求翻译：　　但需要注意的是，接吻虽然可以改善口腔环境，但前提是要注意个人口腔卫生，避免两人口腔之间细菌交叉感染，增加牙周病的发生几率。是什么意思？

　　But it is important to note, while kissing can improve oral environment, but the premise is to observe good personal oral hygiene to avoid cross-infection between two human oral bacteria, increasing the incidence of periodontal disease.