The aim of this study was to compare quantitatively the masticatory performance of patients with overdentures supported by two implants, conventional complete dentures, and natural dentitions. Each patient was asked to chew a gelatin cube. The collected remains of the test food (gelatine cube) were fractioned by a sieving procedure and weighed. Maximum mouth opening and masticatory area were measured using kinesiography. There were statistically significant differences among groups with respect to masticatory performance using a 3.15-mm-diameter sieve (P .001) and 0.5-mm-diameter sieve (P .001), masticatory area (P = .019), and maximum mouth opening (P .001). Increasing retention of a mandibular complete denture with two implants improved masticatory performance.