How is your horse doing? Dexter had an abscess blow out of his foundered foot and it took enough sole that his coffin bone was visible. A mixture my vet made with formaldehyde that we put on daily covered with gauze and a tape boot for seven days closed the hoof. Kept him on stall rest in deep sawdust until it closed up. Once it’s healed get your farrier to glue on a shoe with equipak copper. It will stimulate the sole to grow thicker and keep thrush out.