The root causes of jaw tightness and discomfort can often be traced back to one of three main sources.
Temporomandibular Joint Disorders or TMJ. These disorders can be caused by an incorrect bite, misaligned teeth or dental trauma and result in jaw tightness or even difficulty opening the mouth. TMJ can usually be treated by a dentist but this will depend on the exact cause of the problem.
Bruxism. Also called teeth grinding, bruxism usually occurs during sleep and puts excessive stress and strain on the teeth and jawbone. Bruxism can also cause enamel erosion and chipped or fractured teeth.
Stress. Stress and anxiety often manifest through tension of not just the body but also the neck and head. This includes tightening of the jaw which can result in jaw pains as well as headaches and migraine.
The good news is that effective treatment is available for bruxism, stress and TMJ disorders -- and the sooner the problem is addressed the quicker and easier it will be to treat. More detailed information can be found at https://yourdentalhealthresource.com/jaw-tightness-and-tension-what-does-it-mean/.