What is the term for the separation of wound edges with exposure of underlying tissues?

Mr. Santos, a 65-year-old male, underwent abdominal surgery for a perforated gastric ulcer. He developed a wound infection postoperatively and was started on antibiotic therapy. On the 5th Postoperative Day, Mr. Santos suddenly feels a “popping” sensation in his abdominal incision and the wound edges separate and revealing underlying tissues.