Abstract

Fluorosed enamel is caused by exposure to fluoride during tooth formation. The objective of this study was to determine whether epithelial ameloblast-lineage cells, derived from the human enamel organ, are directly affected by micromolar concentrations of fluoride. Cells were cultured in the presence of fluoride, and proliferation was measured by BrdU incorporation. The effect of 0, 10, or 20 microM fluoride on apoptosis was determined by the flow cytometry apoptotic index. The effects of fluoride on gene expression were investigated by SuperArray microarray analysis and real-time PCR. Fluoride had a biphasic effect on cell proliferation, with enhanced proliferation at 16 microM, and reduced proliferation at greater than 1 mM F. Flow cytometry showed that both 10 microM and 20 microM NaF significantly increased the apoptotic index of ameloblast-lineage cells. There was no general effect of fluoride on gene expression. These results indicate multiple effects of micromolar fluoride on ameloblast-lineage cells.

• Related Studies :

  • Fluoride induced endoplasmic reticulum stress and calcium overload in ameloblasts

    OBJECTIVE:  The aim of the study was to evaluate the involvement of endoplasmic reticulum stress and intracellular calcium overload on the development of dental fluorosis. METHODS:  We cultured and exposed rat ameloblast HAT-7 cells to various concentrations of fluoride and measured apoptosis with flow cytometry and intracellular Ca2+ changes using confocal

  • LS8 cell apoptosis induced by NaF through p-ERK and p-JNK - a mechanism study of dental fluorosis

    OBJECTIVE: To investigate the possible biological mechanism of dental fluorosis at a molecular level. MATERIAL AND METHODS: Cultured LS8 were incubated with serum-free medium containing selected concentrations of NaF (0???2?mM) for either 24 or 48?h. Subcellular microanatomy was characterized using TEM; meanwhile, selected biomolecules were analysed using various biochemistry techniques. Transient

  • Protective effect of lycopene on fluoride-induced ameloblasts apoptosis and dental fluorosis through oxidative stress-mediated Caspase pathways

    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

  • High-fluoride promoted phagocytosis-induced apoptosis in a matured ameloblast-like cell line

    Endocytosis and phagocytosis are important physiologic activities occurring during ameloblast differentiation. We have previously found that excess fluoride inhibited ameloblasts endocytotic functions. Here, we hypothesized that increasing amounts of fluoride may affect ameloblast phagocytotic function during their differentiation. Using cell culture, we first induced maturation of the mouse ameloblast-like LS8

  • Biphasic Functions of Sodium Fluoride (NaF) in Soft and in Hard Periodontal Tissues.

    Sodium fluoride (NaF) is widely used in clinical dentistry. However, the administration of high or low concentrations of NaF has various functions in different tissues. Understanding the mechanisms of the different effects of NaF will help to optimize its use in clinical applications. Studies of NaF and epithelial cells, osteoblasts,

• Related FAN Content :

  • Mechanisms by Which Fluoride Causes Dental Fluorosis Remain Unknown

    When it comes to how fluoride impacts human health, no tissue in the body has been studied more than the teeth. Yet, despite over 50 years of research, the mechanism by which fluoride causes dental fluorosis (a hypo-mineralization of the enamel that results in significant staining of the teeth) is not

  • Dental Fluorosis Is a "Hypo-mineralization" of Enamel

    Teeth with fluorosis have an increase in porosity in the subsurface enamel ("hypomineralization"). The increased porosity of enamel found in fluorosis is a result of a fluoride-induced impairment in the clearance of proteins (amelogenins) from the developing teeth. Despite over 50 years of research, the exact mechanism by which fluoride impairs amelogin

  • Community Fluorosis Index (CFI)

    The current Community Fluorosis Index for U.S. adolescents as a whole (from both fluoridated and non-fluoridated areas) is roughly 5 times higher than the CFI health authorities predicted for fluoridated areas when fluoridation first began. It is also higher than the CFI that the NIDR found in fluoridated areas back in the 1980s. It is readily apparent, therefore, that children are ingesting far more fluoride than was the case in the 1950s, and even as recently as the 1980s.

  • Severe Dental Fluorosis: Perception and Psychological Impact

    [caption id="attachment_8879" align="aligncenter" width="550"] Severe fluorosis - Photograph by David Kennedy, DDS[/caption] In its severe forms, dental fluorosis causes highly disfiguring brown and black staining of the teeth, which can cause chronic embarrassment and social anxiety for the impacted child. In 1984, a panel from the National Institute of Mental Health (NIMH) warned

  • Diagnostic Criteria for Dental Fluorosis: The Thylstrup-Fejerskov (TF) Index

    The traditional criteria (the "Dean Index") for diagnosing dental fluorosis was developed in the first half of the 20th century by H. Trendley Dean. While the Dean Index is still widely used in surveys of fluorosis -- including the CDC's national surveys of fluorosis in the United States -- dental