Hipoclorito de Sodio como Agente Desproteinizante para Mejorar la Adhesión en Esmalte Hipomineralizado en Ortodoncia. Una Revisión Narrativa

Obtener una buena adhesión entre esmalte y bracket es un aspecto fundamental para el éxito del tratamiento en Ortodoncia. Algunos casos presentan desafíos en esta adhesión, especialmente cuando nos enfrentamos ante un esmalte con alteraciones como hipomineralizaciones, hipoplasias o fluorosis dental. Para sobreponer esta dificultad en la unión adhesiva se han propuesto diversas estrategias terapéuticas como es el uso de agentes desproteinizantes. El objetivo de esta revisión narrativa es describir el uso de hipoclorito de sodio como agente desproteinizante en dientes con alteraciones de esmalte para mejorar la adhesión en Ortodoncia. Se realizó una búsqueda bibliográfica en PubMed de los últimos 5 años. Se encontraron 116 artículos, de los cuales 23 cumplieron con los criterios requeridos y fueron seleccionados para la revisión. La desproteinización del esmalte con hipoclorito de sodio como paso previo al grabado ácido, es una estrategia útil en el proceso de cementación de aparatología de ortodoncia fija en dientes con alteraciones del esmalte. El uso de hipoclorito de sodio al 5,25 % es una alternativa de bajo co sto, no invasiva y eficiente para mejorar la fuerza de adhesión en pacientes con alteraciones del esmalte.

Obtaining good adhesion between enamel and bracket is a fundamental aspect for success in Orthodontics. Some cases present challenges in this adhesion, especially when we are faced with enamel with alterations such as hypomineralization, hypoplasia or dental fluorosis. To overcome this difficulty in adhesive bonding, various therapeutic strategies have been proposed, such as the use of deproteinizing agents. The objective of this study is to describe the use of sodium hypochlorite as a deproteinizing agent in teeth with enamel alterations to improve adhesion in Orthodontics. A bibliographic search was carried out in PubMed for articles within the last 5 years. In this study 116 articles were found, of which 23 met the required criteria and were selected for the review. Deproteinization of the enamel with sodium hypochlorite as a prior step to acid etching is an important stage in the cementation process of fixed appliances in orthodontics. The use of 5.25% sodium hypochlorite is a low-cost, non-invasive and efficient alternative to improve adhesion strength in patients with anomalies of tooth enamel.

Research progress on histone acetylation/methylation in oral diseases / 口腔疾病防治

@#Histone acetylation and methylation can affect chromatin conformation and regulate a variety of biological activities. Abnormal histone acetylation and methylation modifications are related to the occurrence and development of a variety of oral diseases. Histone acetylation and methylation increase or decrease in an orderly manner to regulate the development of teeth. Fluoride ions can destroy the balance between histone acetylation and methylation, which may be related to the occurrence of dental fluorosis. In addition, histone acetylation and methylation are involved in the regulation of oral inflammatory diseases. In the inflammatory microenvironment, the expression of histone acetyltransferase GCN5 decreases, and the expression of Dickkopf 1 (DKK1) decreases, activating the Wnt/β-catenin pathway and ultimately inhibiting the osteogenic differentiation of periodontal ligament stem cells. Enhancer of zeste homolog 2 (EZH2) and H3K27me3 levels were decreased in inflamed dental pulp tissues and cells. EZH2 inhibition inhibited the expression of interleukin (IL)-1b, IL-6 and IL-8 in human dental pulp cells under inflammatory stimulation. Histone acetylation/methylation modifications can interact with multiple signaling pathways to promote the occurrence and development of oral tumors and are related to the high invasiveness of salivary gland tumors. Small molecule drugs targeting histone acetylation and methylation-related enzymes can regulate the level of histone methylation/acetylation and have shown potential in the treatment of oral and maxillofacial diseases. For example, the histone deacetylase inhibitor vorinostat can inhibit the secretion of inflammation-related cytokines; it also promotes the maturation of odontoblasts and the formation of dentin-related matrix, demonstrating its potential in pulp preservation. Understanding the role of histone acetylation/methylation modifications in the occurrence and development of oral diseases will help promote research on epigenetic modifications in oral diseases and provide new perspectives for disease diagnosis and treatment.

Expression of N-methyl-D-aspartic acid receptor and endoplasmic reticulum stress related pathway proteins in brain tissue of fluorosis rats / 中国组织工程研究

BACKGROUND:Previous studies have shown that N-methyl-D-aspartic acid receptor(NMDA)receptors are associated with fluorine,but the role in fluoride-induced endoplasmic reticulum stress remains unclear. OBJECTIVE:To observe the changes of excitatory neurotransmitter NMDA receptor and endoplasmic reticulum stress IRE1α-ASK1-JNK pathway protein expression in brain tissue of rats with experimental fluorosis,and to investigate the pathogenesis of neurological injury in fluorosis by giving NMDA receptor inhibitor to SH-SY5Y cells. METHODS:(1)Animal model:18 1-month-old SD rats were randomly divided into control group(drinking water fluoride content<0.5 mg/L),low fluoride group(drinking water fluoride content 10.0 mg/L)and high fluoride group(drinking water fluoride content 100.0 mg/L),with 6 rats in each group,half of each sex.After 6 months of fluoride intake,the rats were observed for the occurrence of dental fluorosis,and the 24-hour urinary fluoride content was measured.After anesthesia and euthanasia,the brain tissue of rats was taken to observe the pathological changes.Western blot assay was used to detect NMDA receptors and IRE1α,ASK1 and JNK protein expression in the brain tissue.(2)Cell model:SH-SY5Y cells were cultured in vitro and treated with sodium fluoride at final concentrations of 0.3 mmol/L and 3 mmol/L.The fluoride-stained cells were interfered with 10 μmol/L NMDA receptor antagonists Ifenprodil and MK-801 to observe the relevant protein changes. RESULTS AND CONCLUSION:(1)The incidence of dental fluorosis and urinary fluoride level in rats in the high fluoride group were significantly higher than that in the control and low fluoride groups(P<0.05).(2)Compared with the control group,the cytoplasm of neuronal cells in the CA3 area of the hippocampus in the low fluoride group was slightly more basophilic,while the neuronal cells in the CA3 area of the high fluoride group were disorganized,with increased basophilicity and some of the nuclei solidified.(3)In rat brain tissue,the expressions of NR2A in the high fluoride group and NR2B in the low fluoride group were significantly higher compared with the control group(P<0.05),and NR2B,IRE1,ASK1,and p-JNK protein expression levels were increased in the high fluoride group compared with the control and low fluoride groups(P<0.05).(4)In SH-SY5Y cells,NR1,NR2A and NR2B protein expressions were significantly increased in the high fluoride group compared to the control group(P<0.05).The protein levels of NR1 and NR2A were significantly reduced in the high fluorine + Ifenprodil group and high fluorine + MK-801 group compared with the high fluorine group(P<0.05).NR2B protein expression was significantly lower in the high fluorine + Ifenprodil group than that in the high fluorine group(P<0.05).(5)In SH-SY5Y cells,IRE1,ASK1,and p-JNK protein expression was significantly higher in the high fluoride group compared with the control group(P<0.05),while ASK1 and p-JNK protein expressions were significantly decreased in the high fluorine + Ifenprodil group and high fluorine + MK-801 group compared with the high fluorine group(P<0.05).IRE1 protein level was significantly lower in the high fluorine + Ifenprodil group than that in the high fluorine group(P<0.05).(6)It is concluded that excessive fluorine intake activates NMDA receptors in the central nervous system,causing increased expression of endoplasmic reticulum stress IRE1α,ASK1,and p-JNK proteins,and the use of NMDA receptor inhibitors has a mitigating effect on endoplasmic reticulum stress caused by fluorosis.

