2016 Volume 31 Issue 3 Pages 337-345
Introduction：In patients with velopharyngeal incompetence（VPI）, blowing training is frequently applied. Because the blowing method, in which patients blow through a straw whose other end is in water in a cup, can improve oral lip closure function, it is widely used to improve the oral function of aged patients. Therefore, in this study, we investigated the influence of such conditions for soft-blowing on the level of muscle activity of the orbicularis oris and submental muscles, and evaluated the load during soft-blowing.
Materials & Methods：The subjects were 10 healthy adults（mean age 27.6 years）without objective or subjective abnormalities of the stomatognathic system. The posture during measurement was sitting at 90 degrees, the subjects held a container in which a straw was inserted into the test specimen, and blew through the straw to cause bubbling of the specimen for as long as possible. The width was set at 6, 10, and 15 mm, and evaluation was performed using three types of straw, combining these conditions. Furthermore, the viscosity of the test specimens was set at 0, 2, 4, and 6% by dissolving a thickener（Tsururinko Quickly, Clinico Co., Tokyo）in 100 ml of water. Muscle activity was recorded in the area of the orbicularis oris and submental muscles. Under these conditions, the level of activity of each muscle was evaluated.
Results：A positive correlation between the level of activity of the orbicularis oris and submental muscles and the viscosity of the test specimens was observed.
Conclusion：These results suggest that it is effective to adjust the load based on the viscosity of water during blowing training.
