What is the best treatment for abnormal wound healing?

Many treatments: Relieving pressure is of paramount importance in most types of wounds . After that wound healing is directed to removal of dead tissue (slough, escar &callous) maintaining appropriate moisture(not to dry or to wet) and a good environment for growth of granulation through various treatments and good nutrition.

Avoid the bad: The real question is what not to do that slows down healing. Avoid using alcohol, peroxide, hibiclens, betadine, and bleach solutions. Inflammation ( red, hot, swollen, tender) is important to healing so anti-inflammatories (motrin, advil) are bad. Cover the area with a clean dressing changed every other day and protected from trauma. Antibiotics do not help healing unless it is truly infected.

See a specialist: If you have a bad wound that isn't healing then you need to see a wound care specialist. They are trained to look at everything to see what is wrong and then treat the wound.