Screening and analysis of differentially expressed genes for calcium homeostasis in ameloblasts with high fluoride intervention / 中国组织工程研究

BACKGROUND:Fluorosis is a disorder of enamel development caused by long-term intake of large amounts of fluoride during enamel development. OBJECTIVE:To further explore the molecular mechanism of dental fluorosis formation by screening the differentially expressed genes associated with calcium homeostasis in ameloblasts by transcriptome sequencing technology. METHODS:LS8 cells were treated with 0,0.4,0.8,1.6,3.2 and 6.4 mmol/L sodium fluoride(NaF)for 24,48 and 72 hours to observe the effects of different concentrations of NaF on the morphology,cell activity and intracellular Ca2+ concentration of LS8 cells.The differentially expressed genes were screened by transcriptome sequencing and validated. RESULTS AND CONCLUSION:After 24 hours of treatment,the cells treated with 0,0.4,and 0.8 mmol/L NaF were in good growth condition,with increased cell number and clear cell outline.When the NaF concentration was≥1.6 mmol/L,the cells were gradually shrunken and became smaller and the number of cells decreased with the increase of NaF concentration.After 48 and 72 hours of treatment,the number of cells increased in the 0,0.4 mmol/L NaF groups,while gradually decreased in the 0.8,1.6,3.2 mmol/L NaF groups,with rounded and smaller cell morphology.The cells in the 6.4 mmol/L NaF group were shrunken,rounded and suspended in the medium,with almost no adherent cells.When treated with the same concentration of NaF,LS8 cells were in optimal growth after 24 hours of treatment.Results from cell counting kit-8 assay showed that when treated with the same concentration of NaF,the cell activity decreased with the increase of treatment time;when the treatment time was the same,the cell activity decreased with the increase of NaF concentration.After 24 hours of treatment,the intracellular Ca2+ concentration increased with the increase of NaF concentration.Transcriptome sequencing analysis identified genes involved in the regulation of cellular calcium homeostasis:Hsp90b1,Canx,Calr,and Hspa5 that were significantly upregulated(P＜0.05)and Cacna1a that was significantly downregulated(P＜0.05).To conclude,the inhibitory effect of NaF on LS8 cell proliferation may be related to the abnormal increase in intracellular Ca2+ concentration,and the mechanism may be caused by the upregulation of the expression of protein processing and synthesis pathways Hsp90b1,Canx,Calr,and Hspa5 and the downregulation of the expression of calcium signaling pathway Cacna1a.

Monitoring results of drinking water-type endemic fluorosis in Xinjiang Production and Construction Corps in 2022 / 中华地方病学杂志

Objective:To investigate the control situation of drinking water-type endemic fluorosis (hereinafter referred to as drinking water fluorosis) in Xinjiang Production and Construction Corps (hereinafter referred to as the Corps), identify weak links in prevention and control, and provide reference for precise prevention and control of drinking water fluorosis in the Corps.Methods:Monitoring data of drinking water fluorosis areas in the Corps from January to December 2022 were collected from the Corps Center for Disease Control and Prevention, the level of fluoride in drinking water and the prevalence of dental fluorosis in children aged 8 - 12 were analyzed retrospectively.Results:In 2022, the qualified rate of water fluoride in the disease affected TuanChang of the Corps was 100.00% (62/62), and the qualified rate of water fluoride in the disease affected company was 99.44% (705/709). The prevalence of dental fluorosis in children aged 8 - 12 in the disease affected TuanChang was 3.38% (1 412/41 714), and there was no statistically significant difference in the prevalence of dental fluorosis among different age groups (χ 2 = 6.07, P = 0.194). The prevalence of dental fluorosis in children aged 8 - 12 in the TuanChang where the company with water fluoride exceeding standard was located (6.00%, 106/1 768) was higher than that in the TuanChang where the company with qualified water fluoride was located (3.27%, 1 306/39 946, χ 2 = 38.47, P < 0.001). Conclusion:In 2022, the drinking water fluorosis in the Corps has reached the control standard, but attention still should be paid to the water improvement situation and maintenance of water improvement projects in some water fluoride exceeding standard companies, in order to prevent sustained dental fluorosis damage to children in the affected areas, and consolidate the achievements of prevention and control.

