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1.
Int J Paleopathol ; 26: 48-60, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31228793

RESUMO

OBJECTIVE: To carefully assess skeletal lesions in close environment context in order to evaluate whether skeletal fluorosis was present in individuals living in the prehistoric Midwest, USA. MATERIALS: Skeletal remains from minimally 117 individuals recovered from the Ray Site, located in western Illinois (USA) and dated to the Middle/early Late Woodland periods (50 BC-AD 400). METHODS: Macroscopic evaluation of all recovered skeletal elements. RESULTS: Eight individuals display a constellation of abnormal bony changes, including osteosclerosis, a high frequency of fractures, and dental abnormalities. CONCLUSIONS: The osteosclerotic changes along with the naturally high fluoride content of west central Illinois soil and water suggests the presence of skeletal fluorosis. SIGNIFICANCE: This is the first report of skeletal fluorosis from archaeologically recovered human remains from North America. LIMITATIONS: The ambiguous nature of the skeletal changes associated with fluorosis, especially in the less severe stages of the disease, renders determination of the etiology difficult. SUGGESTIONS FOR FURTHER RESEARCH: The continuation of paleopathological investigations of fluoride toxicity within archaeological communities recovered from this region with emphasis on the incorporation of biomedical and environmental data. Furthermore, complementary analyses of the chemical composition and the histological presentation of the skeletons could provide support for this diagnosis.


Assuntos
Doenças Ósseas/etiologia , Doenças Ósseas/história , Exposição Ambiental/história , Intoxicação por Flúor/história , Doenças Ósseas/patologia , Criança , Feminino , Intoxicação por Flúor/patologia , Fluorose Dentária/história , Fluorose Dentária/patologia , História Antiga , Humanos , Illinois , Masculino , Pessoa de Meia-Idade , Paleopatologia
2.
Indian J Med Res ; 149(3): 364-368, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-31249201

RESUMO

Background & objectives: : There is a paucity of information on association between dental fluorosis, osteoporosis and periodontitis. The aim of this pilot study was to evaluate oestrogen receptor (ER). Rsa 1: gene polymorphism in osteoporosis periodontitis patients with and without dental fluorosis. Methods: : Twenty one primary osteoporotic patients suffering from periodontitis with dental fluorosis and 20 primary osteoporotic patients suffering from periodontitis without dental fluorosis participated in this study. Periodontitis was diagnosed based on age, gender T-scores using clinical parameters such as plaque scores, gingival bleeding scores and probing pocket depth, clinical attachment level (CAL) and severity of dental fluorosis. DNA was genotyped at the RsaI RFLP (in exon 5) inside the ER gene to study ER Rsa I gene polymorphism in osteoporosis periodontitis patients with and without dental fluorosis. Results: : Patients with dental fluorosis had higher degree of osteoporosis than those without fluorosis. CAL was significantly higher (P <0.05) in those with dental fluorosis compared with those without. Rr heterozygote (21.95%) was observed in patients without fluorosis whereas RR mutant homozygote was absent in both the groups. Rr wild homozygote type was seen more in the patients with fluorosis (51.21%). Significant differences were found in distribution of these genotypes between patients with and without dental fluorosis. Interpretation & conclusions: : This preliminary study showed the presence of ER I gene polymorphism in osteoporosis periodontitis patients without dental fluorosis. Further studies with large sample size are needed to confirm the association shown in this preliminary study.


Assuntos
Receptor alfa de Estrogênio/genética , Fluorose Dentária/genética , Osteoporose/genética , Periodontite/genética , Adulto , Idoso , Desoxirribonucleases de Sítio Específico do Tipo II/genética , Feminino , Fluorose Dentária/epidemiologia , Fluorose Dentária/patologia , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Osteoporose/epidemiologia , Osteoporose/patologia , Periodontite/epidemiologia , Periodontite/patologia
3.
Methods Mol Biol ; 1922: 335-340, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30838588

RESUMO

Chronic fluoride overexposure can cause dental fluorosis. Dental fluorosis is characterized by porous and soft enamel that is vulnerable to erosion and decay. Animal models often contribute to clinical applications by addressing pathogenic questions of disease. To study dental fluorosis, rodent models have been employed because rodent incisors erupt continuously and every stage of enamel development is present along the length of the rodent incisor. Here we present a protocol to induce dental fluorosis in mouse and rat and describe the procedure for extraction of stage specific enamel organ from rat mandibular incisors.


