Gum disease has been linked to a greater rate of cognitive decline in people with Alzheimer's disease, early stage research has suggested.
The small study, published in , looked at 59 people who were all deemed to have mild to moderate dementia.
It is thought the body's response to gum inflammation may be hastening the brain's decline.
The Alzheimer's Society said if the link was proven to be true, then good oral health may help slow dementia.
The body's response to inflammatory conditions was cited as a possible reason for the quicker decline.
Inflammation causes immune cells to swell and has long been associated with Alzheimer's. Researchers believe their findings add weight to evidence that inflammation in the brain is what drives the disease.
The study, jointly led by the University of Southampton and King's College London, cognitively assessed the participants, and took blood samples to measure inflammatory markers in their blood.
Their oral health was also assessed by a dental hygienist who was unaware of the cognitive outcomes.
Of the sample group, 22 were found to have considerable gum disease while for the remaining 37 patients the disease was much less apparent. The average age of the group with gum disease was 75, and in the other group it was 79.
A majority of participants - 52 - were followed up at six months, and all assessments were repeated.
The presence of gum disease - or periodontitis as it is known - was associated with a six-fold increase in the rate of cognitive decline, the study suggested.
View study here: Periodontitis and Cognitive Decline in Alzheimer’s Disease