Patients who have been screened by inclusion and exclusion criteria will be randomly (non-transparent envelope) assigned to Skin Stretching Group (SS Group) or Skin Grafting Group (SG Group). Patients of both group will undergo surgical debridement for the same principle, while the Skin Stretching Device is used for the patients of SS Group for incision closure and the Skin Grafting is used for the patients of SG group for incision closure.