Electromyographic evaluation of perioral muscle activities during facial expression and button-pull exercise.

BACKGROUND: Muscle weakness negatively affects perioral muscles and quality of life. The button-pull exercise is used to teach lip closure (LC) and to strengthen muscles. However, how the muscles accomplish LC during button-pull and its training effect on each muscle are unknown. OBJECTIVES: This study aimed to investigate the LC mechanism and the efficacy of perioral muscle training. METHODS: Electromyographic (EMG) activities were obtained from perioral muscles along with the lip closing force (LCF) and were normalised to the maximum LC activities. Correlations between muscle activities and LCF were assessed during LCF increment/decrement task. The effectiveness of training methods was evaluated during functional face tasks (FFT). The effects of button-pull on muscles were evaluated during static loadings with two sized buttons. RESULTS: The muscles were active during LC, and the amplitudes changed with the LCF. In FFT, the muscles were simultaneously active and the total activity was highest during the blowing task. In button-pull, maximum button-pulling forces (BPFs) were significantly larger with the large button (p = .0001). In the static loading task, muscle activities increased with increasing button load. However, the small button produced significantly greater EMG activity than the large button in most of the load (p < .005). CONCLUSION: LC is accomplished by the cooperation of perioral muscles. In button-pull, a larger button requires a larger BPF, but a smaller button shows higher muscle activities. Face expression exercises compare favourably with button-pull. Forceful LC and blowing tasks may be effective and balanced training of the perioral muscles.

UV dose measurements of photosensitive dermatosis patients by polycrystalline GaN-based portable self-data-acquisition UV monitors.

We have developed a UV monitor with polycrystalline (poly-) gallium nitride (GaN) UV sensors and evaluated its performance from the viewpoint of its effectiveness for use with photosensitive dermatosis patients. The poly-GaN UV sensor is sensitive to UV light from 280 to 410 nm even without optical filters. The UV monitor is a portable self-data-acquisition instrument with a minimum detection level (defined as average UV intensity over 290 to 400 nm) of 2 microW/cm2 and can store UV dose data for 128 days. It allows easy measurement of four orders of magnitude of ambient UV intensity and dose from indoor light to direct solar radiation in summer. Trial use of the UV monitor by five xeroderma pigmentosum patients started in June 2000 and was carried out for 1 year. It was demonstrated that the UV monitor was useful in improving their quality of life.