Researchers found that tooth loss is linked to slower walking speed and poorer memory function in older people.
In the Journal of the American Geriatrics Society, the team from University College London (UCL) in the UK describes how they drew their conclusions after analyzing data from over 3,100 adults aged 60 and over living in England.
The data came from the English Longitudinal Study of Aging (ELSA) and allowed the researchers to compare performance in tests of memory and walking speed of participants who had none of their own teeth with equivalents who had some natural teeth.
The analysis showed that subjects who had lost all their natural teeth performed around 10% worse in both memory and walking than counterparts with natural teeth.
Lead author Dr. Georgios Tsakos, of UCL's Department of Epidemiology and Public Health, says the findings suggest:
"Tooth loss could be used as an early marker of mental and physical decline in older age, particularly among 60-74 year-olds."
The link between total tooth loss and poorer memory performance became insignificant when researchers took into account a wide range of factors, such as age, gender, smoking, drinking, depression, physical health, and - in particular - socioeconomic status (income, education and occupation).
However, the link between total tooth loss and slower walking speed remained significant when all these influencers were taken into account; people with none of their natural teeth still walked slightly more slowly than peers who had some of their teeth.
The researchers also looked at the link between losing all natural teeth and having poorer memory and slower walking speed 10 years later. This was noticeably stronger in the adults aged 60-74 years than in those aged 75 and over.
Regardless of the reason, tooth loss could be a marker for faster decline later in life
Dr. Tsakos says the causes of tooth loss and mental and physical decline are often tied to socioeconomic status, emphasizing "the importance of broader social determinants such as education and wealth to improve the oral and general health of the poorest members of society."
However, regardless of the underlying reasons for the link between tooth loss and decline in mental and physical function, noticing excessive tooth loss in adults is a chance to spot those at higher risk of faster decline later in life, he adds.
"There are many factors likely to influence this decline," he suggests, "such as lifestyle and psychosocial factors, which are amenable to change."
In August 2014, a paper published by the International and American Associations for Dental Research (IADR/AADR) in their Journal of Dental Research says while there has been a steep decline in tooth loss in the US in the last 50 years, the contrast between rich and poor is now stronger.
Total tooth loss is a rare condition in high-income households in the US nowadays; it has contracted geographically to states with disproportionately high poverty, note the authors.
Periodontal or gum disease is the most common cause of tooth loss among adults. A 2012 study by the Centers for Disease Control and Prevention (CDC) estimates that around half of the adult population in the US has periodontal disease, with cases ranging from mild to severe.
The prevalence is much higher in those living below the poverty line (over 65%), those with less than a high school education (nearly 67%), and among older Americans (around 70%), note the CDC. They add that among older Americans aged 65 and over, the prevalence rate is around 70%.