What causes a tooth to hurt when biting down on hard/crunchy food with a new crown thats adjusted to fit my bite? the tooth had a root canal 4 years ago and was recently shaved down for a new crown (the old crown broke). it had an apicoectomy in feb?

Great Questions! Teeth hurt on biting when there is infection around the root or at the apex, or if the tooth is fractured or if the "bite" is high. Root canal treated teeth quite often fracture with time because the blood supply keeping the nerve healthy and the tooth supple and elastic are no longer there. Go back to your dentist immediately.

This tooth has seen a lot of TLC... root canal therapy 4 years ago, and a recent surgery to further try to treat a problematic tooth. If your bite is good, then the tooth is fractured, there is inflammation at the apex, or an accessory canal that is untreated. Unfortunately some teeth do not respond favorably to the best care. Healing time after surgical tx can take six months.