By Michelle Roberts
BBC News health reporter
Children can be afraid of going to the dentist
Filling rotten baby teeth may be an unnecessary trial for children to endure, experts say.
Some 40% of five-year-olds in the UK have tooth decay and at least one in 10 of these is treated with fillings.
But anecdotal evidence from 50 dentists gathered by Manchester University researchers suggests filling baby teeth may not offer significant benefits.
Advisers to the NHS are now beginning a study on treatment options to provide dentists with clear guidelines.
Experts already know there is wide variation in care which means that a young child with signs of tooth decay could have no treatment, a filling or the tooth pulled out depending on which dentist they attend.
Without any clear guidelines, dentists currently have to rely on their experience and judgement to decide whether or not to intervene.
If the child is in severe pain and having sleepless nights, and the parent is confident that their child will cope with and benefit from the treatment, then the choice may be clear.
But when the decay is not causing symptoms, it can be difficult to decide what is in the child's best interests given that their tooth will ultimately fall out by the time they are 11 anyway.
Indeed, anecdotal evidence gathered from the case notes of 50 dentists suggests filling baby teeth may achieve nothing but expose children to the discomfort of an injection and the sound of the drill.
Professor Martin Tickle, of the University of Manchester, found no difference in the numbers of extractions for pain or infection whether baby teeth had been filled or not.
And when he surveyed the parents of all five-year-olds living in Ellesmere Port and Chester in 2003, he found only 6% would want their child to have a filling if they had symptomless decay in a baby tooth.
In comparison, a third would want the dentist to monitor the tooth but provide no treatment.
Experts working for the Health Technology Assessment Programme plan to recruit over 1,000 children from across the UK to take part a study that will compare the outcomes of three treatment options.
They are conventional drilling and filling, no fillings or a painless paint-on tooth treatment that merely seals and contains the decay.
Lead investigator Dr Gail Topping, of the University of Dundee, said: "This is a really big question to answer.
"At the moment there is no clear winner and we do not know which is best to recommend. There is no guidance or mandate.
"At the moment, dentists are doing what they believe is the right option for the child on a case by case basis."
She said dentists would welcome evidence-based guidelines because the treatment decision can be a difficult one to make.
Kamini Shah, dentist and honorary secretary of the British Association for the Study of Community Dentistry, said: "There are two schools of thought, one being that baby teeth can cause pain and sleepless nights and so dentists should fill.
"The other is that actually the evidence around filling baby teeth is questionable.
"Speaking from a personal view point, sometimes you need to adopt a pragmatic approach rather than go in with all guns blazing.
"If a child is very uncooperative but has a mouthful of non-symptomatic holes you might decide to apply a fluoride varnish to stabilise the disease rather than to do conventional fillings."
Painted on with a small brush, the banana-flavoured varnish is totally painless and can slow or even stop the decay if applied often enough.
Sophie Waller had an extreme phobia of dentists, an inquest was told
Dr Shah said: "That way you gain the child's confidence and can work on prevention. You do not want to upset the child and make them phobic of future treatments.
"The problem arises when children come in aged three or four and it is their first experience of the dentist and it is because they are in pain.
"In that scenario you can well imagine that they might not be most cooperative."
She said in extreme cases, and when the decay was so bad it necessitated treatment, a child might be referred for anxiety management or have the teeth removed under general anaesthetic.
Recently, an eight-year-old girl starved to death because of an apparently severe dental phobia.
Sophie Waller, from St Dennis in Cornwall, is thought to have been so traumatised by her phobia that she refused to open her mouth after having eight teeth removed under general anaesthetic.
The full trial will run for four years from 2011 across England, Scotland and Wales, with a feasibility study starting in the coming months.