Precautions For Using Toothbrush

It is recommended to replace the toothbrush every three months to make the tooth cavity clean and less abraded. Regarding toothbrushes, there is another saying that is often mentioned: "Replace every 3 months." This statement is based on the fact that after a period of use, the toothbrush bristles will be curled and damaged, and the cleaning ability of such old toothbrushes will deteriorate, and the health and hygiene of the teeth cannot be well protected. The three-month time limit is based on the damage of most people's toothbrushes.

There is a certain basis for this statement in the early stage. An article published in the "Journal of Clinical Periodontology" in 1986 studied the issue of "whether the old toothbrush is not effective in removing plaque". One group of volunteers did not change toothbrushes for 10 consecutive weeks; the other group of volunteers changed toothbrushes every 2 weeks. After 10 weeks, the researchers compared their gum condition and the amount of plaque. It was found that the number of plaque on the teeth of the first group of volunteers was significantly higher than that of the latter group of volunteers. There was no difference in the condition of the gums between the two groups. It seems that an old toothbrush is indeed inferior in removing plaque. Experiments also show that there is such a big difference between people. Some people’s toothbrushes are horrible after only 2 weeks of use; some look good after 10 weeks of use.

However, as the investigation deepened, the Rumor Smasher investigators found surprising follow-up research. In 1996, another article also published in the "Journal of Clinical Periodontology" discussed this issue again. This time, the researcher's experimental protocol is slightly different from the previous one. They compared the conditions of dental plaque at different stages of the same test subject using the same toothbrush. The experiment lasted for 9 weeks, with every 3 weeks as a stage. As toothbrush wear intensifies, the amount of dental plaque has decreased. Similarly, for different people, the wear of the toothbrush after the same time is also different. Even if the volunteers were divided into two groups, "severe" and "slight" according to their toothbrush wear, there was no obvious difference in the ability to remove dental plaque between the groups. The conclusion of various experiments is that the old toothbrush is not inferior in effectively controlling the formation of dental plaque.

Similar conclusions were further verified in two studies in 2000 and 2002. Although the experimental protocols are different, both studies examined the effectiveness of toothbrushes used for 3 months and new toothbrushes in removing plaque. The conclusion is also "there is no significant difference." A study published in the Journal of Dental Research in 2006 used children (7, 8 years old) as the object of investigation. The researchers also found that there was no statistical difference between the 14-week toothbrush and the new toothbrush in removing plaque.

Conclusion: There may indeed be many microorganisms on toothbrushes, and clinical evidence does not believe that this poses a major threat to our health. However, keeping the toothbrush as clean as possible is something that should be paid daily. As for the claim that the toothbrush should be changed every three months, the research results do not support this claim.