Correlation analysis between elderly oral myofunction, oral microorganisms, and cognitive function

Objectives: This study aimed to analyze the correlation between oral function, oral environment, and brain cognitive function in the elderly. Methods: The subjects were 60 users of senior community center and elderly day care center. The survey was conducted from November to December 2018. Subjects were assessed by oral examination and myofunction test. Oral myofunction was measured using $IOPI^R$ and Lip de $Cum^R$. Survey data were analyzed using the statistical programs of PASW Statistics ver. 18.0. Results: Tongue muscle strength and lips muscle strength was higher in males than in females. The tongue and lip strengths were higher in the <81 years old group than the ${\geq}81$ years old group. Functional tooth analysis showed that there was a ${\geq}15$ teeth group ($40.91{\pm}7.36$) and a <15 teeth group ($32.52{\pm}7.14$). Lip muscle strength analysis showed that the ${\geq}15$ teeth group ($10.54{\pm}3.40$) was higher than the <15 teeth group ($8.20{\pm}2.41$, p<0.05). Tongue muscle strength, lumbar muscle strength, and functional tooth number were lower in the elderly subjects with mild cognitive impairment. Cognitive function was significantly correlated with functional tooth number (r=0.386, p<0.001), tongue strength (r=0.478, p<0.001), and lip strength (r=0.281, p<0.05). Tongue strength was significantly correlated with lip strength (r=0.360, p<0.001) and functional tooth number (r=0.633, p<0.001). Lip strength was significantly correlated with functional tooth number (r=0.376, p<0.001). Conclusions: These results showed that age and functional tooth number influenced oral muscle strength and that the number of functional teeth and oral muscle strength were low in the elderly with mild cognitive impairment. Oral myofunction training and oral care program are suggested to improve the quality of life of the elderly.