Jaw popping and locking, can't open all the way. is this serious?

TMJoint issues: Relatively. As time goes on it may become even worse. See a dentist, preferably one who has extensive training and experience treating TMJ/TMD dysfunction. Why not be comfortable and free of these issues?

TMJ: TMJ problem. Relatively advanced. See TMJ expert. Any dentist can be a TMJ expert with the proper training and experience. Most commonly, oral surgeons, prosthodontists, and orofacial pain specialists. Ask your MD, your dentist and your dental society for referrals.