['The purpose of this study was to observe platelet aggregation promoted by biofilms of Streptococcus sanguinis and Porphyromonas gingivalis and to evaluate the effect of two different mouth rinses on this process.', 'In the first experiment, the same amount of S. sanguinis, P. gingivalis, and the S. sanguinis + P. gingivalis mixed solution was added to an equivalent amount of platelet-rich plasma (PRP). Aggregation was measured using a recording platelet aggregometer. In the second experiment, S. sanguinis, P. gingivalis, S sanguinis + P. gingivalis mixed solutions were pretreated with either Listerine antiseptic mouth rinse or Xipayi mouth rinse for 3 minutes, 6 minutes, and 10 minutes, respectively. The same amount of solution was added to the PRP, and the inhibition of aggregation was measured.', 'In the first experiment, S. sanguinis and P. gingivalis were able to induce platelet aggregation. The aggregation rate of S. sanguinis + P. gingivalis was significantly lower than that of either S. sanguinis or P. gingivalis. In the second experiment, when S. sanguinis, P. gingivalis, and the S. sanguinis + P. gingivalis mixed solutions were pretreated with Listerine antiseptic mouth rinse for 3 minutes and Xipayi mouth rinse for 10 minutes, there was no significant platelet aggregation.'] Does platelet aggregation promoted by biofilms of oral bacteria and the effect of mouth rinse in vitro?