Your parents probably taught you how to brush your teeth when you were just a toddler. Chances are, your method hasn't changed much over the years.
But is it the correct way? You might be surprised to learn that hardly anyone agrees.
Researchers at University College London (UCL) have consulted all the authorities, from dentists to dental associations. They even asked toothpaste companies what is the correct way to brush teeth.
The answers were not consistent. In fact, the researchers say they were “unacceptably inconsistent.”
The researchers say they even consulted dental textbooks and found no clear consensus between the various sources about how to brush and how long to brush. It's not a trivial matter, they insist.
"The public needs to have sound information on the best method to brush their teeth," said Aubrey Sheiham, senior author of the study. "If people hear one thing from a dental association, another from a toothbrush company and something else from their dentist, no wonder they are confused about how to brush.”
In the U.S., the American Dental Association (ADA) offers these guidelines:
- Place your toothbrush at a 45-degree angle to the gums.
- Gently move the brush back and forth in short (tooth-wide) strokes.
- Brush the outer surfaces, the inner surfaces, and the chewing surfaces of the teeth.
- To clean the inside surfaces of the front teeth, tilt the brush vertically and make several up-and-down strokes.
- Brush your tongue to remove bacteria and keep your breath fresh.
Twice a day
Britain's National Health Service says you should brush twice a day for 2 minutes at a time. As for when you should brush, NHS recommends just before bedtime and any other time during the day – just not right after a meal.
“Never brush your teeth straight after a meal as it can damage your teeth. This is especially important if you've had fruit, fizzy drinks, wine or any other food that contains acid because tooth enamel is softened by the acid and can be worn away by brushing,” NHS advises.
"Dental associations need to be consistent about what method to recommend, based on how effective the method is,” Sheiham said. “Most worryingly, the methods recommended by dental associations are not the same as the best ones mentioned in dental textbooks. There is no evidence to suggest that complicated techniques are any better than a simple gentle scrub."
Narrowing it down
What method to the researchers favor? They point to what they say is the most commonly-recommended technique – gently jiggling the brush back and forth in small motions, with the intention of shaking loose any food particles, plaque and bacteria. However, they note that no large-scale study has ever shown this method to be any more effective than basic scrubbing.
Sheiham, meanwhile, favors the brushing method advocated by the ADA.
"To avoid brushing too hard, hold the brush with a pencil grip rather than a fist,” Sheiham said. “This simple method is perfectly effective at keeping your gums healthy.”
Sheiham also says there is little use in brushing after eating sweets or sugary drinks because it won't prevent tooth decay. It takes bacteria from food about two minutes to start producing acid, so if you brush your teeth a few minutes after eating sugary foods, the acid will have already damaged the enamel.