Jacob Christian Schaffer. In 1757 the evangelical pastor, J. Ch. Schaffer (we do not know if he was at the same time a dentist, or merely an amateur in odontology), wrote a little book[483] to disprove the existence of worms in decayed teeth, and to show the fallacy of believing that the supposed worms may be made to drop out by means of fumigations of henbane seeds. His book appeared, as a matter of fact, rather behind-hand, for in it Schaffer repeats in substance what Houllier had already said two centuries earlier, and after him various other authors, including Fauchard. At any rate, to coöperate in the complete destruction of error and in the diffusion of truth is always laudable. We feel, however, bound to add that in the very same year in which Schaffer’s pamphlet was published, Dufour, a Frenchman, described a worm that had been taken out of a decayed tooth, and called attention to the fact that it was altogether different from the “dental worms” described by Andry.[484]

Bourdet. An excellent book on dentistry[485] appeared in France in the year 1757, the work of Bourdet, a celebrated dentist and elegant writer, in whom the gifts of literary and scientific culture were coupled with a vast experience and a profound spirit of observation. His merits procured him the honor of being appointed dentist to the King.

This author condemns as harmful the use of hard substances (such as bone rings, etc.) that people are in the habit of putting into children’s hands during the period of the first dentition, in the idea that by pressing these objects between the gums, as children instinctively do, they cut their teeth more easily. As to emollients, he holds them to be completely useless, and prefers to all these remedies the use of lemon juice.

According to Bourdet, the teeth are so apt to decay, partly because of the frequent changes of temperature to which they are exposed, and partly because, differently from the bones, they are not provided with any protective organic covering.

In many cases of caries, Bourdet extracted the tooth, filled it with lead or gold leaf, and replanted it; but if, in extracting, the alveolus had been somewhat injured (a thing very likely to happen with the instruments of the period), he replanted the tooth immediately, to preserve the alveolus from the damaging action of the air, and carried out the stopping at a later time.

Even in certain cases of violent toothache not depending on caries, Bourdet luxated the tooth and replaced it in position directly. But as some dentists had accused him of having passed off as new an operation already made known by Mouton since the year 1746, Bourdet defended himself by saying that whilst Mouton only shook the tooth, raising it a little, simply to distend the nerve, he, instead, effected a complete luxation, in order altogether to interrupt the continuity of the nerve. Anyhow, this operation was not new, as it had already been recommended and practised by Peter Foreest, in the sixteenth century, and in an even more remote epoch by the Arabian surgeon Abulcasis.

Sometimes, when the permanent canine comes forth, it has not room enough, and therefore grows outward. In this case Bourdet extracts the first premolar; the canine then advances gradually of itself toward the space left by the extracted tooth, until it occupies its place exactly. He also counsels the extraction of the first premolar on the opposite side of the jaw, in order to preserve the perfect symmetry of the dental arch on both sides. When the arch formed by the jaws is too large and of an ugly appearance, Bourdet advises extracting the first upper and lower premolars, so that the maxillary arches may acquire a more regular form. In cases in which the defect of form exists only in the lower jaw, that is, in children who have protruding chins, Bourdet corrects this deformity by extracting the first lower molars shortly after their eruption, that is, toward seven years of age. In this manner, says the author, the lower jaw grows smaller and the deformity disappears. The inventor of this method, as Bourdet himself tells us, was the dentist Capuron.

Bourdet made prosthetic pieces, whose base, representing the gums and the alveoli, was made entirely of gold and covered over with flesh-colored enamel on the outside, so as to simulate the natural appearance of the gums; the teeth were adjusted into the artificial alveoli and fixed with small pins. At other times he made use of a single piece of hippopotamus tusk, in which he carved not only the base, but also the three back teeth on each side, whilst the ten front teeth were human teeth fixed to the base with rivets.

One of Bourdet’s principal merits is that of having brought artificial plates to perfection by fixing them not, as heretofore, to the opening of the palate or inside the nose, but by means of lateral clasps fitted to the teeth.