How to brush your teeth in space

I stumbled upon this cool video of Chris Hadfield, a Canadian astronaut, brushing his teeth in space. This is probably the most watched video on toothbrushing.

As a dentist, some things bug me about the way he brushes his teeth. I would expect that astronauts get training in how to brush their teeth...

Here are the improvements to the way he brushes his teeth.

  1. Get a better toothbrush! His flat toothbrush is not as effective as a well designed one. The more expensive brushes will be able to clean the intricate shapes of teeth much better.
  2. Keep the brush dry. Wetting the toothbrush will only dilute the toothpaste. The toothpaste will stick to a dry brush. There is no benefit to wetting it.
  3. Be systematic in where you brush. If you see in the video, Chris is jumping from place to place, oftentimes brushing the same places multiple times. He really likes to brush the outer surfaces of his teeth but barely brushes the surfaces on the tongue side. Jumping around is not time efficient and will inevitably lead to places not brushed well. Think about how you would wash a car. You wouldn't wash a bit of the bonnet then suddenly run to the boot and wash that. You would make your way gradually around the car.
  4. Be gentle. He is really rough with his brushing. This will cause teeth wear and gum recession. Small movements with gentle (not feather light) pressure is enough and allows the bristles to clean the tight spots much better.
  5. Aim to brush for 2 minutes. He suggested to brush in the time it takes to sing happy birthday. That song only lasts 15 seconds! The length of time he brushes in the video is appropriate so he is probably singing the song VERY slowly, or happy birthday has more verses than I know; just like the Australian national anthem.

Swallowing the toothpaste is fine, but spitting it out would be preferred. There is no benefit in swallowing it. If I was in space, I'd probably swallow it too. But I'm not! So spit it out. And what about flossing?!