Toothbrushes are about 5,000 years old. Twigs, bones, wood, ivory and boar bristles form a long history of oral cleaning tools. The nylon bristled toothbrush we use today was invented in 1938. sonic toothbrush are also common these days. Both manual and sonic toothbrush are effective and thorough in

I saw a lot of great god described extremely extensive, from the functioning concept of electric toothbrush to the day-to-day use of matters requiring attention, I wished to open the electrical toothbrush step by step to describe the production concept and process to me. I REALLY CAN't stand, the ne