Microbiology
Microbiology (from Greek , "mīkros", "small"; , "bios", "life"; and , "-logia") is the study of microorganisms, those being unicellular (single cell), multicellular (cell colony), or acellular (lacking cells). Microbiology encompasses numerous sub-disciplines including virology, parasitology, mycology and bacteriology.
Oral ecology
Oral ecology refers to the organisms that live in a mouth. Bacteria in biofilm were first detected under the microscopes of Antony van Leeuwenhoek in the 17th century. Various bacteria and saliva are two of the major components in oral microbiology, having the capability to be harmful, but also performing beneficial and necessary roles in the immune system. Proper oral hygiene aims to control the harmful effects and prevent disease transmission.