Charcoal is a powder made from wood, coconut shells, and other natural ingredients. It is added to toothpaste as activated charcoal, which may help remove extrinsic stains from enamel due to its mildly abrasive nature. Extrinsic stains are located on the enamel surface and are caused by the consumption of certain foods and beverages. However, because of its abrasiveness, routine use of charcoal toothpaste may harm the enamel, leading to enamel wear. Over time, this can make the teeth appear yellower, as thinning enamel reduces its translucency. Additionally, enamel wear can increase tooth sensitivity to hot and cold stimuli.

Charcoal is ineffective in removing intrinsic stains, which are located beneath the enamel. These stains can result from overexposure to fluoride, the use of tetracycline during pregnancy or tooth development, trauma to a tooth, or root canal therapy (RCT). Activated charcoal does not eliminate intrinsic stains