Comparison of muscle activity between conventional and neuromuscular splints.

The muscle relaxation appliance (MRA) has been used in the treatment of myofascial pain dysfunction (MPD) patients. The neuromuscular orthotic is a version of the MRA and is constructed from a three-dimensional mandibular position when muscles are in a state of minimal electromyographic (EMG) activity. The purpose of this study was to investigate the affect of two muscle relaxation appliances and a placebo (cotton rolls) on EMG activity of the functional masseter and anterior temporalis muscles. A centric relation mandibular MRA and a neuromuscular orthotic were constructed under controlled protocols for 12 women MPD patients with a mean age of 38 years. EMG measurements were taken during a 10-second clench of both appliance and placebo. No statistical difference was found between the centric relation mandibular MRA and neuromuscular orthotic. A statistically significant difference was found between the mean EMG values of the placebo and two treatment appliances.