What's the best way to brush your teeth? Dentists disagree, and no one can say for sure, according to a new study.
"There's no good evidence at the moment that one method of brushing is more effective than another," Dr. John Wainwright, the study's lead author, told Reuters Health in an email.
"Ask more than one dentist or hygienist how to brush your teeth, and they're likely to give conflicting messages. It's confusing and potentially will make you wonder who you should trust to give you the best advice," he said.
Wainwright is a practicing dentist from University College London in England.
He and a colleague, Dr. Aubrey Sheiham, examined tooth-brushing recommendations in dental textbooks, from toothpaste and toothbrush companies and from dental associations in 10 countries. Most sources recommended twice-daily brushing for two minutes, they found.
But dental professionals failed to reach consensus about the preferred brushing method and remained divided about how often to brush and for how long.
"It's undermining faith and trust in the profession as a whole," Wainwright said.
Though a majority of sources advised brushing for two minutes, some recommended brushing for up to three minutes. One even recommended more than three minutes of brushing at each tooth cleaning.
Read: Keep your smile healthy
Dentists and dental associations recommend six different methods of manual tooth-brushing, the authors write in the British Dental Journal. The methods vary by toothbrush angles and preferred motions.
"A lot of different dental professionals advise different ways to brush your teeth," Wainwright said. "With the evidence currently available, a complex method may be no more useful than a simple scrub, which is a lot easier to learn."
We could be doing better
Dental epidemiologist Dr. Benjamin Chaffee said the research stirred a lively online discussion among dentists. Chaffee is a professor in the University of California, San Francisco, School of Dentistry and was not involved in the current study.
"There's a lot we could be doing better," he told Reuters Health.
"After 100 years of thinking about tooth-brushing, the profession hasn't been able to reach a consensus that has really strong evidence behind it. It's entirely plausible that there's no one technique that's superior," he said.
Chaffee and Wainwright agreed that the conflicting messages point to the need for evidence-based research into the most effective tooth-brushing method.
"For something most people do twice a day, you would expect dentists to send a clearer, more unified message to their patients on how to brush their teeth," Wainwright said.
He said he wanted to do the current study because his patients frequently ask him why his tooth-brushing recommendations differ from the last dental professional they saw.
In a statement, Sheiham suggested brushing "gently with a simple horizontal scrubbing motion, with the brush at a 45-degree angle to get to the dental plaque." Sheiham is an emeritus professor at University College London.
Read: Dental plaque may be a cancer risk
He said there is little point in brushing after eating sweets or sugary drinks because bacteria from food begin producing acid in about two minutes.
"So if you brush your teeth a few minutes after eating sugary foods," he said, "the acids will have damaged the enamel."
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Image: Man brushing teeth from Shutterstock
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