Is there any association between fluoride exposure and thyroid function modulation? A systematic review.

Numerous pre-clinical and observational studies have explored the potential effects of fluoride (F) at varying concentrations on diverse systems and organs. While some have assessed the endocrinological conditions of children and adults, a consensus regarding the interaction between F and the thyroid remains elusive. This systematic review aimed to gather primary evidence on the association between F and changes in the thyroid at optimal and high levels in water supply as stipulated by the World Health Organization. A search strategy, incorporating terms pertinent to the studies, was employed across PubMed, Scopus, Web of Science, Lilacs, and Google Scholar. Following the review of studies, data were extracted and analyzed using the Grading of Recommendations, Assessment, Development, and Evaluations to assess the quality of the evidence. Our results yielded 3,568 studies, of which seven met the inclusion criteria for this review. Five of the seven studies identified an association between high F exposure and thyroid function. In the analysis of methodological quality, every study was found to have major or minor methodological issues and significant risk of bias. The overall confidence in the evidence was deemed low for all outcomes in the seven studies. The evidence compiled in this review suggests a potential association between chronic high levels of F exposure and thyroid damage. Nonetheless, further studies with robust design and high methodological quality are required to provide evidence for policy makers and health care practitioners.

Urinary fluoride levels and metal co-exposures among pregnant women in Los Angeles, California.

BACKGROUND: Fluoride is ubiquitous in the United States (US); however, data on biomarkers and patterns of fluoride exposure among US pregnant women are scarce. We examined specific gravity adjusted maternal urinary fluoride (MUFsg) in relation to sociodemographic variables and metal co-exposures among pregnant women in Los Angeles, California. METHODS: Participants were from the Maternal and Developmental Risks from Environmental and Social Stressors (MADRES) cohort. There were 293 and 490 women with MUFsg measured during first and third trimesters, respectively. An intra-class correlation coefficient examined consistency of MUFsg between trimesters. Kruskal-Wallis and Mann-Whitney U tests examined associations of MUFsg with sociodemographic variables. Covariate adjusted linear regression examined associations of MUFsg with blood metals and specific gravity adjusted urine metals among a subsample of participants within and between trimesters. A False Discovery Rate (FDR) correction accounted for multiple comparisons. RESULTS: Median (IQR) MUFsg was 0.65 (0.5) mg/L and 0.8 (0.59) mg/L, during trimesters one and three respectively. During both trimesters, MUFsg was higher among older participants, those with higher income, and White, non-Hispanic participants than Hispanic participants. MUFsg was also higher for White, non-Hispanic participants than for Black, non-Hispanic participants in trimester three, and for those with graduate training in trimester one. MUFsg was negatively associated with blood mercury in trimester one and positively associated with blood lead in trimester three. MUFsg was positively associated with various urinary metals, including antimony, barium, cadmium, cobalt, copper, lead, nickel, tin, and zinc in trimesters one and/or three. CONCLUSIONS: MUFsg levels observed were comparable to those found in pregnant women in Mexico and Canada that have been associated with poorer neurodevelopmental outcomes. Lower urinary fluoride levels among Hispanic and non-Hispanic Black participants in MADRES compared to non-Hispanic White participants may reflect lower tap water consumption or lower fluoride exposure from other sources. Additional research is needed to examine whether MUFsg levels observed among pregnant women in the US are associated with neurodevelopmental outcomes.

Financial assessment of the community-based dental education program at the Indiana University School of Dentistry.

