Abstract

This study examined the relationship between transient peak plasma fluoride levels (subcutaneous injections) as well as lower but relatively constant levels (subcutaneous constant infusion) and the occurrence of disturbances in the enamel mineralization of the rat incisor as determined microradiographically. The fluoride doses were administered for 1 week, and the animals were killed 2 weeks later. Once daily peak plasma fluoride levels of 10 µM were uniformly associated with disturbances in the mineralization of the enamel, but once daily peak levels of 5 µM were not. Neither were twice daily 5-µM peaks. Relatively constant plasma fluoride levels, which averaged 3.3 µM, were associated with an increased incidence of changes in enamel formation and levels of 4.7 µM consistently associated with disturbances in enamel mineralization. These findings suggest that (1) the rat is a better model for the study of human enamel fluorosis than previously believed, and (2) slightly elevated but relatively constant plasma fluoride levels are more likely to be associated with the occurrence of fluorotic disturbances in the mineralization of enamel than are the more rare high and transient peak levels.

*Abstract online at https://europepmc.org/article/MED/6956449

• Related Studies :

  • Uncoupling protein-2 is an antioxidant that is up-regulated in the enamel organ of fluoride-treated rats

    Dental fluorosis is characterized by subsurface hypomineralization and retention of enamel matrix proteins. Fluoride (F-) exposure generates reactive oxygen species (ROS) that can cause endoplasmic reticulum (ER)-stress. We therefore screened oxidative stress arrays to identify genes regulated by F- exposure. Vitamin E is an antioxidant so we asked if a

  • Possible Association Between Polymorphisms in ESR1, COL1A2, BGLAP, SPARC, VDR, and MMP2 Genes and Dental Fluorosis in a Population from an Endemic Region of West Bengal.

    Dental fluorosis (DF) is the most prevalent form of fluorosis in India affecting millions of people all over the country. As estrogen receptor 1 (ESR1), collagen type 1 alpha 2 (COL1A2), bone ?-carboxyglutamic acid protein (BGLAP), secreted protein acidic and cysteine-rich (SPARC), vitamin D receptor (VDR), and matrix metallopeptidase 2

  • JNK Signaling Pathway Mediates Fluoride-Induced Upregulation of CK1a during Enamel Formation.

    Fluorosis is a defect in the enamel mineral content caused by excessive fluoride intake during amelogenesis; the interaction of various factors in the development and progression of fluorosis has not been defined. Casein kinase 1a (CK1a) is constitutively active in cells and is involved in diverse cellular processes; however, its

  • Fluorosed mouse ameloblasts have increased SATB1 retention and Gaq activity

    Dental fluorosis is characterized by subsurface hypomineralization and increased porosity of enamel, associated with a delay in the removal of enamel matrix proteins. To investigate the effects of fluoride on ameloblasts, A/J mice were given 50 ppm sodium fluoride in drinking water for four weeks, resulting serum fluoride levels of

  • Utilization of ( 3 H)-serine by ameloblasts of rats receiving sub-mottling doses of fluoride.

    Five-day-old Wistar rats were given three intraperitoneal injections at 2-hourly intervals of a solution of sodium fluoride in 0.9 per cent sodium chloride. Three fluoride levels were used: a mottling dose of 3 mgF/kg body weight; and two sub-mottling doses, 0.05 mg and 0.01 mgF/kg body weight. Thirty minutes after

• 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

  • Dental Fluorosis in the U.S. 1950-2004

    Before the widespread use of fluoride in dentistry, dental fluorosis was rarely found in western countries. Today, with virtually every toothpaste now containing fluoride, and most U.S. water supplies containing fluoride chemicals, dental fluorosis rates have reached unprecedented levels. In the 1950s, it was estimated that only 10% of children in

  • Moderate/Severe Dental Fluorosis

    In its "moderate" and severe forms, fluoride causes a marked increase in the porosity of the enamel. After eruption into mouth, the porous enamel of moderate to severe fluorosis readily takes up stain, creating permanent brown and black discolorations of the teeth. In addition to extensive staining, teeth with moderate to severe fluorosis are more prone to attrition and wear - leading to pitting, chipping, and decay.

  • Dental Fluorosis: The "Cosmetic" Factor

    Any condition that can cause children to be embarrassed about their physical appearance can have significant consequences on their self-esteem and confidence.  Researchers have repeatedly found that "physical appearance [is] the best predictor of self-esteem" in adolescents, (Harter 2000) and that facial attractiveness, particularly the appearance of one's teeth, is a