The rGO-Ag NPs nanocomposite was synthesized by an easy, low-cost, one-step chemical method. The nanocomposite was analyzed by UV-Vis spectroscopy and atomic force microscope (AFM) to verify the properties of the nanoparticles. The study of the optical properties showed that there are two peaks, one of which belongs to silver and is 400 nm, and the other is related to graphene oxide at 268 nm. The AFM examination of the rGO-Ag NPs revealed that the average grain size is 71.26 nm, and this indicates that the material is within the nanoscale. The rGO-Ag NPs nanocomposite was applied as an antagonist against various types of bacteria that cause gum and tongue infections, and the results showed that with the increase in the nanocomposite concentration, the killing rate of bacteria increases. This means that the killing increases with increasing volumes of rGO-Ag NPs, and the best one is 40 μL. The result shows that the rGO-Ag NPs show a relationship between adding volumes of the nanomaterial and the percentage killing of bacteria, which is directly proportional. Additionally, through UV-Vis spectroscopy, the absorbance of the rGO-Ag NPs was determined, so that the laser with a wavelength of 405 nm was chosen to be applied to the same kinds of bacteria and for different periods of time with the use of a 40 μL volume of the rGO-Ag NPs, and it was found that with increasing the irradiation period, the percentage of bacteria killed increases. It showed that increasing the irradiation period with volume stability of 40 μL causes a higher killing rate. The study indicated that using nanocomposite and laser is a method to remove the infection from the gums and tongue. These results are promising and can be applied in the treatment of gum and tongue infections after clinical studies.