BACKGROUND: There is a gap in access to oral health services for millions of Americans residing in health professional shortage areas. The community-based dental education program at the Indiana University School of Dentistry is an innovative model that aims to improve access to oral health services in rural underserved Indiana. OBJECTIVE: With this study, our goal was to assess the financial implications of the program over a period of 3 years (2018-2021). METHODS: Proxy estimates for the revenue generated by students at the community clinic sites were calculated and compared against the implementation costs of the program as well as revenue lost by the school during the rotation period. Descriptive statistics were used to assess the quantitative impact of the program over the 3 years. RESULTS: The total of 7460 patients who were offered care as part of this program were mostly from the uninsured group or were covered under Medicaid. According to our cost-benefit analysis which was conducted during the peak of the coronavirus disease 2019 (COVID-19) pandemic, the total revenue of $1,777,097 was generated by students at the community sites through the 3-year period. The revenue generated was still more than the dollar amount invested in running the program, given the timeline of the study was when elective services were mostly suspended. CONCLUDE: We conclude community programs like these have an impact beyond the dollar value; they can be modeled to be cost-effective, improve access to oral health services for millions of Americans in underserved settings and at the same time provide a great learning experience for dental students.

Fluoride Metabolism in Pregnant Women: A Narrative Review of the Literature.

Epidemiological studies use biomarkers of fluoride exposure in pregnant women as surrogate measures of fetal fluoride exposure; however, there is little understanding of how pregnancy affects fluoride metabolism and its biomarkers. This narrative review summarizes the changes of pregnancy that have the potential to impact fluoride's absorption, distribution and excretion, and highlights the limited body of evidence on the topic. The physiologic systems that experience pregnancy-associated changes relevant to fluoride's metabolism are the cardiovascular, renal, metabolic and gastrointestinal, as well bone and calcium metabolism and the body's acid-base balance. The available evidence indicates that fluoride is found in the maternal plasma and urine, placenta, amniotic fluid and fetus. Although plasma and urinary fluoride vary across gestation, there is insufficient quality evidence to determine the direction or extent of such variation. Furthermore, there is no doubt that fluoride from maternal blood crosses the placenta and is absorbed and excreted by the fetus; however, the biological mechanisms behind this placental passage are unknown. Research on maternal and prenatal biomarkers of fluoride exposure would benefit from studies on how pregnancy-associated changes affect the metabolism of fluoride across gestation, the mechanisms for the intestinal absorption of fluoride in pregnant women, and the placental passage of fluoride.

Dietary Influences on Urinary Fluoride over the Course of Pregnancy and at One-Year Postpartum.

Dietary factors are known to influence urinary fluoride (UF) levels in nonpregnant people. Maternal UF is used as a biomarker of fluoride exposure; however, dietary influences on UF during pregnancy are unknown. We compared UF levels and assessed the associations between UF and five select dietary influences in pregnancy vs. one-year postpartum: dietary fluoride (F), calcium intake from diet (Ca-diet), calcium intake from supplements (Ca-sup), dietary acid load (AL), and table salt use (TS) in 421 women exposed to fluoridated salt in the Mexican diet. Spot UF (mg/L) was measured by microdiffusion/fluoride-specific electrode and dilution-corrected with specific gravity (SG). Dietary variables were estimated from a validated Food Frequency Questionnaire. Comparisons among UF in pregnancy vs. one-year postpartum were performed with non-parametric tests. Associations between dietary variables and UF were assessed using random effect models (for pregnancy) and linear regression (for one-year postpartum). SG-corrected UF (median, range) during pregnancy (0.77, 0.01-4.73 mg/L) did not significantly differ from one-year postpartum (0.75, 0.15-2.62 mg/L) but did increase every 10 gestational weeks, ß = 0.05 (CI: 0.00-0.10). Different dietary influences on UF were identified at each state. Although Ca-diet and AL were not associated with UF in either state, Ca-sup decreased UF only during pregnancy, ß = - 0.012 mg/L (CI: - 0.023-0.00). Reporting TS use was associated with 12% increase in UF only at one-year postpartum (p = 0.026). These results suggest different dietary influences on UF in the pregnant state, which need consideration when using UF as a biomarker of fluoride exposure.

STABILIZED STANNOUS FLUORIDE (SnF2) TOOTHPASTES MAY BE EFFECTIVE IN THE MANAGEMENT OF HYPERSENSITIVITY, WHILE MORE RESEARCH IS NEEDED FOR ITS EFFECTIVENESS IN DENTAL CARIES AND EROSION PREVENTION.

