(By Dr. Joseph D. Lim and Dr. Kenneth Lester Lim, BS-MMG, DDM, MSc-OI)
EACH TOOTH matters.
And when you lose a lot of it, dentures are worth it.
The risk of cognitive decline grows with each tooth lost, a new analysis by researchers at New York University (NYU) shows.
However, the risk was not significant among older adults with dentures, the study found. It suggests that timely treatment with dentures may protect against cognitive decline.
The study, published in JAMDA: The Journal of Post-Acute and Long-Term Care Medicine, was conducted by researchers at NYU’s Rory Meyers College of Nursing.
The NYU Rory Meyers College of Nursing is highly ranked by U.S. News & World Report. It is among the top 10 nursing schools receiving funding from the U.S. National Institutes of Health (which partially funded the tooth loss and dementia study).
About one in six adults aged 65 or older have lost all of their teeth, according to the Centers for Disease Control and Prevention.
Previous studies show a connection between tooth loss and diminished cognitive function, with researchers offering a range of possible explanations for the link.
One possible explanation is that missing teeth can lead to difficulty in chewing. That, in turn, may lead to deficient nutrition and promote changes in the brain.
Gum disease is a leading cause of tooth loss; it has been linked as well to cognitive decline.
Socioeconomic issues may also lead to tooth loss and become risk factors for cognitive decline.
“Given the staggering number of people diagnosed with Alzheimer’s disease and dementia each year, and the opportunity to improve oral health across the lifespan, it’s important to gain a deeper understanding of the connection between poor oral health and cognitive decline,” said Dr. Bei Wu, PhD, Dean’s Professor in Global Health at NYU Rory Meyers College of Nursing.
Dr. Wu, the study’s senior author, is the co-director of the NYU Aging Incubator.
She and her colleagues analyzed 14 studies of tooth loss and cognitive impairment. The studies involved 34,074 adults and 4,689 cases of people with diminished cognitive function.
They found that adults with more tooth loss had a 1.48 times higher risk of developing cognitive impairment. They also had 1.28 times higher risk of being diagnosed with dementia.
Adults with missing teeth were more likely to have cognitive impairment if they did not have dentures (23.8 percent) compared to those with dentures (16.9 percent).
A further analysis showed that the association between tooth loss and cognitive impairment was not significant when participants had dentures.
The researchers conducted an analysis using a subset of eight studies to determine if a greater number of missing teeth was linked to a higher risk for cognitive decline.
They found that each additional missing tooth was associated with a 1.4 percent increased risk of cognitive impairment and 1.1 percent increased risk of being diagnosed with dementia.
“This relationship between the number of missing teeth and risk of diminished cognitive function substantially strengthens the evidence linking tooth loss to cognitive impairment, and provides some evidence that tooth loss may actually predict cognitive decline,” said Xiang Qi, a doctoral candidate from NYU Meyers.
“Our findings underscore the importance of maintaining good oral health and its role in helping to preserve cognitive function,” said Dr. Wu.
The study co-authors are Zheng Zhu of Fudan University in Shanghai and Brenda L. Plassman of Duke University in Durham, North Carolina.
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Dr. Joseph D. Lim is the former Associate Dean of the UE College of Dentistry, former Dean of the College of Dentistry, National University, past president and honorary fellow of the Asian Oral Implant Academy, and honorary fellow of the Japan College of Oral Implantologists and Honorary Life Member of Thai Association of Dental Implantology. For questions on dental health, e-mail jdlim2008@gmail.com or text 0917-8591515./PN
