Patients with Myofascial TMD and with sleep bruxism with the diagnosis of regular or frequent teeth grinding sounds during the sleep, and one or more following clinical signs, such as jaw muscle pain or fatigue on waking up in the morning, temporal headache, hypertrophy of the masseter muscle, abnormal tooth wear, and/or jaw locking were included in the group.

Patients with Myofascial TMD without sleep bruxism were included in the group.

Patients with TMD regardless of diagnosis with sleep bruxism were assessed with the Jaw Function Limitations Scale (JFLS), Neck Disability Index (NDI), Pittsburgh Sleep Quality Index (PSQI), Fatigue Severity Scale (FSS), and Headache Impact Test-6 (HIT-6) scales.

The severity of pain in muscles was measured in centimeters using a 0-10 Visual Analogue Scales (VAS). The scale ranges from 0 = "no pain at all" to 10 = "intolerable pain"

The Jaw Functional Limitation Scale-20 was used to assess jaw function in the masticatory system. The scale consists of a total of 20 items with three constructs. Each item is scored from 0-10, with 0 indicating no restriction and 10, severe restriction. A total of ≥5 indicates jaw function limitation.

Neck problems were assessed with Neck Disability Index (NDI). It is a scale of 10 sections with total points ranging from 0-50. Higher scores indicate severe pain, and a score of ≥5 indicates a neck disorder.

The sleep quality was evaluated using the Pittsburgh Sleep Quality Index (PSQI). The scale comprises a total of 24 items in 7 sub-scales. The total points of the 19 items that score from 0-21, with a total of ≥5 indicating poor sleep quality.

The effect of fatigue on functional and behavioral aspects was evaluated by the Fatigue Severity Scale (FSS). The total score is calculated as the average of the 9 item scores -the lower the total score, the lower the fatigue level. A cut-off value of ≥4 has been defined for fatigue

The Headache Impact Test-6 (HİT-6) was used to assess the headache. The 6 items scale evaluating the frequency, the degree of restriction to daily life and social life, and changes in the mood because of headache. The total score 50-59 reflects important impact, and scores ≥60 indicate severe impact.