Still, there will also be minimal bacterial fluid spillage, which is an unavoidable problem during the experiment; this experiment mainly studied the role of pro-inflammatory factors in the process of periodontitis causing MCI, and did not fully consider anti-inflammatory factors such as IL-10; finally, in the in situ hybridization results of the P. gingivalis + SB group, it can be seen that the amount of bacteria in brain tissue is less than that in the P. gingivalis group, and the specific mechanism of this result needs to be further studied. This evidence concerns the gene IL10 and periodontitis.