Assuntos
Modelos Animais de Doenças , Órgão do Esmalte/patologia , Fluorose Dentária/patologia , Incisivo/patologia , Animais , Dissecação/métodos , Camundongos Endogâmicos C57BL , Ratos Sprague-Dawley
4.
Environ Int ; 127: 70-77, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30909095

RESUMO

BACKGROUND: The alteration of mitochondrial DNA (mtDNA) content contributes to many diseases, however, little is known about its effect on the prevalence of dental fluorosis (DF). OBJECTIVES: We conducted a cross-sectional study to investigate the association of low-to-moderate fluoride exposure with relative mtDNA levels in relation to DF in children. METHODS: We recruited 616 resident children, aged 7-13 years, randomly from low-to-moderate fluoride areas in Tianjin, China. We measured the fluoride concentrations in drinking water and urine using the national standardized ion selective electrode method, and determined the relative levels of mtDNA using a quantitative real-time polymerase chain reaction assay. The association among fluoride exposure, relative mtDNA levels, and the prevalence of DF were examined using multivariable linear and logistic regression models. We also performed stratified and mediation analyses. RESULTS: The relative mtDNA levels of participants in the DF group were significantly lower than in the non-DF group (0.95 ±â€¯0.44 vs. 1.12 ±â€¯0.45, P < 0.001). In the adjusted models, we found that a 1 mg/L increment in water fluoride concentration was associated with a 0.10-unit decrease in circulating relative mtDNA levels (95% CI: -0.14, -0.06) and a 2.85-fold increase (95% CI: 2.01, 3.92) in moderate DF prevalence. A 1 mg/L increment in urinary fluoride level was associated with a 0.12-unit decrease in circulating relative mtDNA levels (95% CI: -0.14, -0.09) and a 1.85-fold increase (95% CI: 1.39, 2.39) in moderate DF prevalence. Stratified analysis indicated a weaker positive association of DF prevalence with fluoride exposure, while a stronger inverse relationship with relative mtDNA levels in boys than in girls. Assuming causality, we estimated that circulating mtDNA levels mediated 13.0% (95% CI: 5.2, 28.7%) and 9.6% (95% CI: 4.7, 18.5%) of the estimated effect of a 1 mg/L increment in water fluoride and urinary fluoride on prevalence of moderate DF, respectively. CONCLUSIONS: Gender potentially modifies the associations of DF prevalence with relative mtDNA levels and low-to-moderate fluoride exposure. The reduced circulating mtDNA levels may partly mediate the elevated prevalence of moderate DF in children under such exposure.


Assuntos
DNA Mitocondrial/sangue , Fluoretos/toxicidade , Fluorose Dentária/epidemiologia , Adolescente , Criança , China/epidemiologia , Estudos Transversais , Feminino , Fluoretos/química , Fluorose Dentária/genética , Fluorose Dentária/patologia , Humanos , Masculino , Prevalência , Água/química
5.
Ceylon Med J ; 63(3): 139-142, 2018 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-30415519

RESUMO

Background: The WHO recommended safe upper limit for fluoride in drinking water is 1.5 mg/l. Groundwater sources in many parts of Sri Lanka often exceed this limit. The high fluoride content of groundwater and high environmental temperatures in Vavuniya District predispose to pre-skeletal fluorosis and skeletal fluorosis in adults. Objectives: To identify residents of Vavuniya District with clinical features of pre-skeletal and skeletal fluorosis; to describe their clinical, biochemical and radiographic features; to determine the fluoride content of blood and urine in individuals with established diagnoses, and of their drinking water. Methods: In 98 volunteers we detected 60 with clinical features of pre-skeletal and skeletal fluorosis. Clinical examination, biochemical and radiographic investigations were performed. Forty four with confounding factors were excluded. The balance 16 had radiographic investigation for fluoride bone disease, and assessment of clinical features for pre-skeletal fluorosis. The radiographic criteria of skeletal fluorosis were trabecular haziness, osteosclerosis, osteophytes, cortical thickening and ligamentous or muscle attachment ossification. All 16 had "spot" samples of 15 ml of venous blood taken for biochemical tests and fluoride estimation; and 30 ml of urine, and water from 16 dug wells for fluoride. Results: The 16 selected (11 males) had BMI between 20.6 and 31.9 kg/m2, and were between 22 and 84 years (x̅ = 59.9 + 20.4). They used water from domestic dug wells for drinking. All had adequate renal function. All serum and urine samples had raised fluoride levels way above the reference ranges for serum (0.02 ­ 0.18 mg/l) and urine (0.6 ­ 2.0 mg/l). The 16 water samples showed a mean fluoride content of 2.90 +0.93 mg/l. Interpretation: In a cohort of 60 individuals in Vavuniya with symptoms suggestive of skeletal fluoride toxicity, 6 had skeletal fluorosis, 10 had pre-skeletal fluorosis, and groundwater sources had fluoride levels much higher than WHO recommended upper limit for drinking water. Residents in Vavuniya are predisposed to pre-skeletal and skeletal fluorosis. All 16 had been misdiagnosed as various types of arthritis.


