Dr. Cooper advises people to rinse their toothbrush under warm tap water “to remove any remaining toothpaste and debris” from the device. Storage is another important factor when keeping a brush clean from any bacterial growth. “Store it upright and allow it to air dry,” Dr. Cooper says. “That’s because if you store it upright and allow it to air dry, the bacteria should be eradicated in time for the next use.” A mistake people can make is placing their toothbrush in a closed container or cabinet that prevents the device from fully air drying after use. “The moist toothbrush in a closed, dark environment is more likely to give rise to the growth of unwanted bacteria than is likely to occur if a toothbrush dries in an open environment,” Dr. Cooper says. If someone wants to use their carrying case, it’s recommended to wrap the toothbrush in a paper towel to allow it to dry.