Factors related to masticatory performance in healthy elderly individuals

Purpose: Maintenance of natural dentition and/or prosthodontic rehabilitation is necessary for good masticatory function. Although other factors such as physical and oral functions are also important for masticatory performance, only a few studies have evaluated their roles. The aim of the current study was to assess factors associated with masticatory performance among elderly individuals, while maintaining and/or reconstructing all occlusal support areas. Methods: The present study was designed and implemented as a cross-sectional study, involving a total of 262 participants (mean age: 74.2 ± 5.9 years) who participated in the Kyoto Elders Physical Fitness Measurement Research Project. Individuals with partial or complete edentulousness who did not use dentures were excluded from the study. The predictor variables included physical status (i.e., age, gender, body-mass index, and grip strength), oral conditions (i.e., number of present teeth, temporomandibular joint noise, and denture wearer), and oral functions (i.e., maximum voluntary occlusal force; occlusal contact area; cheek pressure; oral diadochokinesis test /pa/, /ta/, /ka/; and maximum voluntary tongue pressure). The variable outcome was masticatory performance. These variables among the participants using univariate and multivariate analyses were compared. Results: Grip strength, number of present teeth, maximum voluntary occlusal force, occlusal contact area, oral diadochokinesis /ka/ /ta/, and maximum voluntary tongue pressure were significant factors for masticatory performance. Stepwise regression analysis showed that grip strength, maximum voluntary occlusal force, and diadochokinesis /ta/ significantly affected masticatory performance. Conclusions: Masticatory performance was closely associated with grip strength, maximum voluntary occlusal force, and diadochokinesis /ta/ among healthy elderly participants.