A jolt of electricity could help relieve a dry mouth BLAME THE ANCESTORS
ThiS week: A prominent chin. CHINS are unique to humans, and why we have them is hotly debated among scientists.
For years, the consensus was we evolved chins to protect our jaw and mouth — some have suggested they c a me about because of our unique speech patterns, protecting tongue muscles as we open our mouths.
Others argue that men and women’s chins have evolved differently to cater for what the other sex finds appealing.
University of Iowa researchers say they have found the answer. ‘Our study suggests that chin prominence is unrelated to function and probably has more to do with spatial dynamics during development,’ says Nathan Holton, professor of orthodontics.
‘That is to say that chewing and speaking has little to do with the origin of our chins.
‘Our faces have been getting smaller since the time of the Neanderthals. In fact, our faces are 15 per cent smaller than they were 200,000 years ago. That difference has made our chin more prominent on our faces.’
AJoLT of electricity may be a new way to tackle dry mouth. The electricity is delivered via a flat pad, 2½ cm (1 in) square, which is placed on the jaw — this stimulates the saliva glands beneath the skin and boosts the amount of fluid produced.
Results from a recent trial showed the device increased saliva production by an average of 13 per cent.
Dry mouth and lack of sufficient saliva are a common problem that affects one in ten adults at some time.
Saliva, which plays an important role in oral health, is produced by three major pairs of salivary glands and up to 500 minor glands. They produce about 1.5 litres (2½ pints) of saliva a day.
Dry mouth can affect dental health — enzymes in saliva help to break down food, while a number of other compounds fight the bacteria that form plaque and cause decay and gum disease.
As well as tooth decay, dry mouth has been linked to mouth ulcers, bad breath, ‘ burning’ mouth (a hot sensation in the mouth, tongue and lips) and an altered sense of taste.
It can also affect digestion and quality of life. Dry mouth becomes more common with age, typically because it’ s a symptom of conditions such as diabetes.
It is also a side- effect of drugs used to treat a range of problems i ncluding cancer, depression, anxiety, asthma, colds, acne, epilepsy and high blood pressure.
Treatment includes sucking on i ce chips or special gels and ‘substitutes’ — solutions with i ngredients that i mitate the protective compounds in saliva.
The new treatment involves mild el ectrical st i mulation delivered via a generator through an electrode pad placed on the skin over the saliva-producing glands. The treatment is painless, causing just a mild sensation under the pad.
In the new trial, 80 men and women aged 20 to 50 with dry mouth sat upright while saliva was collected from their mouths for five minutes.
After two minutes, the electrical st i mulation was gr a duall y increased and saliva collected over a second five-minute period. Results in the Journal of Clinical and Ex p e r i me nt a l Dentistry, show 65 people had an increase in their
flow of saliva following stimulation. The theory is that the electric impulses act on nerves involved in the function of the salivary glands.
‘The greatest advantage of this technique over others i s the almost complete absence of any l asting side- effects,’ say the researchers from Pacific University and other centres in India and the U.S.
‘It may be useful in the management of salivary gland low-level functioning when other therapies have failed or are not suitable.’ CoMMEnTIng More trials are planned.
on the findings, Professor David Bartlett, of King’s College London Dental Institute, said: ‘It is an interesting concept, but this is a small study and more work is needed.
‘We also need to know how long the stimulation would need to be applied and how practical it is.’
MEAnWHILE, electrical stimulation of the ear may offer a new means of tackling motion sickness.
A tiny current is passed into the outer ear using a hand-held device to stimulate the nearby vagus nerve, which is thought to play a role in nausea.
The vagus nerve stretches from the skull to the pelvis and plays a role in a number of key body functions.
Vagal nerve stimulation has been used to treat pain and epilepsy.
To test the treatment for motion sickness, researchers at the Wingate Institute of neurogastroenterology, London, have produced a ten-minute video that induces motion sickness in around half of people.
The researchers will then use the device to treat symptoms in 25 motion sickness sufferers.