Supawadee Naorungroj, DDS, PhD, from the University of North Carolina at Chapel Hill, and colleagues analyzed data from the Atherosclerosis Risk in Communities study for 11,097 participants from 1996–1998 to examine the correlation between oral health and cognitive function. Of the 9,874 participants who answered dental screening questions, there were 8,554 dentate participants, 5,492 of whom received oral examinations. Dental status, number of teeth, and periodontitis were assessed, and the associations with cognitive scores were estimated after adjustment for sociodemographic factors, cigarette smoking, alcohol use, and diabetes.
The researchers found that 27.3% of the dentate participants had <20 teeth and 12.4% had pocket depth of ≥4mm with severe bleeding. For all cognitive tests, edentulous participants had lower scores than dentate participants. Having fewer teeth and gingival bleeding (but not periodontal pocket depth) was associated with lower digit-symbol substitution and word fluency test scores among dentate participants.
“Our study findings add to the evidence that complete tooth loss, low number of teeth, and the inflammatory stage of periodontal disease are associated with lower cognitive,” the authors write.