From time to time, you may feel some general soreness in your gums or irritation due to the braces or Invisalign aligners. Rinsing your mouth with warm salt water or taking Tylenol will help ease the discomfort. But rest assured that in a few days this discomfort will ease.
Also for those with braces, the tooth-side surface of your lips and cheeks may become irritated for a while as they become accustomed to rubbing on your braces. If this happens, brace wax can be applied to the braces to ease the irritation.