Investigation and analysis of adult skeletal fluorosis caused by drinking tea-type endemic fluorosis in Yushu Tibetan Autonomous Prefecture, Qinghai Province in 2021 / 中华地方病学杂志

Objective:To investigate the prevalence of adult skeletal fluorosis caused by drinking tea-type endemic fluorosis in Yushu Tibetan Autonomous Prefecture (hereinafter referred to as Yushu Prefecture), Qinghai Province, and provide scientific basis for prevention and control of the disease.Methods:In August 2021, one village was selected as a survey site in six counties (cities) in Yushu Prefecture, including Nangqian, Chindu, Yushu, Zadoi, Qumarlêb, and Zhiduo. Drinking water samples and 10 brick tea samples were collected from each village to determine the fluoride content in water and brick tea; at least 100 permanent residents aged ≥ 25, who had a habit of drinking brick tea and had lived in the local area for more than 5 years, were selected for X-ray imaging to examine the prevalence of adult skeletal fluorosis.Results:A total of 75 samples of residential drinking water were collected, with a fluoride content of (0.21 ± 0.05) mg/L, ranging from 0.11 to 0.34 mg/L; 60 samples of brick tea, with a fluoride content of (626.70 ± 157.27) mg/kg, ranging from 324.00 to 2 102.00 mg/kg. A total of 1 136 adults were examined, and 318 cases of skeletal fluorosis were diagnosed, with a detection rate of 27.99%. Among them, the detection rates of mild, moderate, and severe skeletal fluorosis were 20.95% (238/1 136), 6.07% (69/1 136), and 0.97% (11/1 136), respectively, with mild symptoms being the main. The detection rates of skeletal fluorosis in males and females were 29.09% (121/416) and 27.36% (197/720), respectively, with no statistically significant difference between the gender (χ 2 = 0.39, P = 0.533). Comparison of the skeletal fluorosis in different gender, the differences were statistically significant (χ 2 = 22.31, P < 0.001). The detection rates of skeletal fluorosis in the age groups of 25 - 35, 36 - 45, 46 - 55, 56 - 65, 66 - 75, and ≥76 years old were 6.86% (7/102), 22.37% (51/228), 24.02% (92/383), 37.44% (73/195), 43.48% (70/161), and 37.31% (25/67), respectively. The differences between the groups were statistically significant (χ 2 = 59.84, P < 0.001). Moreover, there was a statistically significant difference in the composition of skeletal fluorosis among different age groups ( H = 37.66, P < 0.001). The Spearman correlation analysis results showed that the severity of adult skeletal fluorosis was positively correlated with age ( r = 0.34, P < 0.001). Conclusions:There is a certain degree of prevalence of adult skeletal fluorosis in Yushu Prefecture. And as age increases, the condition of skeletal fluorosis becomes more severe.

Growth and development status and related factors of children in drinking-water-borne endemic fluorosis area after water improvement in Xi'an / 中华地方病学杂志

Objective:To investigate the current situation and related factors of children's growth and development in drinking-water-borne endemic fluorosis areas after water improvement, and provide a basis for improving the control strategies.Methods:The stratified random sampling method was used to select children aged 7 to 13 in villages with different years of water improvement in Xi'an from November 2019 to June 2020. The height and weight of children were measured, and body mass index (BMI) was calculated. The height development level of children was graded according to the "Standard for Height Level Classification among Children and Adolescents Aged 7 - 18 Years" (WS/T 612-2018), and the physical development (BMI) level of children was determined according to the "Comprehensive Evaluation of Development Level for Children and Adolescents" (GB/T 31178-2014). At the same time, according to the standard of "Diagnosis of Dental Fluorosis" (WS/T 208-2011), the diagnosis of dental fluorosis in children was performed. The serum fluoride level was determined by ion selective electrode method, and the levels of other chemical elements (calcium, iron, magnesium, copper, zinc, iodine, selenium, lead, arsenic, cadmium, chromium, mercury, nickel) in blood were determined by inductively coupled plasma mass spectrometry.Results:A total of 469 children were included in the investigation. After water improvement, 67.38% (316/469) of the children in the disease area were at the moderate level of height development, 7.89% (37/469) were at the medium to upper and upper levels, and 24.73% (116/469) were at the medium to lower and lower levels. The BMI of the children in the emaciation group was 8.53% (40/469), while it was 10.87% (51/469) in the overweight group and 8.74% (41/469) in the obesity group. There was statistically significant difference in the distribution of height development level of children in areas with different water improvement years ( P = 0.005), but no statistically significant difference in BMI distribution ( P = 0.154). There was no significant difference in height development level and BMI distribution of children with or without dental fluorosis ( P > 0.05). There were significant differences in serum levels of iron and zinc among children with different height development levels ( P < 0.05). There were significant differences in serum levels of magnesium, copper, iodine and chromium among children with different BMI ( P < 0.05). Conclusion:The growth and development of children in drinking-water-borne endemic fluorosis area after water improvement are not correlated with the prevalence of dental fluorosis, but may be related to the levels of chemical elements such as iron, magnesium, copper, and iodine in the body.

Epidemiologia de la Fluorosis Dental en adolescentes de 12 años: Revisión sistemática

La prevalencia de fluorosis dental presenta una gran variabilidad a nivel mundial. Es necesario su análisis como parte de la vigilancia epidemiológica. Objetivo: Conocer la literatura disponible sobre prevalencia de fluorosis dental a la edad de 12 años en relación con el método de fluoruración comunitario utilizado. Metodología: Dos investigadoras realizaron una revisión sistemática de la literatura sin límites temporales siguiendo las pautas PRISMA, utilizando las bases de datos Pubmed, Cochrane, Scopus, BVS y Google Schoolar en idioma inglés, español, portugués e italiano. Resultados: Fueron incluidos 19 artículos de diseño transversal, 16 pertenecientes a comunidades que utilizan agua fluorurada, uno que utiliza sal fluorurada y 2 que comparan resultados entre comunidades que utilizan agua o sal fluorurada. Conclusiones: existe gran variabilidad en los reportes de prevalencia de fluorosis dental. Independientemente del método de fluoruración comunitario utilizado las lesiones de fluorosis de severidad leve son las más prevalentes.

