You probably wouldn’t think of carrying around a pen without ink, so why do we all carry around toothbrushes that we have to load up prior to use? This invention from Kawamura Ganjavian makes perfect sense: it’s a toothbrush with a toothpaste reservoir right in the handle.
When you’re going on a trip, you pre-load the reservoir with the appropriate number of toothpaste servings. Then, simply twist the handle to squeeze some paste onto the bristles and get to brushing.
Of course, you could also use the Twist & Brush when you aren’t on the road. The design is so simple and intuitive it’s hard to believe no one has thought of it before.