Assessment of subjective and objective masticatory function among elderly individuals with mild cognitive impairment

Abstract

Background Masticatory function is known to be related to cognitive ability; therefore, factors for improving masticatory function should be identified. Aims This study aimed to identify factors influencing masticatory function associated with mild cognitive impairment (MCI) in elderly individuals. Methods A total of 123 elderly participants [mean age: 76.5 ± 6.5 years; 82 females (66.7%), 41 males (33.3%)] were included. Cognitive function was evaluated by the Korean version of the Mini-Mental State Examination (KMMSE). Questionnaires for subjective evaluation were administered, and dynamic objective masticatory function evaluations, including chewing tests and bite force measurements, were performed. Intergroup differences were evaluated by the Wilcoxon rank-sum and chi-square test, and correlations between cognitive ability and masticatory function were evaluated by multilinear logistic regression. Results The number of teeth, number of posterior teeth, bite force, masticatory ability index (MAI) and posterior support status showed significant differences between the normal (KMMSE > 23) and MCI (KMMSE ≤ 23) groups. However, only the MAI, representing dynamic masticatory performance, was significantly associated with MCI regardless of age, sex and removable prostheses. The number of teeth and posterior teeth, bite force, subjective masticatory ability and posterior occlusal support showed no significant association with MCI. Discussion These results suggested the importance of chewing function for preventing the progression of cognitive impairment. Conclusions Considering that only the MAI was significantly associated with MCI, it is more important to improve chewing efficiency by harmonizing therapeutic prosthetics with the surrounding masticatory system than simply increasing the number of teeth to prevent or delay cognitive impairment in elderly individuals.

Factors associated with age-related changes in oral diadochokinesis and masticatory function in healthy old adults

“…The participants were healthy enough from the perspective of physical and mental conditions to manage ADLs and instrumental ADLs [ 26 ]. In addition, they had at least 20 teeth, which is considered a sufficient number of teeth to support masticatory function based on the short arch concept [ 4 , 21 , 26 ].…”

“…Lee et al reported significant associations between MP and the KMMSE score in older individuals [ 21 ]; therefore, a significant multilateral association could be expected among the KMMSE score, MP and ODK. In reality, in Gr3, both the KMMSE score and ODK /ka/ emerged as significant factors associated with MP, and ODK /pa/ showed a more significant association than in Gr2, where ODK /pa/ta/ was distinctively associated with MP (Table 6 ).…”

“…For masticatory function evaluation, both subjective and objective assessments of various orofacial factors were performed. Methodologies for subjective and objective masticatory assessment identical to those used in our previous studies were applied [ 21 , 22 ]. Two trained researchers conducted both objective and subjective masticatory examinations for all participants.…”

“…Participants were asked to press the balloon probe against the anterior hard palate, maintaining peak pressure for approximately 7 s, and the average of three trials was recorded. BF and OA were assessed utilizing a bite force analyzer (Dental Prescale 50 H, GC, Tokyo, Japan) [ 21 ]. HG, reflecting overall bodily strength, was tested using a handheld dynamometer (TKK 5401, Takei Scientific Instruments Co., Ltd., Tokyo, Japan) [ 22 ].…”

Digital oral health biomarkers for early detection of cognitive decline

“…Oral frailty has been associated with an increased risk of new-onset MCI [ 4 ]. Previous studies have revealed that the number of teeth present, occlusal contact area, and maximum bite force are significantly higher in cognitively normal subjects than in impaired subjects [ 5 , 6 ]. Lee et al pointed out that masticatory function measured by the objective mixing ability test was significantly associated with MCI [ 6 ].…”