Abstract

Renal impairment in children is associated with tooth defects that include enamel pitting and hypoplasia. However, the specific effects of uremia on tooth formation are not known. In this study, we used rat mandibular incisors, which continuously erupt and contain all stages of tooth formation, to characterize the effects of uremia on tooth formation. We also tested the hypothesis that uremia aggravates the fluoride (F)-induced changes in developing teeth. Rats were subjected to a two-stage 5/6 nephrectomy or sham operation and then exposed to 0 (control) or 50 ppm NaF in drinking water for 14 days. The effects of these treatments on food intake, body growth rate, and biochemical serum parameters for renal function and calcium metabolism were monitored. Nephrectomy reduced food intake and weight gain. Intake of F by nephrectomized rats increased plasma F levels twofold and further decreased food intake and body weight gain. Uremia affected formation of dentin and enamel and was more extensive than the effect of F alone. Uremia also significantly increased predentin width and induced deposition of large amounts of osteodentin-like matrix-containing cells in the pulp chamber. In enamel formation, the cells most sensitive to uremia were the transitional-stage ameloblasts. These data demonstrate that intake of F by rats with reduced renal function impairs F clearance from the plasma and aggravates the already negative effects of uremia on incisor tooth development.

Excerpt:

In summary, these studies show that tooth development is disturbed under uremic conditions. The effects of uremia are primarily in the dentin but also occur in enamel, resulting in hypoplasia and pitting of the enamel surface. The crown portion of human central incisors (the most aesthetically visible teeth) forms up to approximately 4 years of age, with the second permanent molars forming by about 8 years of age. Therefore, children who present with renal insufficiency before the age of 8 years are at risk for tooth defects. These effects will be more severe in the presence of F, and ingestion of F by young children with renal failure (i.e. F supplements or swallowing F-containing toothpaste) is contraindicated, as suggested previously.

Print PDF

• Related Studies :

  • Oro-dental health in children with chronic renal failure and after renal transplantation: a clinical review

    As a consequence of chronic renal failure (CRF) and its treatment, a number of oro-dental changes occur that persist after the end-stage is reached. An early effect is enamel hypoplasia due to a defect of enamel development and mineralisation. This is usually reparable to a high aesthetic standard using dental

  • Enamel hypoplasia in children with renal disease in a fluoridated area

    The aim of this study was to compare the frequency of enamel hypoplasia in children with renal disease and healthy children, all of whom live in a fluoridated area. A cross-sectional study was made in 42 children divided into 2 groups. To describe enamel changes, 3 diagnostic criteria were applied:

  • Skeletal fluorosis in humans: a review of recent progress in the understanding of the disease

    Endemic skeletal fluorosis is a chronic metabolic bone and joint disease caused by ingesting large amounts of fluoride either through water or rarely from foods of endemic areas. Fluoride is a cumulative toxin which can alter accretion and resorption of bone tissue. It also affects the homeostasis of bone mineral

  • Coal-burning roasted corn and chili as the cause of dental fluorosis for children in southwestern China.

    To find the pathologic cause of the children's dental fluorosis in southwestern China, diet structure before the age of 6 and prevalence rate of dental fluorosis (DF) of 405 children were investigated, and the fluorine and arsenic content of several materials were determined. The prevalence rate of DF of children

  • Association Between Dietary Patterns and Fluorosis in Guizhou, China.

    Objective: Many studies have explored the effects of individual foods or nutrients on fluorosis, but no studies have focused on dietary patterns. This study examined the relationship between dietary patterns and coal-burning fluorosis in Guizhou, China. Methods: This 1:1 matched case-control study was conducted in Zhijin County of Guizhou province with

• Related FAN Content :

  • Annapolis: Water Fluoridation Linked to Death of Dialysis Patient

    EVENING CAPITAL (Annapolis, Maryland) November 29, 1979 Fluoride Linked to Death by Mary Ann Kryzankowicz Staff Writer Fluoride poisoning has been definitely linked to the death of a 65-year-old kidney dialysis patient who became ill during a blood cleaning process Nov 11. State Medical Examiner Dr. (illegible) Guard has ruled that Lawrence Blake, 65, of Arundel

  • Fluoridation of drinking water and chronic kidney disease: Absence of evidence is not evidence of absence

    A fairly substantial body of research indicates that patients with chronic renal insufficiency are at an increased risk of chronic fluoride toxicity. Patients with reduced glomerular filtration rates have a decreased ability to excrete fluoride in the urine. These patients may develop skeletal fluorosis even at 1 ppm fluoride in the drinking water.

  • Racial Disparities in Dental Fluorosis

    In 2005, the Centers for Disease Control published the results of a national survey of dental fluorosis conducted between 1999 and 2002. According to the CDC, black children in the United States have significantly higher rates of dental fluorosis than either white or Hispanic children. This was not the first time that black children were found to suffer higher rates of dental fluorosis. At least five other studies -- dating as far back as the 1960s -- have found black children in the United States are disproportionately impacted by dental fluorosis.

  • Mayo Clinic: Fluoridation & Bone Disease in Renal Patients

    The available evidence suggests that some patients wtih long-term renal failure are being affected by drinking water with as little as 2 ppm fluoride. The finding of adverse effects in patients drinking water with 2 ppm of fluoride suggests that a few similar cases may be found in patients imbibing 1 ppm, especially if large volumes are consumed, or in heavy tea drinkers. The finding of adverse effects in patients drinking water with 2 ppm of fluoride suggests that a few similar cases may be found in patients imbibing 1 ppm, especially if large volumes are consumed, or in heavy tea drinkers and if fluoride is indeed the cause. It would seem prudent, therefore, to monitor the fluoride intake of patients with renal failure living in high fluoride areas.

  • Unheeded Warnings: Government Health Authorities Ignore Fluoride Risk for Kidney Patients

    Despite the well known fact that individuals with kidney disease are at much higher risk of fluoride toxicity than the general population, there has yet to be any attempt in the United States, or any other country that practices mass-scale water fluoridation to determine the prevalence of fluoride-related effects (e.g.,