The 2011-12 NHANES figures documented another 31% overall increase among American teens since the previous decade, with a total adolescent population impact of 61% afflicted. More than one in five American teens (23%) have moderate to severe dental fluorosis on at least two teeth. Mechanism
Teeth are the most studied body tissues to examine the impact of fluoride to human health. There are a few possible mechanisms that have been proposed. It is generally believed that the hypomineralization of affected enamel is mainly due to in-situ toxic effects of the fluoride on the ameloblasts in the enamel formation, and not caused by the general effects of fluoride on the calcium metabolism, or by the poisoning effects that suppress the fluoride metabolism. However, despite decades of research and studies, there have yet to be any studies that substantiates the believed mechanism whereby dental fluorosis is a result of alteration in the mineralisation that takes place when fluoride interacts with mineralising tissues.In the extra-cellular environment of maturing enamel, an excess of fluoride ions alters the rate at which enamel matrix proteins (amelogenin) are enzymatically broken down and the rate at which the subsequent breakdown products are removed. Fluoride may also indirectly alter the action of protease via a decrease in the availability of free calcium ions in the mineralization environment. This results in the formation of enamel with less mineralization.
Aponeurotic fibroma (also known as "Calcifying aponeurotic fibroma," and "Juvenile aponeurotic fibroma") is characterized by a lesion that usually presents as a painless, solitary, deep fibrous nodule, often adherent to tendon, fascia, or periosteum, on the hands and feet. The World Health Organization, 2020, reclassified aponeurotic fibroma nodules as a specific benign type of the fibroblastic and myofibroblastic tumors. See also
Skin lesion


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