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Is there evidence that suggests that your teeth will be more healthy if you brush them multiple times per day than when you brush them once per day?

Christian
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  • related: [Does the claim that water fluoridation causes fluorosis have sufficient research support to be taken seriously?](http://skeptics.stackexchange.com/questions/133/) – Borror0 Mar 13 '11 at 16:25
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    For what it's worth, Richard Feynman was a [tooth brushing skeptic (first 18 seconds of this interview -- Take the world from another point of view)](http://www.youtube.com/watch?v=PsgBtOVzHKI), but it's also said by Gell Mann that he had terrible teeth because he never brushed them. – Jerry Asher Mar 13 '11 at 22:39
  • I, too, wanted evidence. I found some. Here you go: [Why brush for 2 minutes?](http://www.ncbi.nlm.nih.gov/pubmed/19723429) [How people tend to overestimate their brushing durations](http://www.ncbi.nlm.nih.gov/pubmed/10518854). –  Jun 24 '14 at 01:25

1 Answers1

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As with just about any instance regarding human physiology/biology: It depends.

Brushing has been shown to remove food particles that will lead to decay. However, brushing can also damage your teeth and gums if you use a brush that has stiff bristles, or brush too vigorously.

The general consensus from dentists seems to indicate that you should gently brush after eating. Although toothpaste is not required for all sessions. And if you have eaten anything acidic, it is best to wait.

According to Peter Heasman, a professor of periodontology at Newcastle University’s School of Dental Sciences, two minutes twice a day brushing with a pressure of 150 grams – equivalent to holding an orange – is correct practice.

In addition, regular dental care (and the associated benefits that are well documented by the entire field of dentistry) can lead to better heart health.

Laurel
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Larian LeQuella
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    Ideally I would want something evidence-based instead of a description of the advice that different authorities give. – Christian Mar 13 '11 at 15:46
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    I would contend that the entire field of dentistry is the evidence. I'm sure you wouldn't need a citation to say that jamming an ice pick through your head hurts or is a bad idea? Dental care has come to that same level of "obviousness". The areas where good advice can be given are the ones cited in the answer (i.e. proper procedure and timing). – Larian LeQuella Mar 13 '11 at 17:41
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    Lecturing directly of the important of evidence-based would mean for me to step a bit out of character. That leaves me with pointing out the conflict of interest: The dentistry industry makes money by selling various products. Few dentists run their business on a model where they would profit if their patients had good teeth. Given that conflict of interest it's important that dentists provide evidence for their claims. – Christian Mar 13 '11 at 20:28
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    The literature is available at any website that shows how food particles allow bacteria to deposit sugars on your teeth and that sugars and bacteria waste are bad for your enamel. Not to mention the enzymes in your saliva that start the digestion process also working away at the food particles on your teeth. While I hate the saying "common sense", this is really a case for that. Give bacteria food and a pleasant environment, they will multiply and leave waste and do their thing. – Larian LeQuella Mar 14 '11 at 01:08
  • I don't think that common sense theory is very good at explaining why some people have more problems with their teeth than others while they spend an equal amount of effort with brushing their teeth. Brushing your teeth could possibly disturb some innate defense mechanism of the body. Given that other defense mechanisms such as RNA interfere just got discovered in the last decade it's not clear that we know the way the body defends itself naturally against caries. – Christian Mar 14 '11 at 10:40
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    @Christian "has been shown" refers to evidence, not advice. "I don't think that common sense theory is very good at explaining" Yeah, because crackpotism is so much better. But hey, give up brushing altogether and see how you fare. After all, if there's no reason to think that brushing more than once a day improves health, then one can infer that there's no evidence that doing so even once a day does. Of course, the contrapositive holds -- the evidence that brushing *ever* improves health inferentially leads to brushing after every meal -- because, see, we *know the mechanism* of tooth decay. – Jim Balter Mar 17 '11 at 04:06
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    @Christian "Given that conflict of interest it's important that dentists provide evidence for their claims." Then go ask dentists, not here. The fact is that dentists have provided plenty of evidence, regardless of your own ignorance of it. – Jim Balter Mar 17 '11 at 04:08
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    @Jim: Without a controlled trial, I don't think that there evidence. Larian didn't refer to a controlled trial but think dentistry doesn't have to play by the rule book of evidence-based medicine. I would be even happy with a trial that isn't placebo controlled. – Christian Mar 17 '11 at 11:28
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    @Christian Who says there aren't controlled trials? – Jim Balter Mar 17 '11 at 13:35
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    @Jim: This answer doesn't refer to any controlled trials. This community has a standard that answers should be backed up by evidence. The burden of showing evidence is with the person who posts an answer. Larian argues that he fulfills his burden by pointing out by making an argument by authority. Controlled trials aren't necessary because it's common sense that brushing your teeth works. – Christian Mar 17 '11 at 14:03
  • @Jim please don't insult other posters, I've edited your comment – Mad Scientist Mar 17 '11 at 14:34
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    @Christian "This answer doesn't refer to any controlled trials." **You** wrote "Without a controlled trial, I don't think that there evidence", but there **are** controlled trials, so your statement is moot and your conclusion of no evidence is unsupported, as is your claim about what Larian thinks. As for "argument from authority", it's only a fallacy if the authority is inappropriate. By your lights any citation of a scientific work would be an argument from authority. And your claims of conflict of interest are unsupported. So much for adhering to community standards. – Jim Balter Apr 26 '11 at 21:20
  • This answer is highly misleading. It refers to a random dentist's website as the "general consensus". The statement "Although toothpaste is not required for all sessions." seems especially dubious. Note that dentistry is full of treatments that are not evidence based. (E.g. flossing https://medicalsciences.stackexchange.com/questions/12320/is-dental-floss-really-effective-according-to-studies-it-is-not). However, there is one preventative procedure that has strong evidence: The application of Fluoride (through toothpaste, drinking water, ...). Evidence linked in the following comment ... – Kvothe Jul 05 '21 at 11:46
  • https://www.cochrane.org/CD010856/ORAL_water-fluoridation-prevent-tooth-decay, https://www.cochranelibrary.com/cdsr/doi/10.1002/14651858.CD007868.pub3/full, https://www.cochrane.org/CD002278/ORAL_fluoride-toothpastes-preventing-dental-caries-children-and-adolescents – Kvothe Jul 05 '21 at 11:47
  • For an easy read on the issue of non-evidence-based measures in dentistry look at this news article https://www.nytimes.com/2016/08/30/upshot/surprisingly-little-evidence-for-the-usual-wisdom-about-teeth.html. – Kvothe Jul 05 '21 at 11:55