RÉSUMÉ
In order to measure and analyze three dimensional masticatory muscle force vectors in craniofacial region, the multiresolution method based on wavelet pyramid was used for the fusion of cranio jaw facial CT and MRI image, then these images were visualized. The results showed that the area of physiological cross section (PCS) and the maximum muscle force were different during functioning in the masticatory muscles system. The various masticatory muscle forces or various sides in the same muscle were also different in the three dimensional directions. The results suggested that determination of three dimensional masticatory muscle vectors is feasible by CT and MRI fusion image technology in craniofacial region, and can provide significant results for the basic research in the masticatory muscle system.