Hi Dear, Welcome to HCM. Understanding your concern. Thanks for your query .There can be many factors that can cause black spot on gum like deposition of plaque on gum cause black patch ,it can bruise.hyper pigmented patch,amalgam tattoo (if you have any silver filling) or can be a serious condition like malignant melanoma(rare ).Some medication can also cause black spot on gum like antidepressants. I would suggest you to maintain proper oral hygiene by brushing and flossing teeth twice a day.Usually they do no cause any harm ,but if they affect your appearance then consult a doctor to rule out some serious condition and explore various treatment options available like laser and bleaching treatment . What you can do now is apply vitamin E oil at night and do hydrogen peroxide rinses diluted with 3 parts of water. Hope your concern has been resolved. Get Well Soon. Best Wishes, Dr. Harry Maheshwari