Journal of oral rehabilitation
-
Randomized Controlled Trial
Effect of conditioning electrical stimuli on temporalis electromyographic activity during sleep.
Inhibitory reflexes during voluntary contractions are well described; however, few studies have attempted to use such reflex-mechanisms to modulate electromyographic (EMG) activity in jaw-closing muscles during sleep. The aim was to apply a new intelligent biofeedback device (Grindcare(R)) using electrical pulses to inhibit EMG activity in the temporalis muscle during sleep. Fourteen volunteers participated who were aware of jaw-clenching activity as indicated by complaints from sleep partner, soreness or pain in the jaw-muscle upon awakening and tooth wear facets. ⋯ There were no session effects on the average duration of sleep hours (P = 0.626). The number of EMG episodes/hour sleep was significantly reduced during the two sessions with biofeedback (54 +/- 14%; 55 +/- 17%, P < 0.001) compared with baseline EMG activity and the session without biofeedback. The present study suggests that biofeedback with electrical pulses does not cause major disruption in sleep and is associated with pronounced reduction in temporalis EMG activity during sleep.
-
The study aimed to assess the distribution of temporomandibular disorders (TMD) sub-types, psychological distress and psychosocial dysfunction in southern Chinese people seeking treatment for TMD using Research Diagnostic Criteria for TMD (RDC/TMD) and investigate potential cross-cultural differences in sub-type prevalence and psychosocial impact. Eighty-seven consecutive patients (77 females; 10 males) with a mean age of 39.3 years (s.d. 12.8) newly referred to the specialist TMD clinic at the Prince Philip Dental Hospital, Hong Kong over a 20-month period took part in the study. RDC/TMD history questionnaire and clinical assessment data were used to derive Axis I and II findings. ⋯ While acknowledging the small sample size, the distribution of RDC/TMD Axis I and II diagnoses was fairly similar in Chinese TMD patients compared with Western and other Asian patient groups. However, in Chinese patients, myofascial pain with limited jaw opening and TMJ disc displacement with reduction were more common and a significant number experienced psychological distress and psychosocial dysfunction. The findings have implications for the management of TMD in Chinese people.