ARTICLE TITLE AND BIBLIOGRAPHIC INFORMATION: Konradsson K, Lingström P, Emilson CG, Johannsen G, Ramberg P, Johannsen A. Stabilized stannous fluoride dentifrice in relation to dental caries, dental erosion and dentin hypersensitivity: A systematic review. Am J Dent. 2020;33(2):95-105. SOURCE OF FUNDING: Information not available. TYPE OF STUDY/DESIGN: Systematic review with meta-analysis of data.

Dietary fluoride intake during pregnancy and neurodevelopment in toddlers: A prospective study in the progress cohort.

Foods and beverages provide a source of fluoride exposure in Mexico. While high fluoride concentrations are neurotoxic, recent research suggests that exposures within the optimal range may also pose a risk to the developing brain. This prospective study examined whether dietary fluoride intake during pregnancy is associated with toddlers' neurodevelopment in 103 mother-child pairs from the PROGRESS cohort in Mexico City. Food and beverage fluoride intake was assessed in trimesters 2 and 3 using a food frequency questionnaire and Mexican tables of fluoride content. We used the Bayley-III to evaluate cognitive, motor, and language outcomes at 12 and 24 months of age. Adjusted linear regression models were generated for each neurodevelopment assessment time point (12 and 24 months). Mixed-effects models were used to consider a repeated measurement approach. Interactions between maternal fluoride intake and child sex on neurodevelopmental outcomes were tested. Median (IQR) dietary fluoride intake during pregnancy was 1.01 mg/d (0.73, 1.32). Maternal fluoride intake was not associated with cognitive, language, or motor outcomes collapsing across boys and girls. However, child sex modified the association between maternal fluoride intake and cognitive outcome (p interaction term = 0.06). A 0.5 mg/day increase in overall dietary fluoride intake was associated with a 3.50-point lower cognitive outcome in 24-month old boys (95 % CI: -6.58, -0.42); there was no statistical association with girls (ß = 0.07, 95 % CI: -2.37, 2.51), nor on the cognitive outcome at 12-months of age. Averaging across the 12- and 24-month cognitive outcomes using mixed-effects models revealed a similar association: a 0.5 mg/day increase in overall dietary fluoride intake was associated with a 3.46-point lower cognitive outcome in boys (95 % CI: -6.23, -0.70). These findings suggest that the development of nonverbal abilities in males may be more vulnerable to prenatal fluoride exposure than language or motor abilities, even at levels within the recommended intake range.

CariesCare International adapted for the pandemic in children: Caries OUT multicentre single-group interventional study protocol.

BACKGROUND: Comprehensive caries care has shown effectiveness in controlling caries progression and improving health outcomes by controlling caries risk, preventing initial-caries lesions progression, and patient satisfaction. To date, the caries-progression control effectiveness of the patient-centred risk-based CariesCare International (CCI) system, derived from ICCMS™ for the practice (2019), remains unproven. With the onset of the COVID-19 pandemic a previously planned multi-centre RCT shifted to this "Caries OUT" study, aiming to assess in a single-intervention group in children, the caries-control effectiveness of CCI adapted for the pandemic with non-aerosols generating procedures (non-AGP) and reducing in-office time. METHODS: In this 1-year multi-centre single-group interventional trial the adapted-CCI effectiveness will be assessed in one single group in terms of tooth-surface level caries progression control, and secondarily, individual-level caries progression control, children's oral-health behaviour change, parents' and dentists' process acceptability, and costs exploration. A sample size of 258 3-5 and 6-8 years old patients was calculated after removing half from the previous RCT, allowing for a 25% dropout, including generally health children (27 per centre). The single-group intervention will be the adapted-CCI 4D-cycle caries care, with non-AGP and reduced in-office appointments' time. A trained examiner per centre will conduct examinations at baseline, at 5-5.5 months (3 months after basic management), 8.5 and 12 months, assessing the child's CCI caries risk and oral-health behaviour, visually staging and assessing caries-lesions severity and activity without air-drying (ICDAS-merged Epi); fillings/sealants; missing/dental-sepsis teeth, and tooth symptoms, synthetizing together with parent and external-trained dental practitioner (DP) the patient- and tooth-surface level diagnoses and personalised care plan. DP will deliver the adapted-CCI caries care. Parents' and dentists' process acceptability will be assessed via Treatment-Evaluation-Inventory questionnaires, and costs in terms of number of appointments and activities. Twenty-one centres in 13 countries will participate. DISCUSSION: The results of Caries OUT adapted for the pandemic will provide clinical data that could help support shifting the caries care in children towards individualised oral-health behaviour improvement and tooth-preserving care, improving health outcomes, and explore if the caries progression can be controlled during the pandemic by conducting non-AGP and reducing in-office time. TRIAL REGISTRATION: Retrospectively-registered-ClinicalTrials.gov-NCT04666597-07/12/2020: https://register.clinicaltrials.gov/prs/app/action/SelectProtocol?sid=S000AGM4&selectaction=Edit&uid=U00019IE&ts=2&cx=uwje3h . Protocol-version 2: 27/01/2021.

