Hi Dear, welcome to HCM. Understanding your concern. Thanks for your query . Usually after healing of injury a mark is left behind . This is probable due to post inflammatory hyperpigmentation. The first and most important thing is to protect this mark from sun exposure to prevent it from further darkening. So apply sunscreen with SPF 15 in the day time . I would also suggest you to apply kojic acid cream at night which natural substance safe for long term use and is very effective in curing uch conditions . You can also apply this cream mix with vitamin E oil which will also be very beneficial . If condition persist after 1 month then you should consult dermatologist for proper examination . Doctor may recommend chemical peeling , or dermabrassion depending upon your condition. The cost of the procedure vary from place to place and depend upon various factor like severity of cut or mark , choice of method and how deep and in how any number of sittings the procedure will be performed . You can also apply turmeric paste mix with honey for ten minutes and wash away for at least month. Hope your concern has been resolved. Get Well Soon. Best wishes, Dr. Harry Maheshwari