Assuntos
Doenças Ósseas/patologia , Água Potável/química , Fluoretos/análise , Fluorose Dentária/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Doenças Ósseas/etiologia , Água Potável/efeitos adversos , Feminino , Fluoretos/toxicidade , Fluorose Dentária/etiologia , Humanos , Masculino , Pessoa de Meia-Idade , Sri Lanka , Abastecimento de Água , Adulto Jovem
6.
J Dent ; 74: 107-112, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29800639

RESUMO

OBJECTIVE: This retrospective in-vitro study investigated tooth age effect on dental hard-tissue conditions. METHODS: Unidentified extracted premolars (n = 1500) were collected and their individual age was estimated (10-100 (±10) years old (yo)) using established dental forensic methods Dental caries, fluorosis and tooth wear (TW) were assessed using the International Caries Detection and Assessment System (ICDAS; 0-5 for crown and 0-2 for root), Thylstrup-Fejerskov (TFI; 0-9) and Basic Erosive Wear Examination (BEWE; 0-3) indices, respectively. Staining and color were assessed using the modified-Lobene (MLI) (0-3) and VITA shade (B1-C4) indices, respectively. Relationships between indices and age were tested using regression models. RESULTS: Starting at age ∼10yo, presence of caries increased from 35% to 90% at ∼50yo (coronal), and from 0% to 35% at ∼80yo (root). Caries severity increased from ICDAS 0.5 to 2 at ∼40yo and from ICDAS 0 to 0.5 at ∼60yo for coronal and root caries, respectively. Presence of TW increased from 25% (occlusal) and 15% (smooth-surfaces) to 100% at ∼80yo. TW severity increased from BEWE 0.5 to 2 at ∼50yo (occlusal) and ∼0.3 to 1.5 at ∼50yo (smooth-surfaces). Percentage and severity of fluorosis decreased from 70% to 10% at ∼80yo, and from TFI 1 to 0 at ∼90yo, respectively. Percentage of extrinsic staining increased from 0% to 85% at ∼80yo and its severity increased from MLI 0 to 2 at ∼70yo. Color changed from A3 to B3 at ∼50yo (crown), and from C2 to A4 at ∼85yo (root). CONCLUSIONS: Aging is proportionally related to the severity of caries, TW, staining, and inversely to dental fluorosis. Teeth become darker with age.


Assuntos
Cárie Dentária/patologia , Esmalte Dentário/patologia , Dentina/patologia , Fluorose Dentária/patologia , Desgaste dos Dentes/patologia , Adolescente , Adulto , Determinação da Idade pelos Dentes/métodos , Idoso , Idoso de 80 Anos ou mais , Envelhecimento , Dente Pré-Molar , Criança , Cor , Feminino , Odontologia Legal , Dureza , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Coroa do Dente , Odontopatias , Adulto Jovem
7.
J Histochem Cytochem ; 66(9): 663-671, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29676651

RESUMO

The clinical and pathological features of fluorosis are similar to amelogenesis imperfecta (AI) caused by FAM83H mutations, suggesting that excess fluoride could have effects on the expression of Fam83h. Our previous study found that Fam83h was downregulated by fluorosis induction in ameloblasts; the purpose of this study was to underline the importance of understanding the relationship between fluoride administration and Fam83h expression in vivo. A total of 80 healthy female adult Kunming mice were randomly divided into control group or F group that induced the clinical features of fluorosis. Immunohistochemical staining on sections of the embryo mandible regions was performed at different developmental stages. Mouse primary ameloblast-like cells of the two groups at E13.5, E15.5, and E18.5 were cultured and examined for the expression of Fam83h. The expression of Fam83h in the F group was significantly lower than that in the control group; however, Fam83h was observed clearly in the whole enamel organ in the control group. Our findings shed new light on the potential effects of Fam83h in fluorosis using a mouse model and revealed that high fluoride decreased the expression of Fam83h. This may be one of the reasons for the occurrence of fluorosis.


Assuntos
Fluorose Dentária/patologia , Dente Molar/patologia , Proteínas/análise , Ameloblastos/patologia , Amelogênese Imperfeita/patologia , Animais , Células Cultivadas , Feminino , Imuno-Histoquímica , Camundongos , Dente Molar/crescimento & desenvolvimento
8.
Int J Mol Med ; 39(5): 1155-1163, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28339032

