Microflora is any living organism that requires a microscope to observe. Oral microflora is the flora that lives in a mouth. There are over 700 bacterial species that have been discovered to live in a mouth. When bacteria coat teeth, it is called biofilm or plague.
Oral bacteria are not all bad, but many have been linked to causing gum disease and other oral health issues. It also can be an indicator of other serious health threats.
Two main species of bacteria that are found in the mouth and can lead to other diseases or infections in the mouth are Streptococcus and Porphyromonas gingivalis. Both have also been found to produce acidic substances that can eat away teeth protection.