Critical windows of fluoride neurotoxicity in Canadian children.

BACKGROUND: Fluoride has been associated with IQ deficits during early brain development, but the period in which children are most sensitive is unknown. OBJECTIVE: We assessed effects of fluoride on IQ scores across prenatal and postnatal exposure windows. METHODS: We used repeated exposures from 596 mother-child pairs in the Maternal-Infant Research on Environmental Chemicals pregnancy and birth cohort. Fluoride was measured in urine (mg/L) collected from women during pregnancy and in their children between 1.9 and 4.4 years; urinary fluoride was adjusted for specific gravity. We estimated infant fluoride exposure (mg/day) using water fluoride concentration and duration of formula-feeding over the first year of life. Intelligence was assessed at 3-4 years using the Wechsler Preschool and Primary Scale of Intelligence-III. We used generalized estimating equations to examine the associations between fluoride exposures and IQ, adjusting for covariates. We report results based on standardized exposures given their varying units of measurement. RESULTS: The association between fluoride and performance IQ (PIQ) significantly differed across prenatal, infancy, and childhood exposure windows collapsing across child sex (p = .001). The strongest association between fluoride and PIQ was during the prenatal window, B = -2.36, 95% CI: -3.63, -1.08; the association was also significant during infancy, B = -2.11, 95% CI: -3.45, -0.76, but weaker in childhood, B = -1.51, 95% CI: -2.90, -0.12. Within sex, the association between fluoride and PIQ significantly differed across the three exposure windows (boys: p = .01; girls: p = .01); among boys, the strongest association was during the prenatal window, B = -3.01, 95% CI: -4.60, -1.42, whereas among girls, the strongest association was during infancy, B = -2.71, 95% CI: -4.59, -0.83. Full-scale IQ estimates were weaker than PIQ estimates for every window. Fluoride was not significantly associated with Verbal IQ across any exposure window. CONCLUSION: Associations between fluoride exposure and PIQ differed based on timing of exposure. The prenatal window may be critical for boys, whereas infancy may be a critical window for girls.

Association of Dietary Fluoride Intake and Diet Variables with Dental Caries in Adolescents from the ELEMENT Cohort Study.

