Since toothbrushes are inanimate objects, you cannot kill them. However, you could break it, which would sort of be considered killing a toothbrush, but killing only applies to living things.
Many, many countries make toothbrushes.
nothing
Yes, peanut butter people can eat toothbrushes.
Toothbrushes for dogs come in a variety of colors. My dog's toothbrush is blue.
toothbrushes weren't invented then!
Any toothbrush is only as effective as the person using it. If used properly, most manual toothbrushes can adequately clean your mouth. I typically recommend electric toothbrushes to people who have some kind of physical limitation, such as arthritis.
It is difficult to provide an exact number, but it is estimated that there are billions of toothbrushes used around the world. This number is constantly changing as toothbrushes are manufactured, sold, and disposed of.
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It's not common but probably somewhere in the world it is possible, especially in countries where toothbrushes are in short supply.
The cast of Toothbrushes - 2011 includes: Nikos Branidis Kathryn Freytag
There are various companies that sell electric or battery operated toothbrushes also have oscillating heads. Some of the brands that have toothbrushes with an oscillating head are Oral B, Philips and Arm and Hammer.