ARTIFICIAL DENTURES. Prior to the discovery of the method of making, porcelain teeth, the dentist made use of human teeth, animal teeth (those of cattle and sheep), hippopotamus tusks, elephant and other ivories, and bone. The human and animal teeth were fastened in the mouth by ligatures of gold or silver wire, un bleached thread, sea-grass, or silkworm gut. The hippopotamus or elephant ivory, or the common bone, was carved in single teeth or blocks, and perhaps in the shape of full or partial dentures, to replace the lost natural teeth. The objections to this method of restoration were the difficulty of getting accurate adaptation in the mouth. and the tendency. because of the porosity of the material, to absorb moisture, to become offensive, and ultimately to decay. The use of porcelain as a material for artificial teeth was first pro posed by Fauchard in 172S; but the manufacture of porcelain teeth was first actually begun by Duchateau. a French chemist, assisted by Du bois, a dentist of Paris, somewhere between 1774 and 1776. The date of the introduction of metal bases in prosthetic dentistry is not definitely known. It is believed, however, that gold was the first metal used as a base for artificial teeth, and that Dr. Cardette. of Philadelphia. was the first to use the gold base in this country, in or before 1787. Among the other metals which have been used as bases for artificial dentures are silver, platinum. aluminum, tin, and various metallic alloys; hut at the present time gold and platinum are the only metals in general use for that purpose. l;ntia perelur as a base was introduced in England by Edwin T•ueman, about Is5L I s;31, Goodyear discovered a method of making a hard rubber compound, since named and in 1855 Charles Good year, sirs, a patent in England for making a dental plate of hard rubber, in which the teeth were seen red before the compound a preparation of collo dion, was nest experimented with as a base. lout,
owing to the diffieulty of manipulating it, and to its lack of durability, it fell into disuse. Ce//a 1 old was the next material tried, but, being more porous and less durable than vulcanite, it is seldom used at present. Porcelain and a com bination of platinum and porcelain have liven used as bases for artificial dentures. Porcelain alone did not come into general use because of the diffi culty of manufacture, brittleness, and danger of shrinkage or warping during the process of tiring. The combination of pore, 4a in (11111 plat in um, (•ontinuous gun!) is made as follows: A base of platinum is swaged to tit the month, the arti ficial teeth are lined with metal and soldered to the platinum base; a porcelain body of the proper sh.ide is next molded about the necks and root portion of the artificial teeth, as well as upon the exposed surfaces of the platinum. and carved and colored to imitate the natural mucous membrane of the mouth; the entire piece is then put in an oven and baked long enough and often enough to fuse the porcelain properly. This method of inserting artificial teeth is one of the best at our command, so tar as beauty, cleanliness, durability, and correct imitation of nature are concerned.