Development and experimental evaluation of oral rehabilitation robot that provides maxillofacial massage to patients with oral disorders

We have developed an oral-rehabilitation robot WAO-1 (Waseda Asahi Oral-rehabilitation robot No. 1) for use in cases of oral disorders such as temperomandibular joint (TMJ) disorder and dry mouth. WAO-1 is the first robot designed to provide massage to the facial tissues of a patient with oral disorders. This robot provides massage to the masseter and temporal muscles and to the parotid gland and duct with simple operation. It consists of two six-degree-of-freedom arms with plungers, a body with headrest, a control box, a PC, and an automatic massage trajectory generation system with virtual compliance control. Two evaluation experiments were performed to verify the effectiveness of the oral massages of WAO-1 compared with the massages given by doctors. In the experiments, the massage to the parotid gland and duct by WAO-1 increased the amount of saliva in the subjects, and the massage to the masseter muscle by WAO-1 increased facial skin temperature and width of the masseter muscle in the subjects. We consider that these results indicate that massage by WAO-1 can be effective for patients with oral disorders.