To examine the association of dietary fluoride intake, total carbohydrate consumption and other key dietary variables with dental caries experience among adolescents, a cross-sectional analysis was conducted in a sample of 402 participants from the Early Life Exposures in Mexico to Environmental Toxicants cohort. The presence and severity of dental caries were assessed using the International Caries Detection and Assessment System (ICDAS) to calculate the number of decayed, missing, and filled teeth or surfaces (D1MFT/D4MFT). The dietary intake of fluoride, energy, carbohydrates, and food groups was estimated using a validated food frequency questionnaire (FFQ). Multivariate zero-inflated negative binomial regression models and negative binomial regression models were run to estimate the association of fluoride intake (mg/day) and total carbohydrate intake (g/day) with the D1MFT/D4MFT index. We found that 80% of the adolescents experienced dental caries (D1MFT >0), with 30% presenting cavitated lesions (D4MFT >0). The mean scores for D1MFT and D4MFT were 6.2 (SD 5.3) and 0.67 (SD 1.3), respectively. The median intake of fluoride estimated by the FFQ was 0.015 mg/kg/day. This intake was statistically higher in participants with a D4MFT = 0 compared to those with a D4MFT >0 (0.90 vs. 0.82 mg/day; 0.016 vs. 0.014 mg/kg/day; p < 0.05). For D1MFT, D1MFS, D4MFT, and D4MFS scores, a higher fluoride consumption (mg/day) from foods and beverages was associated with a statistically significant reduction in the number of lesions. The reported frequency of consumption of sugary foods in a whole day was statistically higher in those with D1MFT >0 than in those with D1MFT = 0 (p < 0.05). The total carbohydrate intake (g/day) was positively associated with dental caries experience. We conclude that a higher fluoride intake through foods and beverages is associated with a lower dental caries experience among adolescents; this effect was seen even when the dietary intake of fluoride was 0.015 mg/kg/day, which is lower than the average intake recommendation. In contrast, a higher total carbohydrate intake and the frequency of intake of sugary foods were associated with a higher dental caries experience, with no apparent threshold for the effects.

Epidemiology of Erosive Tooth Wear, Dental Fluorosis and Molar Incisor Hypomineralization in the American Continent.

Non-carious dental lesions such as developmental defects of enamel (DDE) and erosive tooth wear (ETW) are the subject of intensive research. This paper aims to give perspectives on both DDE, including dental fluorosis and molar incisor hypomineralization (MIH), and ETW, presenting epidemiological data from the Americas and associated diagnostic aspects. Besides, it is important to present evidence to guide the clinical assessment process, supporting the clinicians' management decisions towards better oral health of their patients. The overall increase in the worldwide prevalence of non-carious lesions discussed in this this paper may reflect the need of perceptual changes. Although the number of publications related to these conditions has been increasing in the last years, there is still a need for clinical diagnostic and management awareness to include these conditions in routine dental practice. Besides, it is important to provide recommendations for standardized clinical assessment criteria, improving the process and helping clinicians' adherence. In this sense, this paper discusses the most commonly implemented indices for each condition. Thus, despite the wide range of diagnostic indices, BEWE is proposed to be the index recommended for ETW assessment, Dean or Thylstrup & Fejerskov indices for fluorosis and preferably the EAPD criteria (or modified DDE index) for MIH. Overall, non-carious lesions are a growing concern, and it is important to implement preventive measures that control their severity and progression, and accurate diagnosis by the dental clinician.

Redesign of an informed consent form to increase participation in a school-based dental program.

OBJECTIVES: The study aimed to determine if modifications to the design of a consent form and consenting process increased participation rates in the Indiana University School of Dentistry's Mobile School-Based Dental Program (Seal Indiana). METHODS: Kaizen methodology was followed to identify problem areas in the consenting process. Additionally, stakeholders were invited to participate in focus groups and fill out surveys to identify issues preventing participation in the Seal Indiana program (N = 48) and later to evaluate the changes made (N = 48). The redesigned form and process were then used in a pilot study at 14 sites to determine the impact that changes had on levels of participation as measured by the number of consent forms completed and returned. RESULTS: There was a statistically significant increase in the number of consent forms returned. The measured change represented a 32 percent increase in program participation (P value = 0.035). A statistically significant increase was observed in how participants viewed the attractiveness of the form and how easy it was to read and comprehend. CONCLUSIONS: In order to increase consenting rates, our results indicate modifications to the consent form should be focused on the following characteristics: esthetics, ease of reading and comprehending information, and making the Health Insurance Portability and Accountability Act of 1996 (HIPPA) privacy regulations easier to read and comprehend.

