Treatment for Indented Surgery Scar?

The atrophic nature of your scar is due to contraction of surgical scar. Filler injection to replenish the lost volume would be the best, instantly gratifying option for depressed scar particularly along tear trough areas. In the hands of an experienced board-certified dermatologist or plastic surgeon, a variety of fillers can be considered, e.g. Restylane, Juvederm, or Evolence Breeze.

It is quite common to heal after MOHS surgery without sutures.  Actually in some places on the face the opening heals better if it heals this way.  Without knowing the location and type of cancer treated, I would not jump to revision right away.

3 month is a very short time.  Indentation you see may be more noticable while there is still surrounding swelling and as it subsides, you may not need any additional surgery.

I would wait till 6 month after surgery and then discuss with your MOHS surgeon options for revision if needed and any contraindications based on the type of cancer removed.  There are some studies showing better survival of patients with advanced melanoma and decreased recurrence if the wound heals by secondary intention.

Sincerely, Boris Volshteyn MD