Hello, I am a 62-year-old female in good-to-excellent health. I m under some stess right now, due to leaving a position I ve had for 20 years to accept a big promotion and substantial salary increase, but in another city; my partner will be staying in our home and maintaining it, while I move seven hours away. He will visit me and vice versa, but packing and the transition is much on my mind. Upon awakening from a normal night of sleep today, after several minutes of conversation, my jaw locked open and wouldn t move. I gingerly moved it around manually, and got it to close with a loud and resounding POP from the right side of my face, which seems to have been the problem side. No pain, to my surprise, but it almost immediately opened and locked again, on the right side joint where the lower jaw aligns with the cheek. I was able to successfully move it around and again, it seemed to resolve with a resounding pop. Quite unnerving. My lower jaw seemed to want to move back and forth laterally, throughout the day and while I ve inspected my face in a mirror and don t see any unusual misalignment, it feels as if my jaw wants to settle farther to the right than usual. I don t notice any difference in my bite, and my teeth feel normal. If I bite down, I feel a very minor soreness in the right cheekbone area, above the rear molar, which was pretty close to the site of the lock-up. This has never happened to me before. I m in good overall condition and health, have all my teeth, and am generally youthful. Can you make an informed guess about what might have happened, and whether I should follow up with my PCP, or do anything to keep this form happening again? Many thanks for whatever speculation you may want to offer.