In celebration of the 50th anniversary of Neil Armstrong walking on the moon, we wondered, how exactly DO astronauts brush their teeth in space?
To start, the effects of gravity are much different in space.1 Something as simple as the cap to a tube of toothpaste could float away if not fixed in place. Water cannot fall from a faucet into a sink and instead forms droplets that float around the spacecraft.2 Likewise, it is not simple to spit when you are finished brushing.
Ingestible toothpaste was one solution to the problem of spitting and was developed by Dr. Ira Shannon of the Houston VA Medical Center.3 The product called NASAdent was a foamless toothpaste that could be swallowed.4 Research comparing NASAdent to commercially available toothpastes showed comparable cleaning ability and user acceptance. NASAdent had uses outside of space as well, including hospitals, nursing homes, and other special care facilities where excellent preventive dental care is important. While NASAdent may no longer be available, there are other ingestible toothpastes on the market that can help fill the very specific niche of edible toothpastes.5
Whether in space or on earth, the American Dental Association recommends brushing for two minutes twice per day.6 Today, astronauts use traditional toothpaste and toothbrushes to maintain excellent dental health as demonstrated by Col. Chris Hadfield while he was a commander of the International Space Station.7
1 Dunbar, Brian. “What Is Microgravity?” Edited by Sandra May, NASA, NASA, 16 June 2015, www.nasa.gov/audience/forstudents/5-8/features/nasa-knows/what-is-microgravity-58.html.
2 “Water Is a Sphere in Space.” Water in Space: How Does Water Behave in Outer Space?, USGS, www.usgs.gov/special-topic/water-science-school/science/water-space-how-does-water-behave-outer-space?qt-science_center_objects=0#qt-science_center_objects.
3 US Department of Veterans Affairs, et al. “A Brief History of the Houston Veterans Hospital and Its Research Program - Michael E. DeBakey VA Medical Center - Houston, Texas.” Michael E. DeBakey VA Medical Center - Houston, Texas, US Department of Veteran Affairs, 6 Sept. 2011, www.houston.va.gov/about/History_of_Research_Program.asp.
4 United States of America, NASA, Office of External Relations, and James J Haggerty. “Spinoff 1984.” Spinoff 1984, NASA, 1984, p. 62. ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/20020091883.pdf. Ingestible Toothpaste
5 Rubido, S., et al. “In Vivo Antiplaque Effect of Three Edible Toothpastes.” Medicina Oral Patología Oral y Cirugia Bucal, vol. 19, no. 1, Jan. 2014, pp. e88–e92., doi:10.4317/medoral.18973.
6 “Brushing Your Teeth.” Mouth Healthy, American Dental Association, 2019, www.mouthhealthy.org/en/az-topics/b/brushing-your-teeth.
7 “How To Brush Your Teeth In Space.” Performance by Chris Hadfield, YouTube, VideoFromSpace, 1 Apr. 2013, www.youtube.com/watch?v=TU9kffoAQ8U.