Aesthetical perception of dental fluorosis in a Colombian low income community / Percepção estética da fluorose dentária em uma comunidade colombiana de baixa renda / Percepción estética de la fluorosis dental en una comunidad colombiana de bajos ingresos

Abstract Introduction and objective: The Dental Fluorosis (DF) is a development defect of enamel resulting from overexposure to fluoride and can aesthetically compromise the patient. This study aims to investigate the relationship between aesthetic perception and dental fluorosis (DF) in a low-income community with high DF prevalence. Materials and methods: A cross-sectional study was conducted with 171 Colombian schoolchildren aged 8 to 12 years living in low socioeconomic community (El Cedro, district of Ayapel, Córdoba, Colombia). After receiving authorization, the students were examined for DMFT and dmft indexes (WHO criteria), and for DF (TF index). The aesthetic perceptions were verified by the Child Perceptions Questionnaire About Tooth Appearance (CQATA). Data analysis was carried out using descriptive statistics, the chi-square test, the Student´s t-test, the one-way ANOVA test, and linear regression at a significance level of p ≤ 0.05. Results: The prevalence of DF in this sample was 84.8% (n=145). Only the presence of caries (DMFT/ deft≠ 0) had a significant impact on aesthetic perceptions. A significantly lower rate was found in girls for the report of pleasant color domain. The number of teeth affected by DF had a significant positive correlation with mean overall perception of dental health. Conclusion: The presence of mild DF in children with low socioeconomic status, from a population with a high prevalence of the condition, did not seem to have an impact on the report of pleasant color of teeth domain.

Resumo Introdução e Objetivo: A fluorose dentária (FD) é um defeito de desenvolvimento do esmalte decorrente da sobre-exposição ao flúor e pode comprometer esteticamente o paciente. O presente estudo se propõe a investigar a relação entre percepção estética e fluorose dentária em uma comunidade de baixa renda com alta prevalência de FD. Materiais e métodos: Foi realizado um estudo transversal com 171 escolares colombianos de 8 a 12 anos de idade, moradores de uma comunidade de baixa renda (El Cedro, distrito de Ayapel, Córdoba, Colômbia). Após receber autorização, os estudantes foram examinados para os índices CPOD e ceod (OMS) e para o FD (TF index). As percepções estéticas foram verificadas pelo "Child Perception Questionaire about Teeth Appearence" (CQATA). A análise dos dados foi realizada por meio de estatística descritiva, teste do qui-quadrado, teste t de Student, teste ANOVA one-way e regressão linear em nível de significância de p ≤ 0,05. Resultados: A prevalência de FD nesta amostra foi de 84,8% (n = 145). Apenas a presença de cáries (CPOD/cpod≠0) teve um impacto significativo nas percepções estéticas. Uma taxa significativamente menor foi encontrada em meninas para o relato de domínio de cor agradável. O número de dentes afetados pela FD teve correlação positiva significativa com a percepção geral da saúde bucal. Conclusão: A presença de FD leve em crianças com baixo nível socioeconômico, de uma população com alta prevalência da doença, não parece ter impacto na satisfação com a coloração dos dentes.

Resumen Introducción y objetivo: La fluorosis dental (FD) es un defecto en el desarrollo del esmalte como resultado de la sobreexposición al fluoruro y puede comprometer estéticamente al paciente. Este estudio tiene como objetivo investigar la relación entre la percepción estética y la fluorosis dental en una comunidad de bajos ingresos económicos y con alta prevalencia de FD. Materiales y métodos: Se realizó un estudio transversal con 171 escolares de 8 a 12 años que viven en una comunidad socioeconómica baja (El Cedro, distrito de Ayapel, Córdoba, Colombia). Los estudiantes fueron examinados para caries dentaria (índices DMFT y dmft (criterios de la OMS) y para el fluorosis dentaria (índice TF). La percepción estética se verifico con el cuestionario sobre percepciones de los niños sobre la apariencia de los dientes (CQATA). El análisis de los datos se realizó mediante estadísticas descriptivas y las pruebas de chi cuadrado, t de Student, ANOVA de una vía y la regresión lineal (p ≤ 0.05). Resultados: La prevalencia de FD fue de 84.8% (n = 145). Solo la presencia de caries (DMFT/deft ≠ 0) tuvo un impacto significativo en las percepciones estéticas. Se encontró una tasa significativamente más baja en las niñas para el informe acerca de color agradable. La cantidad de dientes afectados por FD tuvo una correlación positiva significativa con la percepción general de la salud dental. Conclusión: La presencia de FD leve en niños con bajo nivel socioeconómico, en una población con una alta prevalencia de este defecto de esmalte, no pareció tener tuvo un impacto en la aceptción aceptar la apariencia del color de los dientes.

