Any periodontist here? Need opinion.

How is apical periodontitis treated? What to do for periodontal ligament widening?have constant jaw pain under ear and neck for 15 months now. Have tapping and biting pressure on tooth 46.had root canal and crown. Still no changes. Same pain for Biting pressure on it. It hurts in tooth and gum even if pressed with fingers.have neck pain and have small lump for more than an year. CT scan normal.  I have jaw clicking and grating sound. Taken MRI,CT of jaw. Normal.They said it's Myofascial pain and doing physical therapy for it.  Biting on this tooth on qtip hurts in the lower jaw under ear lobe. I am not chewing on it or using that side at all for eating. Using only the opposite side.   I went for another Endodontist opinion. He took x-rays and said tooth 46 has apical periodontitis. Not sure if it's been present since beginning of this pain episode. He put me on antibiotics to see if it helps.  Tooth 47 has periodontal ligament widening. does apical periodontitis cause so much pain?