Association Between Undernutrition and the Number of Molar Occlusions in Older Persons Requiring Care in Long-Term Care Insurance Facilities

<b>Background/Objectives</b>: Undernutrition increases the mortality risk in older persons requiring long-term care; further, it is associated with oral functions such as swallowing and chewing. Moreover, occlusion affects oral function and is crucially involved in nutritional intake. The present study aimed to examine the association between the number of molar occlusions and undernutrition according to body mass index (BMI) in older persons requiring long-term care. <b>Methods</b>: Japanese older persons requiring long-term care were categorized based on BMI (<20 kg/m² vs. 20 kg/m²). We examined the association between undernutrition and the number of molar occlusions (one in each of the left and right premolars and molars, for a total of four). <b>Results</b>: Among 893 included participants, 440 (49.3%) had BMI < 20 kg/m² and 453 (50.7%) had BMI > 20 kg/m². Binomial logistic regression analysis revealed that BMI < 20 kg/m² was significantly associated with increased number of molar occlusions (odds ratio: 0.52-0.70, 95% CI: 0.28-1.00). This indicated that a decrease in the number of molar occlusions was associated with malnutrition as determined through BMI in older persons requiring long-term care and residing in long-term care insurance facilities in Japan. <b>Conclusions</b>: Our findings suggest that maintaining occlusal support may help maintain nutritional status in older persons requiring long-term care.