RESUMO

Epidemiological investigations indicate that certain ingredients in tea bricks can antagonize the adverse effects of fluoride. Tea polyphenols (TPs), the most bioactive ingredient in tea bricks, have been demonstrated to be potent bone-supporting agents. ClC­7 is known to be crucial for osteoclast (OC) bone resorption. Thus, in this study, we investigated the potential protective effects of TPs against fluorosis using a mouse model and explored the underlying mechanisms with particular focus on ClC­7. A total of 40, healthy, 3­week­old male C57BL/6 mice were randomly divided into 4 groups (n=10/group) by weight as follows: distilled water (control group), 100 mg/l fluoridated water (F group), water containing 10 g/l TPs (TP group) and water containing 100 mg/l fluoride and 10 g/l TPs (F + TP group). After 15 weeks, and after the mice were sacrificed, the long bones were removed and bone marrow-derived macrophages were cultured ex vivo in order to perform several experiments. OCs were identified and counted by tartrate­resistant acid phosphatase (TRAP) staining. The consumption of fluoride resulted in severe fluorosis and in an impaired OC function [impaired bone resorption, and a low mRNA expression of nuclear factor of activated T-cells 1 (NFATc1), ATPase H+ transporting V0 subunit D2 (ATP6v0d2) and osteopetrosis­associated transmembrane protein 1 (Ostm1)]. In the F + TP group, fluorosis was attenuated and OC function was restored, but not the high bone fluoride content. Compared with the F group, mature OCs in the F + TP group expressed higher mRNA levels of ClC­7 and Ostm1; the transportation and retaining of Cl­ was improved, as shown by the fluorescence intensity experiment. On the whole, our findings indicate that TPs mitigate fluorosis in C57BL/6 mice by regulating OC bone resorption. Fluoride inhibits OC resorption by inhibiting ClC­7 and Ostm1, whereas TPs attenuate this inhibitory effect of fluoride.


Assuntos
Osso e Ossos/efeitos dos fármacos , Osso e Ossos/metabolismo , Fluorose Dentária/genética , Proteínas de Membrana/genética , Polifenóis/farmacologia , Chá/química , Animais , Biomarcadores , Peso Corporal/efeitos dos fármacos , Reabsorção Óssea/genética , Reabsorção Óssea/metabolismo , Osso e Ossos/patologia , Osso e Ossos/ultraestrutura , Modelos Animais de Doenças , Fluorose Dentária/metabolismo , Fluorose Dentária/patologia , Fluorose Dentária/prevenção & controle , Expressão Gênica , Homeostase , Imuno-Histoquímica , Masculino , Proteínas de Membrana/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Fatores de Transcrição NFATC/genética , Fatores de Transcrição NFATC/metabolismo , Osteoclastos/efeitos dos fármacos , Osteoclastos/metabolismo , Osteoclastos/ultraestrutura , Extratos Vegetais/farmacologia , Substâncias Protetoras/farmacologia
9.
Chem Biol Interact ; 261: 27-34, 2017 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-27871895

RESUMO

Fluoride is an environmental toxicant and induces dental fluorosis and oxidative stress. Lycopene (LYC) is an effective antioxidant that is reported to attenuate fluoride toxicity. To determine the effects of LYC on sodium fluoride (NaF) -induced teeth and ameloblasts toxicity, rats were treated with NaF (10 mg/kg) and/or LYC (10 mg/kg) by orally administration for 5 weeks; ameloblasts were treated with NaF (5 mM) and/or LYC (2 µM) for 6 h. We found that the concentrations of fluoride, malondialdehyde (MDA) and reactive oxygen species (ROS), gene expressions and activities of Caspase-9 and Caspase-3, and the gene expressions of Bax were significantly decreased, while the activities of superoxide dismutase (SOD) and glutathione peroxidase (GPX), the gene expression of Bcl-2 were significantly increased in the LYC + NaF-treated rats group; concentrations of MDA and ROS, gene expressions and activities of Caspase-9 and Caspase-3, and the gene expression of Bax, and ameloblasts apoptosis rate were significantly decreased, while the activities of SOD and GPX, the gene expression of Bcl-2 were significantly increased in the LYC + NaF-treated ameloblasts group. These results suggest that LYC significantly combated NaF-induced ameloblasts apoptosis and dental fluorosis by attenuation oxidative stress and down-regulation Caspase pathway.


Assuntos
Ameloblastos/patologia , Apoptose/efeitos dos fármacos , Carotenoides/farmacologia , Caspases/metabolismo , Fluorose Dentária/patologia , Estresse Oxidativo/efeitos dos fármacos , Substâncias Protetoras/farmacologia , Fluoreto de Sódio/toxicidade , Ameloblastos/efeitos dos fármacos , Ameloblastos/enzimologia , Animais , Caspases/genética , Regulação para Baixo/efeitos dos fármacos , Fluorose Dentária/enzimologia , Glutationa Peroxidase/metabolismo , Incisivo/efeitos dos fármacos , Licopeno , Masculino , Malondialdeído/metabolismo , Camundongos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos Sprague-Dawley , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/efeitos dos fármacos , Superóxido Dismutase/metabolismo , Proteína X Associada a bcl-2/genética , Proteína X Associada a bcl-2/metabolismo
10.
Indian J Med Res ; 144(1): 52-57, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27834326

