Only about half of the population in England is registered with a surgery so ministers are freeing up dentists' time by changing the way they work.

What is the problem?

Last year, there was a shortage of 1,850 dentists. At the moment just 17m adults and 7m children in England - about half the population - are registered with a dentist.

In some places, dentist surgeries have stopped taking on new patients as their lists are full.

It is not known exactly how many people have been denied access but it is clear action is needed after images of people queuing to register with dentists have been regularly featured in the media over recent years.

How is the government tackling the problem?

Ministers are reforming the way NHS dentistry works.

From October 2005, primary care trusts are being given responsibility for commissioning dentists to do work.

Instead of being paid for each NHS treatment they carry out, dentists will be given a guaranteed income based on their historical income - estimated to be in the region of an average of �69,000 a year - for three years for providing services to the local community.

It will mean dentists will no longer have to carry out treatment to be paid - a situation which led some to claim dentists were over-treating their patients.

Under the plans, dentists will be expected to spend more time addressing preventative measures.

This will mean they will be freed from time-consuming treatment and, theoretically, treat more patients.

On top of that, the government wants to recruit an extra 1,000 dentists by the time the new arrangements come into place.

Will patients have to pay more?

Perhaps. At the moment NHS patients currently pay 80% of the fee up to �378, although some patients, such as those on benefits, are exempt.

One of the criticisms of the current system is that patients often have no idea of how much the treatment is going to cost until it is finished.

Details of the new arrangements have not been published yet but the government says it wants to introduce a simpler system.

It is widely expected to be based around a band system, meaning some patients could pay more while others pay less.

Will all dentists sign up to the reform programme?

There are 19,300 dentists working in the NHS either under the General Dental Service or Personal Dental Service contract.

The new arrangements will replace both systems and while dentists are not compelled to sign up to it - they work as independent contractors - the government is confident most will.

However, the National Audit Office has warned dentists may reduce their NHS commitment as they are sceptical about the plans.

So will the changes make a difference?

The government hopes so but there are some concerns.

The NAO has said primary care trusts do not have the necessary expertise.

And a poll by the British Dental Association found just one in 10 dentists had confidence their PCT could cope with their new responsibilities.

There are also suggestions that as dentists will not be compelled to treat more patients - it will be left to the PCT to negotiate this - some may just stick to treating their current patients safe in the knowledge that their income is protected for three years.