Paris being at that time in full revolution, Dubois de Chemant was induced to emigrate to England. He established himself in London, and there obtained a patent without much difficulty, according him the exclusive right, for fourteen years, of manufacturing dentures of mineral paste.
Dubois de Chemant wrote several pamphlets in order to make known to the public this new kind of dental prosthesis and its advantages; some of these were published in Paris (1788, 1790, 1824), and others during his long residence in London, where he remained from 1792 to 1817. In these pamphlets he upholds the great superiority of “the incorruptible teeth of mineral paste” over all other kinds of artificial teeth; he calls special attention to the fact that teeth of bone, ivory, and of every other organic substance whatever gradually become spoilt through the action of the saliva, of oral heat, of food and drink, etc., and not only lose their primitive color and assume a dirty hue, most unpleasant to the eye, but acquire a bad odor, at times quite insupportable, becoming, besides, a cause of irritation to the gums and the mucous membrane of the mouth, not to speak of their gradual softening and wearing out, which renders them unserviceable after a certain time. All these disadvantages were avoided by using the new prosthetic material, this being incorruptible and inalterable.
The prosthetic appliances by Dubois de Chemant were made in one single piece that represented the gums and teeth, whether in the case of one or more teeth, or of whole dental sets. He used to take a cast of the parts on which the prosthesis was to be applied, and by a process, the details of which are not known; he succeeded in obtaining prosthetic pieces that fitted the parts perfectly, notwithstanding the difficulties resulting from the shrinking of the paste in baking. If the piece required retouching, he did this by means of special tools for grinding down porcelain. He could, besides, drill holes in the porcelain for the application of the means of attachment. In fact, Dubois de Chemant was the creator of a new method of prosthesis applicable to any and every case, and which gained the praise and admiration of the great doctors and scientists of that day, among whom may be mentioned Geoffroy, Vicq d’Asyr, Descemet, Bajet, Petit Radel, Darcet, Sabatier, Jenner, and others. The Paris Faculty of Medicine gave it as their judgment that the prosthetic pieces manufactured by Dubois de Chemant united the qualities of beauty, solidity, and comfort to the exigencies of hygiene.
These eulogies must, however, be received with a certain reserve, as, beyond doubt, the mineral teeth of that time still left much to be desired. In England, where, as we have already said, they had been introduced by the inventor, they at first obtained a great success, which was, however, of short duration, and Maury[547] tells us that toward 1814 they had fallen into great discredit and had been entirely abandoned; this signifies that practically they did not fulfil the expectations held out.
Dubois Foucou and Fonzi. Among the first who occupied themselves with the manufacturing of mineral teeth, contributing also to their improvement, are to be named Dubois Foucou, to whom we have already made reference, and Fonzi, an Italian by birth, who exercised the profession of dentist in Paris. Dubois Foucou made some improvements in the coloring of porcelain teeth, and in 1808 published a pamphlet in which he explained his mode of proceeding in manufacturing them.[548] In the same year Fonzi made known a new kind of teeth,[549] which he called terro-metallic. These differed from those of Dubois de Chemant in that they were all single teeth intended to be applied on a base by means of small hooks of platina, with which each tooth was furnished. In addition to this important innovation, Fonzi also discovered the means of imitating in some degree the semitransparent tint peculiar to natural teeth.
Notwithstanding this, the teeth made by Fonzi, of which there are still some specimens in various dental museums, had anything but a good appearance, and there still remained much to be done before mineral teeth reached the height of perfection which they attained later on.
