美国俄克拉何马大学口腔病理教授汤姆·格拉斯博士对一批患感冒伤风或喉痛的病人进行了研究。他把病人分为两组,第一组在即将痊愈时更换了新牙刷,第二组不更换牙刷。结果显示:第一组病人康复时间比第二组要短得多,而且复发率较低。格拉斯断博士认为,经常处于潮湿状态的牙刷,刷毛之间的空隙是细菌和病毒生存滋长的最佳温 Dr. Tom Grasse, a professor of oral pathology at the University of Oklahoma in the United States, studied a group of patients with cold or sore throat. He divided the patients into two groups. The first group replaced the new toothbrush immediately after healed and the second did not change the toothbrush. The results showed that: the first group of patients recovery time is much shorter than the second group, and the recurrence rate is low. Grasse broken Dr., often in a damp toothbrush, the gap between the bristles is the best growth of bacteria and virus survival