RESUMO

BACKGROUND & OBJECTIVES: The Indian Council of Medical Research (ICMR) formulated a Task Force on dental fluorosis and recommended the subgroup to develop a simplified index for identification and grading of dental fluorosis to be used by the health workers. This study was conducted to pre-test the 'ICMR Index for Dental Fluorosis' in the field to check its reliability and reproducibility. METHODS: A total of 600 photographs were taken, 150 in each grade of fluorosis by screening 14-17 yr school children from eight schools of Hisar (Haryana) and South west Delhi. Eighty photographs were finalized (20 in each grade) before calibration to be used for training of field workers. Calibration exercise was conducted involving the five member survey team on 100 diagnosed cases of dental fluorosis. The members again screened 74 children with dental fluorosis in the field to categorize in to different grades of fluorosis for assessment of inter-examiner reliability. RESULTS: The ICMR criteria showed more difference in agreement in very mild and mild categories during calibration. The inter-examiner reliability (κ) ranged from 0.59-1. The criteria was further modified and inter- examiner reliability (κ) found to be 0.83-0.98 which was almost perfect agreement. INTERPRETATION & CONCLUSIONS: The tool developed by the ICMR to assess dental fluorosis can be used in a field set up by non-dental personnel reliably with high degree of reproducibility.


Assuntos
Estudos Epidemiológicos , Fluorose Dentária/diagnóstico por imagem , Fluorose Dentária/diagnóstico , Adolescente , Feminino , Fluorose Dentária/epidemiologia , Fluorose Dentária/patologia , Humanos , Índia/epidemiologia , Masculino
11.
J Bone Miner Res ; 31(11): 1955-1966, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27257137

RESUMO

Enamel defects resulting from environmental conditions and way of life are public health concerns because of their high prevalence. Because their etiology is unclear, the aim of this study was to analyze the various forms of enamel hypomineralization, and to characterize the genes involved in this process to determine the mechanisms involved in disruptions of amelogenesis. We used bisphenol A (BPA) and fluoride as models; both are commonly encountered in human populations and utilized in dentistry. Wistar rats were chronically exposed to 5 µg/kg/day BPA from day 1 of gestation to day 65 after birth (P65) and 5 mM fluoride from P21 to P65. Resulting enamel defects were comparable to the human enamel pathologies molar incisor hypomineralization (MIH) and dental fluorosis (DF) respectively, and were more severe in rats exposed to both agents than to each agent alone. Large-scale transcriptomic analysis of dental epithelium showed a small group of genes the expression of which was affected by exposure to BPA or NaF. Among the most modulated, many are directly involved in amelogenesis (Amelx, Enam, Klk4, Mmp12, Slc26a4, and Slc5a8), and can be regrouped as forming the "hypomineralization enameloma." Each of these gene expression perturbations may contribute to enamel defects. Exposure to BPA weakens enamel, making it more prone to generate frequent mineralization defects MIH and DF. Our study identifies hypomineralization genes that may enable the use of dental enamel as an early marker of exposure to environmental toxicants because of its unique ability to retrospectively record ameloblast pathophysiology. © 2016 American Society for Bone and Mineral Research.


Assuntos
Compostos Benzidrílicos/efeitos adversos , Progressão da Doença , Fluorose Dentária/patologia , Fenóis/efeitos adversos , Animais , Criança , Esmalte Dentário/metabolismo , Epitélio/efeitos dos fármacos , Feminino , Fluorose Dentária/genética , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Masculino , Análise de Sequência com Séries de Oligonucleotídeos , Peptídeo Hidrolases/metabolismo , Ratos Wistar , Fluoreto de Sódio/farmacologia , Adulto Jovem
12.
Arch Oral Biol ; 70: 16-23, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27300491

RESUMO

OBJECTIVE: The prevalence and severity of dental fluorosis in primary teeth are different from permanent teeth. Previous animal models of dental fluorosis mainly focus on juvenile rats, mice and zebrafish. Our experiment aims to set a dental fluorosis model using zebrafish larva and explore the characteristics of the first generation teeth by fluoride treatment. MATERIALS AND METHODS: After the zebrafish eggs were laid, they were exposed to excess fluoride (19ppm, 38ppm and 76ppm) for five days. The morphological characteristics of first generation teeth were examined by H&E staining, whole-mount alizarin red and alcian blue staining, and scanning electron microscope (SEM) technique. RESULTS: With whole-mount alizarin red and alcian blue staining, the tooth cusps presented red in normal control. 19ppm and 38ppmm fluoride resulted in extensive red staining from tooth cusps to the lower 1/3 of teeth. 76ppm fluoride caused malformed teeth with uneven red staining. H&E staining showed that excess fluoride caused cystic-like changes in 38ppm and 76ppm groups. SEM revealed the dose dependent pathological changes in zebrafish enameloid with fluoride treatment. Based on SEM findings, we set 0-4 dental fluorosis index (DFI) score to label the severity of dental fluorosis. CONCLUSIONS: Excess fluoride presented a dose dependent fluorosis changes in the teeth of zebrafish larva. The DFI scores in our experiment reflect dose dependent fluorosis changes in a good way and will benefit the future research of dental fluorosis.


