Chief Executive of the British Dental Health Foundation, Dr Nigel Carter, has expressed major concerns following the latest study to show a relationship between tooth loss and dementia.

The new study tested more than 4,200 individuals and found that those who had fewer of their own teeth were at increased risk of experiencing memory loss or early-stage Alzheimer's disease.

The Japanese participants, who were all 65 or older, were given a full dental examination and a psychological assessment.

Dr Carter said this most recent study adds to the growing evidence that poor oral health and memory decline are related.

Dr Carter said: "This study only goes to strengthen the possible link between tooth loss and memory. Previous studies have suggested there might be a link between a low number of teeth and Alzheimer's disease and baseline dementia and the case towards a possible link seems to be growing ever stronger."

"We already know that good oral health has a positive impact on overall health, and likewise, the evidence towards poor oral health and systemic links is mounting.

"Heart disease, strokes, diabetes, lung disease and pre and low weight babies have all been found to be linked with poor oral health. This latest research highlights yet another worrying risk factor of having poor oral health."

The study also revealed that participants with symptoms of memory loss tended to report that they had rarely visited the dentist, if at all.

Dr Nozomi Okamoto, the study's principal investigator, said that this may be one explanation for the study's findings but suggested that there may be other links between tooth loss and memory problems.

Dr Okamoto said: 'Infections in the gums that can lead to tooth loss may release inflammatory substances, which in turn will enhance the brain inflammation that cause neuronal death and hasten memory loss.

'The loss of sensory receptors around the teeth is linked to some of the dying neurons.'

Gum disease is the major cause of tooth loss in adults but Dr Carter said that many people are still unaware of the relationship.

Dr Carter added: "In people who have gum disease, it is thought that bacteria from the mouth can get into the blood stream. It could then affect the heart by sticking to fatty deposits in the blood vessels of the heart. This can mean clots are more likely to form. Blood clots can reduce normal blood flow, so that the heart does not get all the nutrients and oxygen it needs. If the blood flow is badly affected this could lead to a heart attack.

"Some studies have shown that people with gum disease are almost twice as likely to have coronary artery disease as those without gum disease.

"It has long been known that diabetics are more likely to suffer from gum disease. This is probably because diabetics are more likely to get infections and generally heal at a slower rate.

"While we can never reverse the effects of existing gum disease as long as you take good care of your oral health you can prevent any further damage.

"To keep your gums healthy make sure you remove plaque every day by brushing for two minutes night and morning and cleaning in between teeth with interdental sticks or floss, and go for regular check-ups with the dentist and hygienist, as often as they recommend."

The findings of Dr Okamoto's study were published online in December's Behavioral and Brain Functions.