What do I use to heal an open wound from plantar wart? Corn cushion does not work. Been using it for months. It reopens with pressure.

Plantar wart. i would suggest seeing a podiatrist to be evaluated for the best treatment.
See physician. Best to see your primary care physician, a podiatrist, or a dermatologist for help. You may need cryotherapy (liquid nitrogen freezing) to treat the open plantar wart. The blistering of the superficial skin layers kill the virus along with the skin.