Time of a Dentist
Unfortunately, there's no over-the-counter treatment for cankers.
There are some things you can use to numb the pain, but they don't speed the healing. Your dentist, however, can use a laser
to instantly stop the pain permanently (although the healing still takes just as long). There is also a medication your dentist can use to stop the pain. In all cases, healing usually takes about 12 days.