Grattage. a method of drawing by scratching paper or cardboard that has been covered with india ink with a pen or a sharp instrument. The grattage process is reminiscent of scraping an oiled surface in lithography.rattage. a method of drawing by scratching paper or cardboard that has been covered with india ink with a pen or a sharp instrument. The grattage process is reminiscent of scraping an oiled surface in lithography.
3. (Zoology) of or relating to the surface of an animal, such as a jellyfish, on which the mouth is situated. 4. (Medicine) denoting a drug to be taken by mouth Compare parenteral: an oral contraceptive.
Oral microbiology is the study of the microorganisms (microbiota) of the oral cavity and their interactions between oral microorganisms or with the host. The environment present in the human mouth allows the growth of characteristic microorganisms found there.