It might possibly be suggested that coming at this time Arculanus should rather be reckoned as a Maker of Medicine in the Renaissance than as belonging to the Middle Ages and its influences. His education, however, was entirely completed before the earliest date at which the Renaissance movement is usually said to begin, that is with the fall of Constantinople in 1452, and he was dead before the other date, that of the discovery of America in 1492, which the Germans have in recent years come to set down as the end of the Middle Ages. Besides, what he has to say about dentistry occurs in typical medieval form. It is found in a commentary on Rhazes, written just about the middle of the fifteenth century. In the later true Renaissance such a commentary would have been on a Greek author. In his commentary Arculanus touches on most of the features of medicine and surgery from the standpoint of his own experience as well as from what he knows of the writings of his predecessors and contemporaries. With the rest he has a series of chapters on diseases of the teeth. Guerini in his "History of Dentistry" says that "this subject [dentistry] is treated rather fully, and with great accuracy." Even some short references to it will, I think, demonstrate this rather readily.[29] Arculanus is particularly full in his directions for the preservation of the teeth. We are rather prone to think that prophylaxis is comparatively a modern idea, and that most of the principles of conservation of human tissues and the prevention of deterioration and disease are distinctly modern. It needs only a little consideration of Arculanus' instruction in the matter of the teeth, however, to undo any such false impression. For obvious reasons I prefer to quote Guerini's summation of this medieval student of dentistry's rules for dental hygiene: