Do you hear a popping sound when you open and close your mouth? Do you feel tenderness and discomfort in your jaw after opening your mouth wide, for example after eating a big meal. You might be suffering from the effects of TMD, or temporomandibular disorder. TMD is an issue that can arise from problems with the jaw joints and face muscles. When the temporomandibular joint, which is the hinge that attaches your jaw to your skull, becomes misaligned, it can lead to discomfort and leave lasting effects.