Purpose: The purpose of this study was to evaluate the occlusal force adjusting ability of implant-supported overdenture (IOD) wearers, as compared with natural teeth and complete dentures.
Methods: Subjects were those with natural dentition (ND group; 19 subjects), those with implant-supported overdentures (IOD group; 7 subjects), and those with complete dentures (CD group; 14 subjects). Subjects were asked to hold test foods (peanuts and biscuits mounted on a custom-made apparatus with a force transducer) between their anterior incisors (hold phase) and split test foods (split phase). The mean value of the occlusal force during the hold phase (hold force), the peak force rate during the split phase (peak force rate), the time required to split test foods (duration), and the maximum occlusal force in the split phase (split force) were selected as outcomes. Data were analyzed with Wilcoxon’s signed rank test, the Kruskal-Wallis test, and multiple regression analysis (Statistical significance levels: 5%).
Results: For peanuts, the peak force rate for the ND group was significantly higher than the IOD and CD groups. The duration of the CD group was significantly longer than the ND and IOD groups. Multiple regression analysis indicated that even with adjustment for age and sex, there were significant differences in the peak force rate between the ND and the IOD, CD groups, and in the duration between the ND and CD group.
Conclusions: Subjects with IODs showed superior ability to adjust occlusal force, as compared with complete dentures, although it didn’t match the natural dentition.