Chauliac is particularly emphatic in his insistence on not permitting alimentary materials to remain in the cavities, and suggests that if cavities between the teeth tend to retain food material they should even be filled in such a way as to prevent these accumulations. His directions for cleansing the teeth were rather detailed. His favourite treatment for wounds was wine, and he knew that he succeeded by means of it in securing union by first intention. It is not surprising, then, to find that he recommends rinsing of the mouth with wine as a precaution against dental decay. A vinous decoction of wild mint and of pepper he considered particularly beneficial, though he thought that dentifrices, either powder or liquid, should also be used. He seems to recommend the powder dentifrices as more efficacious. His favourite prescription for a tooth-powder, while more elaborate, resembles to such an extent at least, some, if not indeed most, of those that are used at the present time, that it seems worth while giving his directions for it. He took equal parts of cuttle-bones, small white seashells, pumice-stone, burnt stag's horn, nitre, alum, rock salt, burnt roots of iris, aristolochia, and reeds. All of these substances should be carefully reduced to powder and then mixed. His favourite liquid dentifrice contained the following ingredients: Half a pound each of sal ammoniac and rock salt, and a quarter of a pound of saccharin alum. All these were to be reduced to powder and placed in a glass alembic and dissolved. The teeth should be rubbed with it, using a little scarlet cloth for the purpose. Just why this particular colour of cleansing cloth was recommended is not quite clear. He recognized, however, that cleansing of the teeth properly often became impossible by any scrubbing method, no matter what the dentifrice used, because of the presence of what he called hardened limosity or limyness (_limosité endurcie_). When that condition is present he suggests the use of rasps and spatumina and other instrumental means very similar to those we make use of for removing tartar. Guy de Chauliac was also interested in mechanical dentistry and the artificial replacement of lost teeth; and, indeed, dental prosthesis represents, as treated by him, a distinct anticipation of dental procedures usually thought quite modern.