Os relatos sobre a prevalência de fluorose dentária aos 12 anos apresentam grande variabilidade, não havendo unificação quanto ao uso dos índices. Independentemente do meio comunitário de fluoretação e do índice utilizado, a fluorose dentária leve é ​​a mais prevalente. Objetivo: Conhecer a literatura disponível sobre prevalência de fluorose dentária aos 12 anos em relação ao método comunitário de fluoretação utilizado. Metodologia: Dois pesquisadores realizaram uma revisão sistemática da literatura sem limites de tempo seguindo as diretrizes PRISMA, utilizando as bases de dados Pubmed, Cochrane, Scopus, BVS e Google Schoolar em inglês, espanhol, português e italiano. Resultados: Foram incluídos 19 artigos transversais, sendo 16 pertencentes a comunidades que utilizam água fluoretada, un sal fluoretada e 2 que comparam resultados entre comunidades que utilizam água fluoretada ou salgada. Conclusões: Há grande variabilidade nos relatos de prevalência de fluorose dentária. Independentemente do método de fluoretação comunitária utilizado, as lesões de fluorose de gravidade leve são as mais prevalentes.

The prevalence of dental fluorosis presents great variability worldwide. Its analysis is necessary as part of epidemiological surveillance Objective: To know the available literature on the prevalence of dental fluorosis among 12 years-old in relation to the community fluoridation method used. Methodology: Two researchers carried out a systematic review of the literature without time limits following the PRISMA guidelines, using the Pubmed, Cochrane, Scopus, BVS and Google Schoolar databases in English, Spanish, Portuguese and Italian. Results: 19 cross-sectional articles were included, 16 belonging to communities that use fluoridated water, one that use fluoridated salt and 2 that compare results between communities that use fluoridated water or salt. Conclusions: there is great variability in the reports of prevalence of dental fluorosis. Regardless of the community fluoridation method used, fluorosis lesions of mild severity are the most prevalent.

Fluoride in drinking groundwater and prevalence of fluorosis in children and adolescents: A systematic review / Fluoruro en el agua subterránea potable y prevalencia de fluorosis en niños y adolescentes: Una revisión sistemática

ABSTRACT Fluorosis is a worldwide public health problem. One of the factors related to it is the type of water consumed, such as groundwater. High fluoride concentration in groundwater may be explained by contamination from local industries. Since fluoride and arsenic are the main pollutants of groundwater, some studies correlate groundwater consumption with high prevalence of fluorosis Aim The aim of this study was to conduct a systematic review to determine whether children's risk of fluorosis is related to drinking groundwater Materials and Method The protocol for this systematic review was registered at the National Institute of Health Research Database (CRD42021227298). A comprehensive search was conducted to identify potentially relevant studies by exploring a range of electronic databases (Medline via PubMed, Scopus, Cochrane Library, Science Direct, Web of Science Core Collection, Medline via Ovid, Lilacs, Embase, and grey literature) Results A total 2189 articles were found. After reading titles and abstracts, 63 were selected for screening, and the final data was extracted from 15 articles Conclusion A relationship was identified between drinking fluoridated water from wells and the prevalence of fluorosis in individuals up to 18 years old. This is the first study to assess the issue systematically worldwide.

RESUMEN La fluorosis es un problema de salud pública a nivel mundial y el tipo de agua consumida es uno de los factores relacionados con ella, como el consumo de aguas subterráneas. La alta concentración de fluoruro en estas aguas puede justificarse por la contaminación por industrias locales y las características del suelo, donde algunos estudios correlacionan el consumo de aguas subterráneas con una alta prevalencia de fluorosis, ya que el fluoruro, junto con el arsénico, se consideran los principales contaminantes de estas aguas Objetivo El objetivo es realizar una revisión sistemática que relacione el riesgo de fluorosis en niños expuestos al consumo de agua procedente de pozos Materiales y Método El protocolo de esta revisión sistemática fue registrado en el National Institute of Health Research Database (CRD42021227298). Se realizó una búsqueda bibliográfica de estudios primarios explorando diversas bases de datos electrónicas (Medline vía PubMed, Scopus, Cochrane Library, Science Direct, Web of Science Core Collection, Medline vía Ovid, Lilacs, Embase y literatura gris) Resultados Se encontraron 2189 artículos, tras la lectura de títulos y resúmenes se seleccionaron 63 referencias para examinar y, finalmente, se extrajeron los datos de 15 artículos Conclusiones Se identificó una relación entre el consumo de agua fluorada de pozo y la prevalencia de fluorosis en individuos de hasta 18 años, siendo este estudio el primero en evaluarlo sistemáticamente a nivel mundial.

Fluorosis dental en adolescentes de instituciones educativas de Lima, Perú / Dental fluorosis in adolescents from Educational Institutions in Lima, Peru

Introducción: La fluorosis dental es una patología endémica causada por la ingestión excesiva de fluoruros que pueden producir una alteración durante el desarrollo del esmalte, y es considerado un importante problema de salud pública porque afecta la salud bucal y sistémica de la población. Objetivo: Este estudio tuvo como idea principal determinar la frecuencia y los niveles de fluorosis dental en escolares de 12 a 15 años pertenecientes a dos instituciones educativas de Lima - Perú. Método: Se realizó un estudio descriptivo de tipo transversal, la muestra estuvo conformada por 252 estudiantes, entre 12 y 15 años de dos centros educativos de Lima. El muestreo fue por selección sistemática de elementos muestrales. La fluorosis dental se evalúo mediante el Índice de Dean. Para determinar la frecuencia y los niveles de fluorosis dental, se realizó un examen clínico bucal y se desarrolló un cuestionario validado previamente. Resultados: La frecuencia de fluorosis dental fue de 44,8% (n=113) afectando más a los varones en un 27,39% (n=69) y a los adolescentes de 13 años (15,1%). En relación con los niveles de fluorosis, predominó el tipo "muy leve" (34,9%). También se encontró una asociación entre la presencia y el nivel de fluorosis con el número de aplicaciones de flúor (p<0,05). Además, se dijo que el índice comunitario de fluorosis de Dean fue de 0,43. Conclusiones: En la población escolar evaluada, la frecuencia de fluorosis fue de 44,8% y el nivel predominante de fluorosis fue muy leve. Además, el índice comunitario fue de 0,43, el cual mostró un nivel límite de importancia para la salud pública. Por lo que se puede considerar que el número de aplicaciones tópicas de flúor recibido por la población sin una planificación adecuada se podría convertir en un factor de riesgo para causar fluorosis dental.

