To statistically evaluate the factors that influenced masticatory performance following Maxillectomy, masticatory performance was measured in 43 patients with a post-operative prosthesis by means of a spectrophotometer using adenosine triphosphate (ATP) granules. Our statistical analysis revealed that the number of occluding post-canine teeth and the patient's sex were factors that influenced masticatory performance and demonstrated that it was most important to improve occlusion in the pre-molar/molar region.