Dental History

Teeth are hard, calcified structures embedded in the bone of the jaw that perform the function of chewing food. They are also necessary for pronunciation (f, v, th) and to maintain the shape of the face. An adult mouth contains 32 permanent teeth. A tooth consists of the crown (A1), the portion visible in the mouth, and one or more roots (A3) embedded in a gum socket. The gums (B5) cushion the teeth, while the jawbone firmly anchors the roots. The center of each tooth is filled with soft pulpy tissue containing blood vessels and nerves. Hard, bony dentin (B2) surrounds the pulp (B3) and makes up the bulk of the tooth. The root portion has an overlayer of cementum (B4), and the crown has a layer of enamel (B1), the hardest substance in the body.

There are four kinds of human teeth. An adult has 8 incisors (CD1), 4 canine teeth (CD2)--sometimes called eyeteeth or stomach teeth, 8 bicuspids (CD3)--also known as premolar teeth, and 12 molars (CD4) or grinders, including the wisdom teeth. Children have a set of 20 teeth--milkteeth--that fall out and are replaced by this set of 32 permanent teeth.

Modern dentists repair cavities (dental caries) by drilling them out, then filling them in with fillings, bonding, or resin. When teeth are beyond repair they pull them out and replace them with false teeth--a bridge, a plate, or a full set of dentures. The first metal dental fillings were installed by English surgeons way back in 1673.

But it wasn't until 1844 that Boston dentist Horace Wells pioneers anaesthesiology. after learning how to administer nitrous oxide ("laughing gas") from Gardner Colton. Wells first used it to deaden pain while extracting his own tooth. A year later he attempted to demonstrate use of the gas for a class at Harvard Medical School. His patient, however, was not completely anaesthetized when Wells pulled the tooth and thus failed to impress his audience.
Two years later another Boston dentist William Thomas Green Moton made a similar discovery. Unfamiliar with C. W. Long's 1842 ether discovery, he attended a lecture by chemist Charles T. Jackson and learned that inhaling sulfuric ether can cause a loss of consciousness. He tried the gas on himself and on his dog before using it to extract a tooth from a patient. News of the painless extraction was leaked to the newspapers, where Boston surgeon Henry Jacob Bigelow read about it. He then persuaded Morton to demonstrate his procedure at Massachusetts General Hospital when surgeon John Collins Warren used ether on a patient during an operation. Ether found immediate use in operations on Mexican War casualties, opening a new era in surgery as well as dentistry.

In 1875 Kalamazoo, Mich., inventor George F. Green patented an electric dental drill. He assigned his patent on "electro-magnetic dental tools" for sawing, filing, dressing, and polishing teeth to Samuel S. White of Philadelphia whose company became the leading U.S. producer of dental equipment, but use of electric drills had to wait for the development of lighter engines and less expensive batteries.

In 1945 a fluoridation program at Grand Rapids, Mich. was the first attempt to fluoridate community water supplies in order to reduce the number of cavities in children. A similar plan in Newburgh, N.Y., follows aroused wide-spread opposition