Introduction: Dental fluorosis is an endemic pathology caused by the excessive ingestion of fluorides that can produce an alteration during the development of the enamel and is considered an important public health problema because it affects the oral and systemic health of the population. Objective: The objective of this study was to determine the frequency and levels of dental fluorosis in school children between 12 and 15 years of age belonging to two educational institutions in Lima, Peru. Method: A descriptive cross-sectional study was carried out, the sample consisted of 252 students between 12 and 15 years of age from two educational centers in Lima. Sampling was by systematic selection of sample elements. Dental fluorosis was evaluated using the Dean Index. To determine the frequency and levels of dental fluorosis a clinical oral examination was carried out and a previously validated questionnaire was developed. Results: The frequency of dental fluorosis was 44.8% (n=113) affecting more males by 27.39% (n=69) and adolescents aged 13 years (15.1%). In relation to the levels of fluorosis, the "very mild" type predominated (34.9%). An association was also found between the presence and level of fluorosis with the number of fluoride applications (p<0.05). In addition, Dean's community fluorosis index was reported to be 0.43. Conclusions: In the school population evaluated, the frequency of fluorosis was 44.8% and the predominant level of fluorosis was very mild. In addition, the community index was 0.43, which indicated a borderline level of public health importance. Therefore, it can be considered that the number of topical fluoride applications received by the population without adequate planning could become a risk factor for causing dental fluorosis.

Bond strength comparison among 10-MDP-containing and non-10-MDP-Containing adhesives in different degrees of dental fluorosis / Comparación de fuerza de unión entre adhesivos que contienen y no contienen 10-MDP en diferentes grados de fluorosis dental

Dental fluorosis can cause changes in the enamel surface, conditioning its functionality and esthetics. The application of dental adhesives is a treatment option; however, their use on fluorotic teeth can result in limitations. The aim of this study was to compare the shear bond strength of two different adhesives, one with 10-MDP and one without 10-MDP, in different degrees of dental fluorosis.This is an in vitro study on dental enamel samples, a total of 180 samples with the inclusion criteria were treated, randomly divided into two groups of 90, according to the type of dental adhesive, where each group was again divided into three groups of 30 samples, representing different degrees of dental fluorosis according to the Thylstrup-Fejerskov index (Group I: TF1 and TF2; Group II: TF3; Group III: TF4). Normality tests, two-factor ANOVA, and post-hoc tests were used to determine differences between the groups, with a significance level of 95%. As results, a statistically significant difference was shown between the use of dental adhesive with 10-MDP and the three groups of dental fluorosis (p=0.011), in addition, a Tukey post-hoc test on the groups treated with 10-MDP adhesive revealed a statistically significant difference between group I versus group II, and group I versus group III, (p=<0.05). It is concluded that the use of adhesive systems with 10-MDP presents a better shear bond strength on enamel with dental fluorosis grades I and II in the Thylstrup-Fejerskov index.

La fluorosis dental puede ocasionar cambios en la superficie del esmalte, condicionando su funcionalidad y estética, la aplicación de adhesivos dentales es una opción de tratamiento, sin embargo, su uso en dientes fluoroticos puede resultar en limitaciones. El objetivo de este estudio consistió en comparar la fuerza de adhesión a la cizalladura de dos diferentes adhesivos, uno con 10-MDP y otro sin 10-MDP, en diferentes grados de fluorosis dental. Se trata de un estudio in vitro en muestras de esmalte dental, un total de 180 muestras con los criterios de inclusión fueron tratadas, aleatoriamente divididas en dos grupos de 90, de acuerdo al tipo de adhesivo dental, donde cada grupo fue dividido nuevamente en tres grupos de 30 muestras, representando diferentes grados de fluorosis dental según el índice de Thylstrup- Fejerskov (Grupo I: TF1 y TF2; Grupo II: TF3; Grupo III: TF4). Para determinar diferencias entre los grupos se utilizaron pruebas de normalidad, ANOVA de dos factores, y pruebas post-hoc, con un nivel de significancia de 95%. Como resultados, se mostró una diferencia estadísticamente significativa entre el uso de adhesivo dental con 10- MDP y los tres grupos de fluorosis dental (p=0.011), además, una prueba post hoc de Tukey sobre los grupos tratados con adhesivo 10-MDP revelaron una diferencia estadísticamente significativa entre el grupo I frente al grupo II, y el grupo I frente al grupo III, (p=<0.05) Se concluye que el uso de sistemas adhesivos con 10-MDP presentan una mejor resistencia de adhesión al cizallamiento en esmalte con grados de fluorosis dental I y II en el índice de Thylstrup-Fejerskov

Fluorosis dental en la primera infancia: estado del arte

La fluorosis dental se caracteriza por una hipomineralización de la estructura dental causada por ingesta excesiva de flúor sistémico. En la dentición decidua, su diagnóstico precoz es importante, dado que será un predictor para la aparición de lesiones en la dentición permanente. El objetivo de esta revisión fue describir la evidencia científica sobre la fluorosis dental en dentición decidua reportando su etiología y factores relacionados, prevalencia, diagnóstico y tratamiento. Se realizaron búsquedas electrónicas en las bases de datos Pub-Med/Medline, EbscoHost y ScienceDirect (noviembre/2020), utilizando las palabras clave "dental fluorosis", "deciduous teeth", "primary tooth", "primary teeth". El desarrollo de fluorosis dental en dentición decidua se relacionó con la ingesta de múltiples fuentes de flúor principalmente, agua potable, alimentos de la dieta, fórmulas infantiles, suplementos y uso de dentífricos fluorados en dosis inadecuadas. Algunos factores prenatales, como vivir en terrenos montañosos o de gran altitud y habitar en lugares cercanos a minas de combustión de carbón, también fueron asociados. La prevalencia de fluorosis dental reportada en los estudios varió entre 6,2 y 96,6 %, dependiendo principalmente de la concentración de flúor en agua potable. Para el diagnóstico de la fluorosis dental en la dentición decidua se deben considerar características como la localización, aspecto, extensión y color de la lesión, realizando diagnóstico diferencial con otro tipo de defectos en esmalte y dentina. Así mismo, el tratamiento de las lesiones dependerá de la severidad del defecto y condiciones individuales del paciente.

