What works?

No. 9 What kind of fillings are best?

The problem: New types of fillings are used by dentists with little research into which last longest or havethe greatest benefits. The better- researched amalgam,or mercury, fillings have been in use for more than 100 years, but recently concerns have been raised about their safety with some alleging that vapours from the mercury cause mental impairment.

Is a filling for life? No. About 60 per cent of fillings are replacements and the same tooth may have to be refilled several times. There are many reasons for this. The simplest is that fillings wear out and decay recurs. But there is also huge variation in dentists' practice. High street dentists replace fillings far more often than those in dental schools. Changing dentists can double your chances of having a filling replaced - because a dentist is often more cautious treating a new patient. The dentist's skill can be a factor, but it is also thought that the way dentists are paid - per treatment - encourages unnecessary fillings. In addition, different types of fillings last significantly longer than other.

So which fillings are best? Amalgam, the silver-coloured filling containing mercury, lasts twice as long as other types when applied properly. Less than 10 per cent need replacing in 10 years. Composite fillings, which are white, frequently need replacing within five years. Other fillings, such as cermet cement and gallium, have high replacement rates. Porcelain and gold fillings last longer than composites.

Are there any drawbacks? Many people find amalgam fillings unsightly and they have been linked to health scares. But large-scale studies have found no evidence of health risks from mercury, apart from allergic reactions in very few people. A recent study comparing people complaining of amalgam-linked ill health with people who also had mercury fillings but no symptoms, found no difference between the amounts of mercury in their blood or urine, but discovered that more of those who complained of amalgam-related symptoms had histories of psychological problems. Out of caution, dentists prefer not to use amalgam in pregnant women.

What about the cost? Amalgam fillings will cost you least on the NHS and are by far the best value for money: they are three times cheaper than composites over 10 years. White fillings are only available on the NHS in front teeth where they show. You will have to pay privately for anything else, and fees vary between dentists.

So what's best? Your choice is between vanity or fewer trips to the dentist.

Thanks to guardian.co.uk who have provided this article. View the original here.