| OraMedia - Dental Self Sufficiency |
 | Startling information to root canal alternatives and common sense information on proper, in-home oral health. Interesting reading for any fitness fan, sportster and lover of healthy lifestyles; especially useful for those like pilots and explorers, who need to pay special attention to their own health. Curiously, the material from which teeth are actually made, known as dentine, has been found in the scales of ancient fishes that did not even had jaws and neither they had teeth, for there were no use for teeth without a jaw, right? The first fishes appeared during the Cambrian period, a little more than five hundred million years ago. These fishes belonged to a class known today as 'Agnatha' from which just two species remain today: the lamprey and the hagfish. All other species belonging to this class have long disappeared. But after a few million years their first appearance, agnathans diversified quite a bit. In all cases known to us, the fishes belonging to this class that evolved during the Silurian and Devonian periods ate by aspiring plankton and algae into their mouths, which were essentially holes in their heads with no other functionality. Among the agnathans, a new order of fishes appear during that time, know as 'Thelodonti,' and these, generally small fishes have proven to be curious for one reason, which is that their scales, which evolved long before jaws and consequently teeth were naturally developed as evolution progressed, were made of the same material from which teeth grow, and the internal structure of each little scale they had covering their skin strikingly resembles a tooth, for they even have pulp cavities. 'Phlebolepis' is a thelodont fish, about 6 cm long from which good fossil remains have been found, covered with these little scales resembling teeth. Thus, it is valid to speculate that as jaws evolved from the anterior gill openings that these fish had, the skin and scales surrounding the rim of each gill suffered also some adaptations, becoming later the gum and teeth in the mouths found on most animals. So, probably, the next time you look at your teeth, you will be looking at what is left in you of your distant fish relatives! |
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