Dental fluorosis is characterized by a hypomineralization of the tooth structure caused by excessive intake of systemic fluoride. In the deciduous dentition, its early diagnosis is important since it will be a predictor for the appearance of lesions in the permanent dentition. The objective of this review was to describe the scientific evidence on dental fluorosis in deciduous dentition, reporting its etiology and related factors, prevalence, diagnosis and treatment. Electronic searches were conducted PubMed / Medline, EbscoHost and ScienceDirect (November / 2020) databases, using the keywords "dental fluorosis", "deciduous teeth", "primary tooth", "primary teeth". The development of Dental fluorosis in deciduous dentition was related to the intake of multiple sources of fluoride mainly; drinking water, diet foods, infant formulas, supplements and the use of luoridated toothpastes in inadequate doses. Some prenatal factors such as living in mountainous or high altitude terrain and living in places near coal-burning mines were also associated. The prevalence of dental fluorosis in early childhood reported in the studies varied between 6.2% and 96.6%, depending mainly on the concentration of fluoride in drinking water. For the diagnosis of dental fluorosis in the deciduous dentition, characteristics such as the location, appearance, extension and color of the lesion must be considered, making a differential diagnosis with other types of enamel and dentin defects. Evenly, the treatment of lesions will depend on the severity defects and individual patient conditions.

Susceptibility of fluorotic enamel to dental erosion-abrasion

Abstract Dental hard tissue conditions can be of pre- or post-eruptive nature, such as enamel fluorosis and erosive tooth wear (ETW), respectively. Dental enamel fluorosis is caused by the chronic and excessive intake of fluoride during enamel development, leading to increased fluoride concentration and increased porosity. ETW has become a common clinical condition and often impairs dental function and aesthetics. This in vitro study tested the hypothesis that fluorotic enamel presents different susceptibility to dental erosion-abrasion. It consisted of a 3×3×2 factorial design, considering a) fluorosis severity: sound (TF0), mild (TF1-2), moderate (TF3-4); b) abrasive challenge: low, medium, and high; and c) erosive challenge: yes or no. A total of 144 human teeth were selected according to the three fluorosis severity levels (n=48), and subdivided into six groups (n = 8) generated by the association of the different erosive and abrasive challenges. Enamel blocks (4×4 mm) were prepared from each tooth and their natural enamel surfaces subjected to an erosion-abrasion cycling model. After cycling, the depth of the lesions in enamel was assessed by profilometry. ANOVA showed that the three-way and two-way interactions among the factors were not significant (p > 0.20). Enamel fluorosis level (p=0.638) and abrasion level (p = 0.390) had no significant effect on lesion depth. Acid exposure caused significantly more enamel surface loss than water (p < 0.001). Considering the limitations of this in vitro study, fluorosis did not affect the susceptibility of enamel to dental erosion-abrasion.

Fluoride in Mozambique: retrospective study / Flúor em Moçambique: estudo retrospectivo

ABSTRACT Objective: The study aims to analyse the fluoride concentration in the water supply of the capital of each province of Mozambique, 2019 and compare with previous data 1978 and 2008. Methods: The water supply in cities of Mozambique were analysed in 1978, 2008 and 2019 and water from Tete's River in 1978 and 2019. The fluoride concentration of the water samples was determined in duplicate, using the ion-sensitive electrode (Orion 9609), coupled to a potentiometer (Procyon, model 720), adopting a significance level of 5%. Results: The average fluoride concentration found in the years 1978, 2008 and 2019 was 0.31, 0.33 and 0.14 mg F/L, respectively. The fluoride concentrations collected from household taps in 1978, 2008 and 2019 were: Cabo Delgado/Pemba (0.62, 0.28 and 0.07 mg F/L), Niassa/Lichinga (0.18, 0.98 and 0.07 mg F/L), Nampula/Nampula (0.18, 0.01 and 0.06 mg F/L), Zambézia/Quelimane (0.81, 0.37 and 0.15 mg F/L), Tete/Tete (1.00, 0.97 and 0 .46 mg F/L), Sofala/Beira (0.00, 0.01 and 0.10mg F/L), Manica/Chimoio (0.04, 0.01 and 0.07 mg F/L), Inhambane/Inhambane (0.00, 0.05 and 0.19 mg F/L), Gaza/Xai-Xai (0.01, 0.06 and 0.06 mg F/L) and Maputo (0.23, 0.36 and 0.23 mg F/L), respectively. In the waters of the Zambeze River was 5.5 mg F/L in 1978 and 0.12 mg F/L in 2019. There was no significant change between the fluoride concentrations in the water collected from the taps during the periods studied (p=0.83), however there was a significant difference in the water collected from the river (p<0.05). Conclusion: Tete' River showed a significant reduction in fluoride concentration, and in the piped water collected in all municipalities, the fluoride content was below optimum.

