A Three-Item Oral Function Impairment Score Is Associated with White Matter, but Not Gray Matter, Volume Ratio in Older Adults: A Cross-Sectional Study

Background/Objectives: Declining oral function is associated with adverse health outcomes in older adults; however, its relationship with underlying brain structure remains unclear. We examined whether a three-item oral function impairment score (OFIS), based on the number of present teeth, tongue pressure, and oral diadochokinesis (ODK), was associated with white matter (WM) and gray matter (GM) volume ratios in community-dwelling older adults.