Sock it in normal/tap water for 7/8 hours or Keep the bristles under the hot water until they soften. Use your fingers to test the softness by gently rubbing them along the bristles. Once they feel soft to your touch, you can brush your teeth.
All bristles are safe,
Yes ,the bristles and the handles of toothbrush are made of the same material that is nylon.
The capitol of a toothbrush (most important part) is the bristles. Why am I answering this?
Nylon.
Yes ,the bristles and the handles of toothbrush are made of the same material that is nylon.
Helpful Friction.
I'm assuming that they are attached on a small board. I would expect the plastic of the toothbrush to be put over the board and the piece over the board would have holes to allow the bristles to come through the plastic.
No. The bristles of the brush will damage the soft tissue inside.
it stands for the stiffness of the bristles but the lower the number the softer or harder?
No
The Reach toothbrush is not actually a company but a brand of toothbrush. Johnson & Johnson created the Reach toothbrush in the 1980's. It differed from other toothbrushes of its time due to the angled head. Also, the bristles of the brush were closer together which allowed it to clean the teeth better.
about 2 or 3 months maybe. pretty much when the bristles start to spread out or when you lose them. Hope this helps! :D