Our historical survey has now reached the end of the seventeenth century. Embracing at a glance the whole of this last period of time, we remark, among many facts of minor importance, some events which, in the history of the development of dental art, stand out in strong relief. Such are the replantation of teeth used as a special curative method by Dupont and others; the method of plugging in cases of alveolar hemorrhage, the credit of which is due to Rivière and to Tulpius; the description of the maxillary sinus given by Highmore; the rational treatment of affections of the antrum, inaugurated by Meibom, Cowper, and Drake; the researches into the microscopic structure of the teeth, brilliantly initiated by Leeuwenhoek, who discovered the dentinal tubuli; the use of models introduced by Purmann into the workmanship of prosthetic pieces; the employment of hippopotamus’ tusks in making artificial teeth, first recommended by Nuck; and the invention of Guillemeau, which was the first step toward the use of mineral teeth. [Illustration: Lorenz Heister.] CHAPTER XII. THE EIGHTEENTH CENTURY. Although there have been, even from the most remote times, individuals who have dedicated themselves exclusively to the cure of dental maladies, or to repairing the losses of the dental system by artificial means, and notwithstanding the progress gradually accomplished in this branch of the medical art, which progress was especially remarkable during the sixteenth and seventeenth centuries, it is not to be denied that, up to the beginning of the eighteenth century, dentistry was, in great part, considered one with medicine and surgery in general. It is but natural that dental art (and the same may be said of every special branch of medicine) could not assume a real individuality until it had attained to the higher grades of its development. As a matter of fact, dentistry, toward the end of the seventeenth century, was already a true specialty, although it counted but few worthy representatives at that time. The definite separation between the science and art of dentistry and general medicine and surgery, although it may have been retarded, could not fail to take place; and this, as we shall presently see, was effected by the celebrated French dentist Pierre Fauchard. But, to remain faithful to chronological order, we will first speak briefly of some other writers.