RESUMO Objetivo: O estudo visa analisar a concentração de flúor no abastecimento de água da capital de cada província de Moçambique, 2019 e comparar com dados anteriores de 1978 e 2008. Métodos: A água de abastecimento das cidades de Moçambique foi analisada em 1978, 2008 e 2019 e a água do Rio Tete em 1978 e 2019. A concentração de flúor das amostras de água foi determinada em duplicata, utilizando o eletrodo íon-sensível (Orion 9609), acoplado a um potenciômetro (Procyon, modelo 720), adotando-se nível de significância de 5%. Resultados: A concentração média de flúor encontrada nos anos de 1978, 2008 e 2019 foi de 0,31, 0,33 e 0,14 mg F/L, respectivamente. As concentrações de flúor recolhidas nas torneiras das casas em 1978, 2008 e 2019 foram: Cabo Delgado/Pemba (0,62, 0,28 e 0,07 mg F/L), Niassa/Lichinga (0,18, 0,98 e 0,07 mg F/L), Nampula/Nampula (0,18, 0,01 e 0,06 mg F/L), Zambézia /Quelimane (0,81, 0,37 e 0,15 mg F/L), Tete/Tete (1,00, 0,97 e 0,46 mg F/L), Sofala/Beira (0,00, 0,01 e 0,10 mg F/L), Manica/Chimoio (0,04, 0,01 e 0,07 mg F/L), Inhambane/Inhambane (0,00 , 0,05 e 0,19 mg F/L), Gaza/Xai-Xai (0,01, 0,06 e 0,06 mg F/L) e Maputo (0,23, 0,36 e 0,23 mg F/L), respectivamente. Nas águas do rio Zambeze foi de 5,5 mg F/L em 1978 e 0,12 mg F/L em 2019. Não houve alteração significativa entre as concentrações de flúor na água coletada das torneiras durante os períodos estudados (p=0,83), porém houve diferença significativa na água captada no Rio (p<0,05). Conclusão: O Rio Tete apresentou redução significativa na concentração de flúor, e na água das torneiras coletada em todas as cidades, o teor de flúor estava abaixo do ideal.

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

Fluorose dentária e determinantes sociais da saúde: Revisão integrativa / Dental fluorosis and social determinants of health: Integrative review / Fluorosis dental y determinantes sociales de la salud: revisión integradora

Objetivo: verificar o desenvolvimento da fluorose dentária e sua relação com os Determinantes Sociais da Saúde (DSS) através de uma revisão integrativa. Método: trata-se de uma revisão integrativa de estudos que abordam os aspectos dos DSS e sua relação com a fluorose dentária. A coleta de dados foi realizada entre o período de agosto de 2020 a abril de 2021. Resultados: dos estudos selecionados de língua portuguesa e inglesa observou-se que o Fluorose Dentária é um problema de saúde pública, de âmbito mundial. Conclusão: Assim, é oportuno pensar que a fluorose dentária pode ser influenciada pelo meio ao qual o indivíduo se insere, suas condições sociais, econômicas, psicológicas e comportamentais devem ser consideradas, conforme o olhar dos DSS.

Objective: to verify the development of dental fluorosis and its relationship with the Social Determinants of Health (SDH) through an integrative review. Method: this is an integrative review of studies that address aspects of DSS and its relationship with dental fluorosis. Data collection was carried out between August 2020 and April 2021. Results: from selected studies in Portuguese and English, it was observed that Dental Fluorosis is a public health problem, worldwide. Conclusion: Thus, it is opportune to think that dental fluorosis can be influenced by the environment in which the individual is inserted, their social, economic, psychological and behavioral conditions must be considered, according to the perspective of the DSS.

Objetivo: verificar el desarrollo de la fluorosis dental y su relación con los determinantes sociales de la salud (DE) a través de una revisión integradora. Método: se trata de una revisión integradora de estudios que abordan los aspectos de las SD y su relación con la fluorosis dental. Los datos fueron recolectados entre agosto de 2020 y abril de 2021. Resultados: a partir de los estudios seleccionados de portugués e inglés, se observó que la fluorosis dental es un problema de salud pública en todo el mundo. Conclusión: Por lo tanto, es oportuno pensar que la fluorosis dental puede estar influenciada por el entorno al que se incluye al individuo, se deben considerar sus condiciones sociales, económicas, psicológicas y de comportamiento, de acuerdo con la mirada del SSD.

Influence of dietary composition of residents in endemic fluorosis area on the prevalence of skeletal fluorosis / 中华地方病学杂志

Objective:To analyze the relationship between dietary composition of residents in endemic fluorosis areas and skeletal fluorosis.Methods:A case-control study was used to analyze the difference of dietary composition between patients with skeletal fluorosis (case group) and residents without skeletal fluorosis (control group). In August 2019, taking the drinking water-borne endemic fluorosis area in Wenshui County, Lvliang City, Shanxi Province as the survey site, a cluster sampling method was adopted to select local residents aged over 18 years old, and a questionnaire survey was conducted by face-to-face interview. The survey contents included gender, age and consumption frequency of various foods. Binary logistic regression was used to analyze the relationship between food consumption frequency and skeletal fluorosis. The diagnosis of skeletal fluorosis was made by using portable digital radiography (DR) to take X-ray films of forearm and lower leg, combining with clinical signs, and according to the Diagnostic Standard for Endemic Skeletal Fluorosis (WS/T 192-2008) to determine.Results:A total of 1 061 subjects were included in this study, including 376 in the case group and 685 in the control group. The age composition of patients in the case group (≤60, > 60 years old: 162, 214 cases) was significantly different from that in the control group (≤60, > 60 years old: 423, 261 cases, χ 2 = 34.52, P < 0.001). There was no statistically significant difference in gender ratio (χ 2 = 1.37, P = 0.251). The proportion of patients in the case group who ate meat and eggs > 1 time/week was lower than that in the control group (χ 2 = 8.06, 5.46, P < 0.05), the proportion of patients who ate milk > 1 time/week was higher than that in the control group (χ 2 = 4.01, P = 0.046), and the proportion of patients who ate seafood ≥1 time/week was lower than that in the control group (χ 2 = 4.16, P = 0.046). The results of binary logistic regression analysis showed that after adjusting for age, sex, and urinary fluoride, the frequency of eating meat, eggs or milk > 1 time/week and the frequency of eating seafood ≥1 time/week were not related to the risk of skeletal fluorosis ( P > 0.05); however, in the group ≤60 years old, the frequency of eating eggs > 1 time/week was associated with the risk of skeletal fluorosis [odds ratio ( OR) = 0.59, 95% confidence interval ( CI): 0.39, 0.88]. Conclusions:The consumption frequency of meat, milk, eggs and seafood is significantly different between the skeletal fluorosis patients and the control people. In the population ≤60 years old, consumption frequency of eggs > 1 time/week may reduce the risk of skeletal fluorosis.

