My short answer is : Brushing your tooth without toothpaste will not cause a greater amount of micro-scratches than if you were to use toothpaste.
To begin, tooth paste, is a product most often made of abrasive substances that increases the scrubbing power of the toothbrush bristles. Some kinds of toothpaste can also accomplish other things, such as ...
The previous answer does not refer to clinical studies so I thought I would have a look.
TLDR; the clinical studies I've seen suggest not to rinse with water after brushing.
According to Doméjean, et al. (2018), you should not rinse after brushing.
For maximizing the topical effect of the fluoride toothpaste, patients should be encouraged to spit out ...
From a medical/dental standpoint, flossing and brushing with or without toothpaste is the best way of eliminating plaque, which can cause cavities and gum disease.
For the philosophical aspect of your question:
If you had to chose between the two (and you should be doing both!), I would floss, since floss reaches more easily between the teeth than the ...
Short answer: No. Using water, mouth rince, floss, toothpics or other means of removing debris between teeth should not cause dental movement.
Long answer: To cause dental movement, a continuous pression or pull has to be applied for many hours per day, over the span of weeks/months/years to make teeth move. That is why head gears have to be worn at least ...
Not rinsing after tooth brushing may somewhat increase the effectiveness of fluoridated toothpaste, but the evidence is inconsistent and the effect can vary greatly among individuals.
One possible explanation for inconsistent effect: not rinsing after brushing appears to be only beneficial if you are at a high risk of getting cavities.
I have never cleaned my teeth in bed or in space but both have a common problem - where to spit? Chris Hadfield made a video while on the ISS and said "swallow": https://youtu.be/M-Vqe1NGSKw?t=112 It is reasonable to assume his advice has come from NASA's medical team and is trustworthy and safe.
Hydrogen peroxide is an oxidizing bleach. It reacts chemically with the types of molecules that contribute to color.
So, it doesn't really remove stains, nor does it coat anything, but it does make colorful things not-as-colorful, just like if you wash your white socks with chlorine bleach.