Association Between Mastication Pattern, Periodontal Condition, and Cognitive Condition—Investigation Using Large Database of Japanese Universal Healthcare System

Abstract

The decline in oral health commonly occurs as a natural consequence of aging or due to various pathological factors. Tooth loss, which diminishes masticatory ability, has been associated with negative impacts on cognitive function. This observational study analyzed dental and medical records from Japan’s Universal Healthcare System (UHCS) national database to investigate the relationship between cognitive and oral disorders, focusing on periodontitis and decreased tooth-to-tooth contact between the maxillary and mandibular arches. A descriptive data analysis evaluated diagnostic codes for Alzheimer’s disease and cognitive impairment alongside dental treatment records from 2013 to 2018. The odds ratios for cognitive impairment in patients with partial loss of natural tooth contact were 1.6663 (p < 0.05) for early elderly individuals (aged 65–75) and 1.5003 (p < 0.0001) for advanced elderly individuals (over 75). Periodontally compromised patients had higher odds, with ratios of 1.3936 (p < 0.0001) for early elderly individuals and 1.1888 (p < 0.00001) for advanced elderly individuals, compared to their periodontally healthy counterparts. These findings suggest a potential link between cognitive health, natural tooth contact preservation, and periodontitis, with the loss of natural tooth contacts having the most significant impact on cognitive function.