Résumé
O flúor (F), na forma de fluoreto de sódio (NaF), é um elemento presente no cotidiano de quase a totalidade da população brasileira, sendo usado na água de abastecimento (Brasil) e também como terapêutico para osteoporose (comumente na Europa). Assim sendo, é importante o entendimento do efeito do flúor no reparo ósseo. Neste estudo foram utilizados 4 grupos com ratos Wistar de 80 dias (n=200), os quais receberam água de beber contendo 5, 15 e 50 ppm de flúor e água deionizada (grupo controle) durante todo experimento. Esses animais tiveram o incisivo superior direito extraído. Os animais foram eutanasiados O hora, 7, 14, 21 e 30 dias após a extração, sendo coletado sangue (análise da concentração de flúor), a região do alvéolo dental para análise microscópica (análise histológica e morfometria) e extração de proteínas referentes ao reparo ósseo (metaloproteinases de matriz - MMPs 2 e 9). A análise de concentração de flúor no plasma sangüíneo mostrou maior presença desse elemento no grupo tratado com 50 ppm de F nos períodos de 21 e 30 dias. A análise histológica detectou osso neoformado em todos os animais após 30 dias, porém o grupo de 50 ppm de F apresentou menor formação óssea que os outros grupos. A análise morfométrica mostrou um aumento na densidade de volume de osso neoformado, entre 7 e 30 dias, nos grupos controle, 5, 15 e 50 ppm de F, com concomitante diminuição na densidade de volume de tecido conjuntivo e coágulo sangüíneo. A atividade da MMP-2 foi mais acentuada no período inicial, enquanto a MMP-9 teve maior atividade no período final. Concluiu-se que o F, em altas concentrações, pode retardar o reparo alveolar diminuindo a formação de novo tecido ósseo, associado a um atraso na remissão do coágulo.
The fluorine (F), in the sodium fluoride (NaF) form, is an element daily present for most people, being used in water supply (Brazil) and also as therapy for osteoporosis (common in Europe). In such case it is important the understanding of the effect of fluoride in physiologic repair in bone tissue. This study used 4 groups of rats for 80 days (n = 200), which received drinking water containing 5, 15 and 50 ppm of fluoride, and deionized water (control group) throughout experimento These animais had the right upper incisor extracted. The animais were euthanized O hours, 7, 14, 21 and 30 days after extraction, and blood collected (analysis of the concentration of fluorine), the region of the dental alveolus for microscopic exa'mination (histological analysis and morphometry) and extraction of proteins for the bone repair (the matrix metalloproteinases - MMP 2 and 9). The analysis of concentration of fluoride in blood plasma showed greater presence of that element in the group treated with 50 ppm of F in periods of 21 and 30 days. Histological analysis detected neoformed bone in ali animais after 30 days, but the group of 50 ppm F showed lower bone formation than the other groups. Morphometric analysis showed an increase in the volume density of neoformed bone, between 7 and 30 days in control groups, 5, 15 and 50 ppm F, with a concomitant decrease in the volume density of connective tissue and blood dot. The activity of MMP-2 was more pronounced in the initial period, while MMP-9 had higher activity in the 30 days. It was concluded that the F, in high concentrations, may delay the tooth socket repair reducing the formation of new bone tissue, associated with a delay in remission of blood clot.
Sujets)
Animaux , Mâle , Fluorure de sodium/administration et posologie , Fluorure de sodium/sang , Matrix metalloproteinases/physiologie , Régénération osseuse , Alvéole dentaire , Analyse de variance , Phosphatase alcaline/physiologie , Phosphatase alcaline/sang , Halogénation , Ostéoclastes , Rat WistarRésumé
There is a paucity of data on the amount of fluoride absorbed in humans from whole cooked food; especially a combination of different foods taken at regular meal times. The present study was thus aimed at estimating the amount of fluoride present and absorbed in humans from four regional representative meals viz. North Indian Vegetarian, North Indian Non-vegetarian, South Indian and East Indian. Twenty five healthy human volunteers aged 22-35 years participated in the study and each diet was tested on five volunteers. Each test diet was weighed into six equal parts, one part was kept for estimation of fluoride content and remaining five were given one each to the five test subjects in each of the four test diet groups. Eight hour plasma fluoride profiles were then studied after ingestion of weighed quantity of test diets and means calculated. The bioavailability of fluoride from these diets was evaluated in relation to that of sodium fluoride in solution form. The amount of fluoride estimated in different test diets varied between 1.53 - 10.0 mg. The bioavailability was found to be 1.6 per cent for north Indian vegetarian diet, 7.5 per cent for east Indian diet, 14.4 per cent for north Indian nonvegetarian diet and 31.7 per cent for south Indian diet, however, the amount of F(mg) absorbed in plasma from these diets was found to be low i.e. 0.06 mg, 0.75 mg, 0.72 mg and 0.48 mg respectively.