Assuntos
Modelos Animais de Doenças , Fluoretos/toxicidade , Fluorose Dentária/patologia , Peixe-Zebra , Animais , Cariostáticos/administração & dosagem , Cariostáticos/toxicidade , Esmalte Dentário/química , Esmalte Dentário/efeitos dos fármacos , Esmalte Dentário/patologia , Relação Dose-Resposta a Droga , Feminino , Fluoretos/administração & dosagem , Fluorose Dentária/diagnóstico por imagem , Fluorose Dentária/metabolismo , Larva , Masculino , Microscopia Eletrônica de Varredura , Fosfatos/administração & dosagem , Fosfatos/toxicidade , Calcificação de Dente/efeitos dos fármacos
13.
Biol Trace Elem Res ; 174(1): 150-157, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27052310

RESUMO

This study evaluated dental fluorosis of the incisors and immunoreactivity in the brain tissues of rats given chronic fluoride doses pre- and postnatally. Female rats were given drinking water with 0, 30 or 100 ppm fluoride ad libitum throughout gestation and the nursing period. In addition, 63 male offspring were treated with the same water regimens as the mothers after weaning and were followed for 1, 3 or 5 months. The upper and lower incisors were collected, and all teeth were examined under a stereomicroscope and scored by two blinded examiners using a modified rodent enamel fluorosis index. Cortical, hippocampal and cerebellar brain samples were evaluated morphologically and immunohistochemically. All fluoride-treated pups were born with low body weight (p = 0.001). All animals from the fluoride groups had enamel fluorosis with defects of various degrees. The increase in the dental fluorosis scores in the fluoride treatment groups was significant (p < 0.01). The catalase immunoreactivity in the 30- and 100-ppm fluoride groups was significantly higher than that in the controls after 1, 3 and 5 months (p < 0.001). In conclusion, this study showed that rats with dental fluorosis had catalase immunoreactivity in the brain tissues, which may reflect the neurobehavioral toxicity of fluoride.


Assuntos
Encéfalo , Catalase/metabolismo , Fluoretos/toxicidade , Fluorose Dentária , Efeitos Tardios da Exposição Pré-Natal , Animais , Encéfalo/enzimologia , Feminino , Fluorose Dentária/enzimologia , Fluorose Dentária/patologia , Masculino , Gravidez , Efeitos Tardios da Exposição Pré-Natal/induzido quimicamente , Efeitos Tardios da Exposição Pré-Natal/enzimologia , Efeitos Tardios da Exposição Pré-Natal/patologia , Ratos , Ratos Wistar
14.
Micron ; 84: 54-60, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26930005

RESUMO

The enamel surfaces of fluorotic teeth were studied by scanning electron stereomicroscopy. Different whitening treatments were applied to 25 pieces to remove stains caused by fluorosis and their surfaces were characterized by stereomicroscopy in order to obtain functional and amplitude parameters. The topographic features resulting for each treatment were determined through these parameters. The results obtained show that the 3D reconstruction achieved from the SEM stereo pairs is a valuable potential alternative for the surface characterization of this kind of samples.


Assuntos
Esmalte Dentário/ultraestrutura , Fluorose Dentária/patologia , Imagem Tridimensional/instrumentação , Microscopia Eletrônica de Varredura/métodos , Adulto , Esmalte Dentário/química , Humanos , Dente/química
15.
PLoS One ; 11(2): e0147427, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26895178

RESUMO

Dental fluorosis has recently been diagnosed in wild marsupials inhabiting a high-fluoride area in Victoria, Australia. Information on the histopathology of fluorotic marsupial enamel has thus far not been available. This study analyzed the developmental and post-eruptive defects in fluorotic molar enamel of eastern grey kangaroos (Macropus giganteus) from the same high-fluoride area using light microscopy and backscattered electron imaging in the scanning electron microscope. The fluorotic enamel exhibited a brownish to blackish discolouration due to post-eruptive infiltration of stains from the oral cavity and was less resistant to wear than normally mineralized enamel of kangaroos from low-fluoride areas. Developmental defects of enamel included enamel hypoplasia and a pronounced hypomineralization of the outer (sub-surface) enamel underneath a thin rim of well-mineralized surface enamel. While the hypoplastic defects denote a disturbance of ameloblast function during the secretory stage of amelogenesis, the hypomineralization is attributed to an impairment of enamel maturation. In addition to hypoplastic defects, the fluorotic molars also exhibited numerous post-eruptive enamel defects due to the flaking-off of portions of the outer, hypomineralized enamel layer during mastication. The macroscopic and histopathological lesions in fluorotic enamel of M. giganteus match those previously described for placental mammals. It is therefore concluded that there exist no principal differences in the pathogenic mechanisms of dental fluorosis between marsupial and placental mammals. The regular occurrence of hypomineralized, opaque outer enamel in the teeth of M. giganteus and other macropodids must be considered in the differential diagnosis of dental fluorosis in these species.


