This product is a solution composed of: 390 mg / ml 9nm silver nanoparticles ;21 mg / ml chitosan ; 22 mg / ml NaF.The cariostatic agent, nanosilver fluoride, was formulated in a similar way to silver diamine fluoride, so that this new formulation contained 5% nanosilver fluoride, while commercial diamine silver fluoride contains 30% silver fluoride. It will be applied once with a microbrush on tooth surfaces to check if it prevents the growth of S. mutans biofilms on dental surfaces.

The product will be applied in the volunteers in the morning, before the first class, in relative isolation, made with cotton rolls and Vaseline to protect the soft tissue. It will apply 30mg of the product with microbrush, previously standardized in a pilot study on cervical vestibular surfaces of incisors and canines healthy, on a total of 8 teeth, 4 upper and 4 lower. After a period of 7 days,the cervical dental biofilms will be collect, third on the buccal surfaces of incisors and / or canines upper and lower, with the aid of sterile spatulas.

The initial dental biofilm collection will be conducted to count colony-forming units of S. mutans and then the product will be applied on these dental surfaces after the collect. After one week, a new collect will be performed and the colony-forming units of S. mutans will be counting to compare with the initial.

Collection of dental biofilm will be performed after two weeks of product application and colony count will be performed in the laboratory.

Collection of dental biofilm will be performed after four weeks of product application and colony count will be performed in the laboratory.