Tooth or gums hurt on pressure from one side, no other pain.dentist says x-rays are fine, tapping tooth cause no pain.what could be the cause of pain?

Reason: There is a reason. When dentists can'f find a reason for a painful tooth, referral to an oral surgeon or endodontist is sometimes useful.

Re-examination: Radiographs are but one tool that dentists use to help determine what might be amiss with your teeth. A physical examination, periodontal probing, and checking of vitality are other means. Radiographs don't always show everything. If your dentist is stumped, a referral to an endodontist or periodontist is in order.