Assuntos
Esmalte Dentário/efeitos dos fármacos , Esmalte Dentário/patologia , Exposição Ambiental/efeitos adversos , Fluoretos/efeitos adversos , Fluorose Dentária/etiologia , Fluorose Dentária/patologia , Erupção Dentária/efeitos dos fármacos , Fatores Etários , Amelogênese/efeitos dos fármacos , Animais , Osso e Ossos/metabolismo , Feminino , Fluoretos/metabolismo , Fluorose Dentária/diagnóstico por imagem , Macropodidae , Masculino , Dente Molar , Radiografia
16.
J Dent ; 46: 42-6, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26808157

RESUMO

OBJECTIVES: Enamel fluorosis is a hypomineralization caused by chronic exposure to high levels of fluoride during tooth development. Previous research on the relationship between enamel fluoride content and fluorosis severity has been equivocal. The current study aimed at comparing visually and histologically assessed fluorosis severity with enamel fluoride content. METHODS: Extracted teeth (n=112) were visually examined using the Thylstrup and Fejerskov Index for fluorosis. Eruption status of each tooth was noted. Teeth were cut into 100 µm slices to assess histological changes with polarized light microscopy. Teeth were categorized as sound, mild, moderate, or severe fluorosis, visually and histologically. They were cut into squares (2 × 2 mm) for the determination of fluoride content (microbiopsy) at depths of 30, 60 and 90 µm from the external surface. RESULTS: Erupted teeth with severe fluorosis had significantly greater mean fluoride content at 30, 60 and 90 µm than sound teeth. Unerupted teeth with mild, moderate and severe fluorosis had significantly greater mean fluoride content than sound teeth at 30 µm; unerupted teeth with mild and severe fluorosis had significantly greater mean fluoride content than sound teeth at 60 µm, while only unerupted teeth severe fluorosis had significantly greater mean fluoride content than sound teeth at 90 µm. CONCLUSIONS: Both erupted and unerupted severely fluorosed teeth presented higher mean enamel fluoride content than sound teeth. CLINICAL SIGNIFICANCE: Data on fluoride content in enamel will further our understanding of its biological characteristics which play a role in the management of hard tissue diseases and conditions.


Assuntos
Esmalte Dentário/química , Esmalte Dentário/patologia , Fluoretos/administração & dosagem , Fluoretos/efeitos adversos , Fluorose Dentária/etiologia , Esmalte Dentário/efeitos dos fármacos , Relação Dose-Resposta a Droga , Fluoretos/análise , Fluorose Dentária/patologia , Humanos , Microscopia de Polarização , Odontogênese/efeitos dos fármacos , Dente não Erupcionado/química , Dente não Erupcionado/patologia
17.
Biomed Res Int ; 2015: 274852, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26339601

RESUMO

Fluorosis is caused by excess of fluoride intake over a long period of time. Aberrant change in the Runt-related transcription factor 2 (RUNX2) mediated signaling cascade is one of the decisive steps during the pathogenesis of fluorosis. Up to date, role of fluoride on the epigenetic alterations is not studied. In the present study, global expression profiling of short noncoding RNAs, in particular miRNAs and snoRNAs, was carried out in sodium fluoride (NaF) treated human osteosarcoma (HOS) cells to understand their possible role in the development of fluorosis. qPCR and in silico hybridization revealed that miR-124 and miR-155 can be directly involved in the transcriptional regulation of Runt-related transcription factor 2 (RUNX2) and receptor activator of nuclear factor κ-B ligand (RANKL) genes. Compared to control, C/D box analysis revealed marked elevation in the number of UG dinucleotides and D-box sequences in NaF exposed HOS cells. Herein, we report miR-124 and miR-155 as the new possible players involved in the development of fluorosis. We show that the alterations in UG dinucleotides and D-box sequences of snoRNAs could be due to NaF exposure.


Assuntos
Subunidade alfa 1 de Fator de Ligação ao Core/biossíntese , Fluorose Dentária/genética , MicroRNAs/biossíntese , Osteossarcoma/genética , Ligante RANK/biossíntese , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Subunidade alfa 1 de Fator de Ligação ao Core/genética , Fluorose Dentária/patologia , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , MicroRNAs/genética , Osteossarcoma/complicações , Osteossarcoma/tratamento farmacológico , Osteossarcoma/patologia , Ligante RANK/genética , RNA Nucleolar Pequeno/genética , Transdução de Sinais/efeitos dos fármacos , Fluoreto de Sódio/toxicidade
18.
Indian J Dent Res ; 26(3): 248-51, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26275189

RESUMO

AIMS: To observe and characterize the histological features of fluorosed teeth under light and confocal microscope (CFM). MATERIALS AND METHODS: A total of 25 fluorosed teeth and 5 normal teeth were collected from dentists across Dindigul, a known endemic area of fluorosis in South India. Ground sections of respective teeth were observed under light microscope and the sections were subsequently stained with acridine orange and studied under CFM. RESULTS: Histological changes were observed in the ground sections of fluorosed teeth as compared with the normal teeth. Depending on the degree of fluorosis, the affected teeth showed various features of hypomineralization in enamel and dentin. CONCLUSIONS: Fluoride interacts with both mineral phases and organic macromolecules by strong ionic and hydrogen bonds resulting in incomplete crystal growth at prism peripheries. This presents as hypomineralization of enamel and dentin.


