A patient asked recently if she could still use her charcoal toothpaste whilst she's having Invisalign treatment. I answered this with the same advice I always do when patients want to try out 'whitening' toothpastes.
There are no proven oral health benefits associated with the use of charcoal toothpaste.
It can actually damage the surface of your enamel as it is so abrasive.
If you want to whiten your teeth, use professional tooth whitening methods.
Use a fluoride toothpaste (1350ppmF) twice daily for brushing.
Avoid so called 'whitening' toothpastes. They tend to be more abrasive than normal toothpastes.