Reflection of ¹⁸F-FDG accumulation in the evaluation of the extent of periapical or periodontal inflammation

To elucidate whether fluorine-18-labeled ((18)F) fluoro-2-deoxy-d-glucose (FDG) accumulation can reflect the extent of periodontal inflammation, periapical inflammation, or dental caries.(18)F-FDG accumulations on positron emission tomography (PET)-computed tomography (CT) were retrospectively compared with the size of the bone resorption areas caused by periodontal inflammation, periapical inflammation, or dental caries on panoramic radiographs, CT, and magnetic resonance imaging (MRI) in 44 subjects.A significant correlation was found between the size of the bone resorption area caused by periodontal (r = 0.595, P.01) or periapical (r = 0.560, P.01) inflammation and the highest standardized uptake value (SUVmax) of (18)F-FDG accumulation. A significant correlation was found between the periodontal (r = 0.622, P.01) or periapical (r = 0.394, P.01) inflammatory findings on MRI and the SUVmax of (18)F-FDG accumulation. The SUVmax of (18)F-FDG around most teeth with caries was under 1.5.(18)F-FDG accumulation reflects the extent of dental inflammation, not dental caries.