I may need to do a root surgery cos root canal has failed and there is a metal post in the tooth, which I understand make it hard to redo a root canal retreatment.. so root surgery seem to be only choice? or should i go straight to implant? I think it's called apicoectomy. would doing the root surgery damage the bone structure make it hard if I need dental implant down the line? or does the bone grow back after the surgery? Also what's the success/risk of a apicoectomy or 'reverse root canal'?