resistência à flexão, resistência ao impacto e carga de ruptura foram maiores para as resinas sem a adição de PTFE (p<0,05). O valor do módulo flexural da resina acrílica com adição de PTFE a 2 por cento, polimerizada por ciclo longo, foi maior do que as outras resinas (p<0,05). Dentro das limitações deste estudo, pode-se concluir que a adição de politetrafluoretileno não melhorou as propriedades mecânicas das resinas acrílicas avaliadas.

Preload loss and bacterial penetration on different implant-abutment connection systems

Preload loss can favor the occurrence of implant-abutment interface misfit, and bacterial colonization at this interface may lead to implant failure. The aim of this study was to evaluate the preload loss and bacterial penetration through the implant-abutment interface of conical and external hexagon connection systems subjected to thermal cycling and mechanical fatigue (TM). Four different implant-abutment connection systems were evaluated (n=6): external hexagon with universal post, Morse taper with universal post, Morse taper with universal post through bolt, and locking taper with standard abutment. The assemblies (implant-abutment) were subjected to a thermal cycling regimen (1,000 cycles of 5°C and 55°C) and to mechanical fatigue (1.0 million cycles, 1.0 Hz, 120 N). The assemblies were immersed in Tryptic Soy + Yeast Extract broth containing Streptococcus sanguinis and incubated at 37°C and 10 percent CO2 for 72 h. Detorque values were recorded. The bacterial penetration was assessed and the abutments were observed by scanning electron microscopy. The preload data were analyzed statistically by two-way ANOVA and Tukey’s test at 5 percent significance level. All screw abutment systems showed significantly higher (p<0.05) detorque values when subjected to TM and all conical systems presented bacterial penetration. The results show no relationship between the preload loss and the bacterial penetration.

A perda da pré-carga pode favorecer o desajuste da interface implante-pilar e a colonização bacteriana nesta interface pode levar a perda de implantes. O objetivo deste estudo foi avaliar a perda de pré-carga e a infiltração bacteriana através da interface implante-pilar de sistemas de conexão cônica e hexágono externo, submetidos à ciclagem térmica e fadiga mecânica (CF). Quatro diferentes sistemas de conexão implante-pilar foram avaliados (n=6): hexágono externo com munhão universal, cone Morse com munhão universal, cone Morse com munhão universal parafuso passante e cônica justaposição com pilar padrão. Os espécimes (implante-pilar) foram submetidos à ciclagem térmica (1000 ciclos a 5°C e 55°C) e à fadiga mecânica (1,0 milhão de ciclos, 1,0 Hz, 120 N). Os espécimes foram imersos em caldo Tryptic Soy + Yeast Extract contendo Streptococcus sanguinis e incubados a 37°C e 10 por cento de CO2 por 72 h. Os valores de destorque foram registrados. A infiltração bacteriana foi avaliada e os pilares foram observados por microscopia eletrônica de varredura. Os dados de pré-carga foram analisados estatisticamente por ANOVA a dois critérios e teste de Tukey, com nível de significância de 5 por cento. Todos os sistemas de pilares parafusados apresentaram maiores valores de destorque quando submetidos à CF (p<0,05) e todos os sistemas cônicos apresentaram infiltração bacteriana. Os resultados mostram que não houve relação entre a perda da pré-carga e a infiltração bacteriana.