I had two small warts on the bottom of my foot frozen off a year ago at my dermatologist. theyre quite small. just a cluster of two. i go to look the other day after a full year and the warts are still there, however theyre white. why is this? ty?

These warts are difficult to eliminate. Their substance extends deep below the skin surface like an iceberg. Treatment tries to kill it all at one setting but if any infected cells remain deep inside it can gradually grow out again. Retreatment of plantar warts is common. If the initial treatment is too deep, you can kill normal tissue & create a deep hole that takes forever to heal.