Purpose: To analyze the difference of masticatory muscle in bilateral distal-extension partially edentulous patients before and after prosthetic rehabilitation by surface electromyography.
Methods: Twenty-seven bilateral distal-extension partially edentulous patients were randomly selected, and be detected before and after prosthetic rehabilitation by surface electromyography. During the detection, the amplitudes of the anterior temporalis and masseter muscle were registered. Using them, the asymmetry index of total, asymmetry index of the masseter, asymmetry index of the anterior temporalis and mastication index were calculated. Student's t test was used to analyze the results.
Results: The asymmetry index of total and asymmetry index of the masseter in group of one month after prosthetic rehabilitation increased significantly than that in the group before prosthetic rehabilitation (P < 0.05); The asymmetry index of total and asymmetry index of the anterior temporalis in group of three or six months after prosthetic rehabilitation decreased significantly than that in the group before prosthetic rehabilitation (P < 0.05); The mastication index decreased gradually after prosthetic rehabilitation, the difference was also be significant between group of three or six months after prosthetic rehabilitation and group before prosthetic rehabilitation (P < 0.05).
Conclusions: After prosthetic rehabilitation, the equation and reservation of muscle's energy in bilateral distal-extension partially edentulous patients were significantly better than before. Whereas it costed more than three months for patients to adapt the dentures.