A novel sensor for bite force determinations

Abstract

Objectives. The clinical usefulness, accuracy and precision of a novel bite force sensor based on force sensing resistors were tested in six subjects wearing maxillary removable partial dentures retained by conical crowns. Methods. The surfaces of the sensor were manufactured in a silicone material that had mechanical properties similar to those of tough foodstuffs. In two separate series of standardized bite force tests, submaximum force levels were recorded with the sensor and with a strain gaged bite fork. Subjects were assisted in the loading tests with visual feedback instrumentation. Reliability estimates for the bite force sensor were calculated in order to show their reproducibility. Strain gages attached to the prostheses were used to determine the pattern of force distribution during loading tests. The bite force results obtained with the new bite force sensor and with the bite fork were analyzed with ANOVA and Scheffés tests. The strain patterns registered with strain gages were analyzed with F-test. Results. The bite force sensor and the bite fork transducer showed no statistically significant differences in respect of intra-individual bite force levels (range 50–300 N). The bite forces registered with the new sensor were dependent on the loading position ( p<0.05), sex ( p<0.05) and test subject ( p<0.05). The reliability of the new sensor for submaximum bite forces was calculated to be 93%. Strain gage results showed that the new sensor generated strain patterns of less variance ( p<0.05) than the bite fork and therefore allowed for higher precision during biting tests. Significance. The presented instrument has such clinical merits, as to favor its use in experimental clinical studies on the biomechanics of prosthetic appliances.