Evaluation on the effect of prevention and control of coal-burning-borne endemic fluorosis in Sichuan Province from 2018 to 2021 / 中华地方病学杂志

Objective:To evaluate the effectiveness of prevention and control of coal-burning-borne endemic fluorosis in Sichuan Province, and to provide basis for further development of targeted prevention and control measures.Methods:According to the requirements of the Implementation Plan for the Elimination and Evaluation of Coal-burning-borne Endemic Fluorosis in Sichuan Province, from 2018 to 2021, the assessment of the elimination of coal-burning-borne endemic fluorosis was carried out in all the endemic fluorosis villages of 23 counties (cities, districts) in Sichuan Province. In each village, 30 households were selected to be investigated the use of improved stoves, the drying of corn and pepper for human consumption, and the prevalence of dental fluorosis among all children aged 8 - 12 years old in the village.Results:A total of 222 242 households were surveyed in 1 640 villages, 196 towns, 23 counties (cities, districts) in Sichuan Province. Among them, the rate of qualified improved stoves was 99.99% (222 238/222 242), the correct use rate of qualified improved stoves was 99.90% (212 026/222 238), and the correct drying rate of corn and pepper for human consumption was 99.96% (212 630/212 721). A total of 135 125 children aged 8 to 12 years old were examined, and 5 927 cases of dental fluorosis were detected. The prevalence of dental fluorosis in children was 4.39%. The grading of dental fluorosis was mainly very mild and mild, which were 2.71% (3 656/135 125) and 1.32% (1 783/135 125), respectively. In the county-level self-assessment of 1 640 villages, 1 621 villages had reached the elimination standard, with the elimination rate of 98.84%. Taking counties as a unit, the elimination rate of diseased villages ranged from 96.69% to 100.00%, and 23 diseased counties (cities, districts) had reached the elimination standard. In the provincial-level review results of 174 villages with endemic fluorosis, 174 diseased villages had reached the elimination standard, with the consistency rate of 98.85% (172/174) with the county-level self-assessment results. Among them, except for Gulin County, the consistency rate of self-assessment results was 7/9, the consistency rate of other counties (cities, districts) was 100.00%.Conclusions:The prevention and control of coal-burning-borne endemic fluorosis in Sichuan Province has achieved remarkable results, and all the diseased counties (cities, districts) have reached the elimination standard. In the future, we should continue to take active prevention and control measures to ensure that the elimination status is maintained.

Monitoring results of coal-burning-borne endemic fluorosis in Yunnan Province in 2020 / 中华地方病学杂志

Objective:To learn about the current situation of prevention and control of coal-burning-borne endemic fluorosis (coal burning fluorosis for short) in Yunnan Province, and comprehensively evaluate the implementation effect of prevention and control measures.Methods:From August to November 2020, according to the requirements of the Monitoring Program of Yunnan Province for Coal-burning-borne Endemic Fluorosis (2019 edition), monitoring was carried out in all natural villages in the disease areas of 13 counties (cities and districts, hereinafter referred to as counties) of the province, and 30 households were selected from each natural village to monitor the use of stoves and the formation of related healthy living behaviors. At the same time, children aged 8 - 12 years in the natural villages in the disease areas were examined for the prevalence of dental fluorosis. The evaluation for control and elimination of disease areas was carried out in accordance with the Evaluation Approach for Control and Elimination of Priority Endemic Diseases (2019 edition).Results:A total of 392 244 households were investigated, and the rates of qualified improved stoves, the correct utilization of qualified improved stoves and correct drying of corn and pepper were 99.42% (389 982/392 244), 99.70% (388 796/389 982) and 99.07% (388 579/392 244), respectively. A total of 227 057 children aged 8 - 12 years were examined, 9 413 children of dental fluorosis were detected, the detection rate of dental fluorosis was 4.15%, the dental fluorosis index was 0.10, and the prevalence intensity was negative. Taking the county as a unit, except Fuyuan and Zhenxiong, which reached the control standard of the disease area, the remaining 11 counties reached the elimination standard.Conclusion:The prevention and control measures on coal burning fluorosis are implemented well in Yunnan Province and healthy lifestyle has gradually taken shape, with the overall condition of the disease reduced.

Analysis of influencing factors of dental fluorosis in children based on logistic regression and classification tree model / 中华地方病学杂志

Objective:To analyze the influencing factors of dental fluorosis of children in the drinking-water-borne endemic fluorosis (referred to as drinking-water-borne fluorosis) areas with qualified drinking water.Methods:In 2020 and 2021, the cluster sampling method was used to select the children aged 8 to 12 years old from the drinking-water-borne fluorisis areas with qualified drinking water in Tianjin City for water and urine fluoride detection, dental fluorosis examination and questionnaire survey, and logistic regression and classification tree model were used to analyze the influencing factors of dental fluorosis in children.Results:A total of 3 795 cases children aged 8 to 12 years old were investigated, and 1 001 cases of dental fluorosis were detected, and the detection rate of dental fluorosis was 26.38% (1 001/3 795). The results of logistic analysis showed that age [odds ratio ( OR) = 1.193, 95% confidence interval ( CI): 1.115 - 1.277], high urinary fluoride (1.84 - 19.40 mg/L, OR = 1.510, 95% CI: 1.169 - 1.952) and the number of permanent residents at home ≥6 ( OR = 1.377, 95% CI: 1.090 - 1.739) were risk factors of dental fluorosis in children; and the mother's with higher education level (college degree or above, OR = 0.664, 95% CI: 0.441 - 0.999), the years of water improvement ≥5 years (5 - < 10 years, OR = 0.193, 95% CI: 0.157 - 0.238; ≥10 years, OR = 0.254, 95% CI: 0.193 - 0.333) were protective factors of dental fluorosis in children. The results of classification tree model analysis showed that the years of water improvement contributed the most to the prevalence of dental fluorosis among children in the drinking-water-borne fluorisis areas with qualified drinking water, followed by age, number of permanent residents at home and urinary fluoride. The area under the receiver operating characteristic curve (AUC) of logistic regression model and classification tree model were 0.730 (95% CI: 0.711 - 0.748) and 0.721 (95% CI: 0.702 - 0.739), respectively, with good fitting effect. Conclusion:The detection rate of children's dental fluorosis in the drinking-water-borne fluorosis areas with qualified drinking water is mainly related to the years of water improvement, age, the number of permanent residents at home and urinary fluoride.