Question: Why is a dentist unhappy at work? Answer: Because he looks down in the mouth. The truth is that if you don't visit your dentist regularly, it could well be you who ends up looking down in the mouth.

A dentist does far more than just look after your teeth, says York dentist and former national president of the British Dental Association Stuart Robson.

He can spot early-warning signs about potentially more serious problems - such as mouth or throat cancer.

"One of the things that lots of people think is that dentists look after teeth and that's it," Mr Robson said.

"But we are just as much concerned with the overall health of the patient. One of the things we can do with regular checks is look at the soft tissues of the mouth - the gums, tongue and the inside of the cheeks - to see whether there are any serious problems. And one of those more serious problems we look for are any early-warning signs of oral cancers."

Today marks the beginning of oral cancer awareness week. It's a disease that is more common than you might think - and it's on the increase. The number of cases increased by a third between 1985-95. And, as usual, heavy smokers and drinkers are more at risk. The disease is also more common among older people - 94 per cent of those who develop it are aged over 45.

There are now 2,800 new cases a year - and 1,600 of those will prove fatal.

That figure could be a lot smaller, Mr Robson said, if only cancers were detected early enough. Of the 1,200 people whose cancers did not prove fatal, 95 per cent had been detected early.

"If they are detected early enough," Mr Robson said, "the success rate is very high indeed. On the other hand, oral cancers are one of the fastest-growing cancers anywhere in the body. If they aren't detected early the survival rate is less."

So the message is simple: if you don't want to end up looking down in the mouth, make sure you book a regular check-up. It just may save your life.

Stephen Lewis