London: In a finding that could soon render dentists out of business, scientists have discovered a new vaccine that can rid us of tooth decay for ever.
Researchers at the Forsyth Institute in the US are developing a vaccine that targets the bacterium `mutans streptococci`, which causes tooth decay.
When the bacteria break down food, they produce lactic acid, which wears away tooth enamel, producing cavities.
The new cavity-fighting vaccine teaches the immune system to make antibodies that kill the enzymes which enable bacteria to stick to teeth, the `Daily Mail` reported.
Unable to cling to tooth enamel, the bacteria are washed away by saliva, and the teeth are protected.
Rats given the vaccine in experiments developed almost no cavities. Trials on people have also found the vaccine to have a similar effect.
Ultimately the vaccine would be given to children under the age of one while their teeth are developing, but before the plaque bacteria have become established, researchers said.
"If given to children at a young age, we think it may prevent colonisation of plaque bacteria altogether," said Dr Daniel Smith of the Forsyth Institute.
"The bacteria wouldn`t be able to stick to teeth or gain a foothold. Children would be protected from caries for life," Smith said.
The vaccine protects teeth and reduces, rather than eradicates, bacteria in the mouth in adults. It will probably be administered as nasal drops, sparing children and adults the ordeal of painful injections.
"The nose and mouth are connected. If you give the vaccine nasally, you get antibodies in the saliva," said Smith.
Dr Jacinta Yeo, of the British Dental Association, believes the vaccine, which may be available in a few years, could revolutionise dental health.
"The research sounds exciting. If bacteria can`t stick to teeth, they can`t do harm," she says.
"Saliva can neutralise acids and kill bacteria, but it`s not effective enough to prevent damage by bacterial acids. It sounds as if this vaccine could equip the body with a natural defence system," said Yeo.