Encouraged by this success, he tried to manufacture like dentures for personages of high rank, hoping to gain money thereby, but his want of knowledge of the dental art prevented him from succeeding in his undertaking. However, in 1776 he laid this new process before the Royal Academy of Surgeons in Paris, receiving the thanks of that body as well as an honorable mention.
Whilst Duchâteau, discouraged by failure, was giving up all idea of deriving profit from the practical application of his invention, Dubois de Chemant, on the contrary, did not cease working for a moment, in order to bring the new method of prosthesis to perfection. Little by little he introduced important modifications into the composition of the mineral paste used in the manufacture of the dentures, incorporating therewith Fontainebleau sand, alicant soda, marl, red oxide of iron, and cobalt. His experiments and researches aimed at three principal ends, viz.:
1. The obtaining of mineral teeth offering all the gradations of color presented by natural ones.
2. The arriving at a rigorous calculation of the contraction of the mineral paste in the baking, so as to be able to make prosthetic pieces of the desired form and dimensions.
3. The perfecting of the means of attachment of the prosthetic pieces, and, in particular, of the springs.
By working with intelligence and perseverance, Dubois de Chemant gradually obtained satisfactory results, and when, in 1788, he published his first pamphlet on mineral teeth, he had already made dentures and partial prosthetic pieces for a certain number of persons, who wore them to great advantage.
As to the chemist Duchâteau, from 1776 to 1788, that is, during the twelve years subsequent to his communication to the Academy of Surgeons, he did absolutely nothing at all. He is, therefore, entitled to the credit of having had a happy idea and of having endeavored to put it into practice; but the merit of having given life to the idea, abandoned for so many years by him with whom it originated, is exclusively due to Dubois de Chemant; he is, therefore, with reason considered the true inventor of mineral teeth.
Dubois de Chemant, however, was so unjust as to take the whole credit of the invention for himself, declaring in his writings that the original idea had been exclusively his own, and was in no way due to Duchâteau.
In 1789 Dubois de Chemant made his invention known to the Academy of Sciences and to the Faculty of Medicine of Paris; both pronounced in favor of it, and in consequence of the opinion given by such high authorities, he soon after obtained an inventor’s patent from Louis XVI.
Dubois’ successes now aroused the envy of many of his colleagues, and especially of Dubois Foucou, the king’s dentist, who, together with the greater part of the dentists of Paris and the chemist Duchâteau, brought an action against him, accusing him of having usurped the invention of Duchâteau, and demanding, for this reason, the annulment of the inventor’s patent that had been granted him. But the law courts, in an opinion dated January 26, 1792, rejected the demand for annulment, recognized the patent of invention as fully valid, and condemned Dubois Foucou, Duchâteau, and their confederates to the costs of the judgment.