What is dental plaque? Dental plaque is like a "bacterial community" composed of different bacteria. These "communities" are usually located on the surface of teeth, between teeth or on the surface of dentures. But dental plaque is one of the important causes of dental caries, and many dental caries begin with dental plaque. So what? The first stage is the formation stage of the acquired membrane. According to dental experts, saliva glycoprotein in the mouth is a substance in saliva, and everyone's saliva contains this substance. When it comes into contact with teeth, it can adhere to the surface of enamel and form a film-like substance. This membrane is called acquired membrane. It provides a substrate for the initial adhesion of oral bacteria and creates conditions for the formation of dental plaque. It has been proved that the gingival sulcus is the first place to form an acquired membrane on teeth. The second stage is bacterial attachment. Most researchers believe that acquired membrane is of great significance to bacterial adhesion. It was observed that when the acquired film was formed on the tooth surface, bacteria would attach quickly, indicating that the attachment speed was very fast. A large number of research data confirmed that the first bacteria attached to the tooth surface were Streptococcus sanguis and Streptococcus salivarius. Bacteria grow on the surface of acquired membrane and can produce acid. Glycoprotein deposition. Streptococcus sanguis and Streptococcus mutans can synthesize dextran and form plaque matrix together with deposited glycoprotein, which creates the foundation for plaque formation. The third stage of maturity. Bacteria grow, develop, reproduce and die on the acquired membrane, and carry out complex metabolic activities in it.