Pattern of Jaw and Neck Muscle Pain Among Different Abnormal Behaviors in a Group of Myofascial TMD Patients

Objectives: To investigate the pattern of pain intensity of jaw and neck muscles in TMD patients with history of abnormal jaw behaviors.
Methods: Thirty two TMD patients diagnosed as only myofascial pain (according to RDC/TMD criteria), retrieved from KKU Orofacial Pain Unit database during 2014-2015, were retrospectively reviewed for their abnormal jaw behaviors including bruxism, daytime clenching, unilateral chewing, snoring, and poor posture. The pain intensity (mild, moderate, severe) of clinically examined jaw and neck muscles was also recorded. The pain intensity of each muscle was compared between patients with and without such abnormal jaw behaviors.
Results: The results showed that patients with daytime clenching and snoring had significantly more pain in suboccipital muscles whereas patients with unilateral chewing habit had significantly more pain in masseter muscles (p<0.05, Mann Whitney U). Patients with bruxism and poor posture did not have more pain than those without.
Conclusions: It was suggested that different abnormal jaw behaviors might impose more injury on different groups of jaw and neck muscles in TMD patients.