what are toothbrush bristles made of

Most toothbrush bristles are made of nylon, a synthetic fiber that is strong, flexible, and hygienic. Nylon is used because it does not break down in water or with the types of ingredients usually found in toothpaste, and it is relatively affordable. Toothbrushes with alternative bristles may need to be replaced more often than toothbrushes with nylon bristles because other materials used in toothbrush bristles are not very resilient. While there are some eco-friendly alternatives to plastic toothbrushes, such as bamboo handles, most of them still use nylon bristles. Boar hair bristles are a natural alternative to nylon, but they tend to retain bacteria and are not suitable for vegetarians.