Well, my tb gelding popped 3 last winter, (first winter with him) and my tb mare who I had for 3 years before she passed away, never had an abscess ever, and they lived on the same ground, did the same work, same farrier etc.
I have been told my boy has very good hooves for a tb, but from what I have gathered during his 3 consecutive abscesses, the first was after a stone bruise after his hooves were trimmed a little too enthusiastically (not my farrier!!) the second was in the other front hoof, and we think it may have been the wet conditions he was in making his hooves soft, and of course, with soft hooves comes easier penetrations from foreign objects, which then causes an infection at the site of penetration (which usually closes up after penetration, leaving the foreign object in there). That, in turn, means that the antibodies are going "nooo get it out of here", and the infection is the bodies way of trying to get rid of the object(eg stone/stick etc).
They take the path of least resistance, which seems to be the coronet band, so in my experience, an abscess left untreated will eventually burst through the coronet band. Though sometimes they can burst through the sole.
The next problem was that because his hooves had been wrapped and poulticed, when it came to leaving them unwrapped, his hooves were soft still, from poultice etc, so he developed yet another abscess.
With this horse, it significantly improved his hoof health to have him standing in a dry concreted yard for some of the day, or walking him up the road, to give his hooves a chance to dry out and be harder again. He didn't develop another one after we did that. (so far! Winters just arrived again)
-However, I am no professional and definately don't claim to be!! Remember that