Bamboo toothbrushes are similar to any other manual toothbrush you would find on the shelf. They have a handle and bristles to remove food bits and plaque from your teeth. The key difference between bamboo toothbrushes and plastic toothbrushes is the material used to make the handle.
Although bamboo toothbrushes may seem like a new, eco-friendly item, they are actually one of the oldest types of toothbrushes. As the Library of Congress points out, the earliest bristle toothbrushes were invented in China in the 15th century and featured boar hair bristles and bamboo handles.
While you're more likely to find nylon bristles on modern bamboo toothbrushes, some still do have bristles made from boar hair. Others have bristles infused with activated charcoal, which may help whiten teeth.
When choosing a toothbrush material, consider how bamboo differs from plastic and wood. Bamboo plants grow quickly, need little care and may thrive without fertilizer or pesticides.
When used in its raw form, such as in the shape of a toothbrush handle, bamboo does have a considerably smaller ecological footprint compared to plastic. This is because bamboo is biodegradable. You can compost the handles of bamboo toothbrushes if you first remove the nylon bristles. You can also find ways to creatively reuse the toothbrush handles, such as turning them into plant markers for your garden. However, if bamboo toothbrushes end up in the trash, they aren't significantly more environmentally friendly than their plastic cousins.
If you want a fully biodegradable toothbrush, choose one with a bamboo handle and bristles made from boar hair. Keep in mind that boar hair bristles tend to be rougher than nylon ones, and hard bristles can cause wear on your enamel and contribute to receding gums.