Assuntos
Fluorose Dentária/patologia , Microscopia Confocal/métodos , Adulto , Humanos
19.
Environ Monit Assess ; 187(8): 497, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26160742

RESUMO

Chronic industrial fluoride toxicosis in the forms of dental, skeletal and non-skeletal fluorosis was investigated in 162 villagers (94 males and 78 females) above 15 years of age living in the vicinity of superphosphate fertilizer plants located approximately 12 km south of Udaipur city of Rajasthan, India. Out of these villagers, 90 (55.5%) and 29 (18.0%) were found to be afflicted with mild to severe dental and skeletal fluorosis, respectively. Dental fluorosis characterized with light to deep-brownish bilaterally striated horizontal lines, pits or patches and fine dots or granules was noted on incisor teeth of villagers. Irregular wearing, excessive corrosions (abrasions), dark-brownish pigmentation of exposed cementum and dentine material, diastem as between teeth, pronounced loss of tooth supporting bone with recession and bulging of gingiva (gum) were also present in subjects of older age group (>55 years). Among 29 (18.0%) individuals, mild to moderate manifestations of skeletal fluorosis such as crippling, kyphosis, invalidism and genu-varum syndrome were found. In these fluorotic subjects pain/rigidity in major joints viz. neck, back, hip, knee and shoulder was also found. None of the fluorotic subjects showed evidence of genu-valgum syndrome. Other signs of chronic industrial fluoride intoxication in soft tissues (non-skeletal fluorosis) included colic, intermittent diarrhoea or constipation, bloating, polyuria and polydipsia. These findings indicate that surrounding environment of superphosphate fertilizer plants is contaminated with fluoride emission, which in turn is causing diverse ill health effects in humans which are discussed.


Assuntos
Doenças Ósseas/epidemiologia , Difosfatos/toxicidade , Monitoramento Ambiental , Fertilizantes/toxicidade , Fluorose Dentária/epidemiologia , Adolescente , Adulto , Idoso , Doenças Ósseas/induzido quimicamente , Doenças Ósseas/patologia , Estudos Transversais , Difosfatos/análise , Feminino , Fertilizantes/análise , Fluorose Dentária/patologia , Humanos , Índia , Masculino , Pessoa de Meia-Idade , Prevalência
20.
Zhonghua Kou Qiang Yi Xue Za Zhi ; 50(5): 307-12, 2015 May.
Artigo em Chinês | MEDLINE | ID: mdl-26082054

RESUMO

OBJECTIVE: To investigate the ultrastructure of enamel in the mandibular incisor tooth in a rat model of dental fluorosis. METHODS: Thirty 5-week-old male and female rats of SD strain were divided into three groups of ten. The animals in the control group were maintained for 8 weeks on pure deionized water, in the low-fluoride group deionized water with 22.5 mg/L of fluorine (50 mg/L NaF) was used, and in the high-fluoride group deionized water with 45 mg/L of fluorine (100 mg/L NaF) was used. All specimens examined were obtained from the mandibular incisors. Mid-sagittal ground sections were prepared from the direction of incisal point of each incisor for scanning electron microscopy (SEM) and atomic force microscopy (AFM). RESULTS: According to the SEM results, the prisms in the control group had a complete and clear column structure with closely packed enamel rods or enamel prisms. The prisms in the high-fluoride experimental group were collapsed and showed curved and fractured crystallites. The level of prism structural changes in the low-fluoride experimental group was in between that of the control group and the high-fluoride group. AFM for the middle layer enamel showed an average roughness (Ra) of (550.6±32.0) nm in the control group, (415.0±24.2) nm in the low-fluoride group, and (194.3±11.3) nm for the high-fluoride group. There was significant difference between the high-fluoride group and the control group (P<0.05). CONCLUSIONS: Formation of rat enamel in the high fluoride environment presented obvious structural collapse and no clearance between prisms. Such changes appear to indicate a loss of normal prism structure in rat enamels from exposure to high levels of fluorine during the maturation period.


Assuntos
Esmalte Dentário/ultraestrutura , Fluorose Dentária/patologia , Animais , Feminino , Fluorose Dentária/diagnóstico , Incisivo/ultraestrutura , Masculino , Mandíbula , Microscopia de Força Atômica , Microscopia Eletrônica de Varredura , Ratos , Ratos Sprague-Dawley
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