toothpaste and toothbrush are definitely medical then, as a dentist definitely is in the field of medicine, and if you don't use them your teeth rot and fall out. oral-B is definitely a medical brand. "warding off disease" simply and clearly covers this, then. Thanks for the informative link.
I've heard this list other places too but don't have a source. The four requisites mentioned on that page are what I typically think of.