My tb had terrible hooves when I first got him and he ended up abscessing badly. It was on and off lameness for about 6wks, then he started to abscess. We had several abscess in the space of a couple of months ( I know think the hoof was sealing up the exit point before the abscess had fully cleared. We then had a massive outpouring of pus ( I mean, from the sole of the hoof, several points on the front of the hoof wall, around the heel ). This lasted for 14 days, then stopped and hasn't had another abscess ( touching wood like mad ).
During this he was under vet and farrier care, and had been xrayed to check there wasn't other issues or infection going up the leg.
Kx