Associations between Urinary, Dietary, and Water Fluoride Concentrations among Children in Mexico and Canada.

Fluoride, which may be toxic to the developing brain, is added to salt in Mexico and drinking water in Canada to prevent dental caries. We compared childhood urinary fluoride (CUF) concentrations in Mexico City and Canada to characterize patterns of fluoride exposure in these two populations. We also examined associations of CUF with dietary and water fluoride levels in Mexico City and Canada respectively. We included 561 children (ages 4­6; mean age 4.8 years) from the Programming Research in Obesity, Growth, Environment, and Social Stress (PROGRESS) cohort in Mexico City, and 645 children (ages 2­6; mean age 3.7 years) from the Maternal­Infant Research on Environmental Chemicals (MIREC) cohort in Canada. We applied Spearman correlations, T-tests, ANOVA or covariate-adjusted linear regression to examine associations of CUF (mg/L; adjusted for specific gravity) with demographics and dietary or water fluoride concentrations. We used Welch equivalence testing to compare means across cohorts. Mean (SD) CUF was equivalent (t = 4.26, p < 0.001) in PROGRESS: 0.74 (0.42) and fluoridated Canadian communities: 0.66 (0.47), but lower in non-fluoridated Canadian communities: 0.42 (0.31) (t = −6.37, p < 0.001). Water fluoride concentrations were significantly associated with CUF after covariate adjustment for age and sex in MIREC (B = 0.44, 95% CI: 0.30, 0.59, p < 0.001). In contrast, daily food and beverage fluoride intake was not associated with CUF in PROGRESS (p = 0.82). We found that CUF levels are comparable among children in Mexico City and fluoridated Canadian communities, despite distinct sources of exposure. Community water fluoridation is a major source of fluoride exposure for Canadian children.

Chapter 6: Vitamins and Oral Health.

Vitamins are essential organic compounds that catalyze metabolic reactions. They also function as electron donors, antioxidants or transcription effectors. They can be extracted from food and supplements, or in some cases, synthesized by our body or gut microbiome. Severe vitamin deficiencies result in systemic complications, including the development of scurvy, rickets, pellagra, and beriberi. Some moderate and severe deficiencies also result in oral conditions. A lower intake of vitamin A has been associated with decreased oral epithelial development, impaired tooth formation, enamel hypoplasia and periodontitis. Vitamin D deficiency during tooth development may result in non-syndromic amelogenesis and dentinogenesis imperfecta, enamel and dentin hypoplasia, and dysplasia. Clinical studies have demonstrated an association between vitamin D's endocrine effects and periodontitis. On the other hand, no significant association has been found between cariogenic activity and vitamin D deficiency. Vitamin C deficiency results in changes in the gingivae and bone, as well as xerostomia; while vitamin B deficiencies are associated with recurrent aphthous stomatitis, enamel hypomineralization, cheilosis, cheilitis, halitosis, gingivitis, glossitis, atrophy of the lingual papillae, stomatitis, rashes around the nose, dysphagia, and pallor. The effects of vitamins E and K on oral health are not as clear as those of other vitamins. However, vitamin K has a systemic effect (increasing the risk of haemorrhage), which may affect individuals undergoing oral surgery or suffering an oral injury. Health care professionals need to be aware of the effects of vitamins on oral health to provide the best available care for their patients.