title: Ultrastructural morphometric analysis of ameloblasts exposed to fluoride during tooth development.
abstract: Since a considerable amount of the world population is exposed to high doses of fluoride, it is of special concern to investigate its action mechanisms during dental enamel development. In this study, the toxicity of fluoride in ameloblasts during enamel development was evaluated by means of ultrastructural morphometric analysis. A total of 18 male Wistar rats were distributed into three groups. In Group I, the animals received deionized drinking water ad libitum (negative control) and in Groups II and III, they received sodium fluorided (NaF) drinking water at doses of 7 and 100 ppm ad libitum, respectively, for 6 weeks. Morphometric data were expressed as volume density of the most significant organelles present in the secretory and maturation phases of amelogenesis such as RER, granules, lysosomes, phagic vacuoles, microfilaments and mitochondria. The results showed that the volume density of mitochondria in the 100 ppm experimental group was 29% (P < 0.05) higher than the control group in secretory ameloblasts. No remarkable differences were found in maturation ameloblasts for all organelles evaluated. Taken together, these data indicate that NaF at high doses is able to induce cellular damage in secretory ameloblasts, whereas no noxious effect was observed during maturation stage of amelogenesis as depicted by ultrastructural analysis.
authors.affiliation: Department of Health Sciences, Federal University of Sao Paulo, Av. Ana Costa 95, Santos 110601-001, SP, Brazil. ak92@hotmail.com
authors.forename: Daniel A
authors.initials: DA
authors.lastname: Ribeiro
authors.forename: Luciane
authors.initials: L
authors.lastname: Hirota
authors.forename: Tania M
authors.initials: TM
authors.lastname: Cestari
authors.forename: Daniele S
authors.initials: DS
authors.lastname: Ceolin
authors.forename: Rumio
authors.initials: R
authors.lastname: Taga
authors.forename: Gerson F
authors.initials: GF
authors.lastname: Assis
mesh_terms: D000565:Ameloblasts / Q000187:drug effects / Q000502:physiology / Q000648:ultrastructure*; D000566:Amelogenesis / Q000187:drug effects*; D000818:Animals; D005459:Fluorides / Q000009:adverse effects*; D007180:Incisor / Q000187:drug effects / Q000254:growth & development / Q000648:ultrastructure*; D008297:Male; D051381:Rats; D017208:Rats, Wistar
chemical_list: D005459:Fluorides