Professor Philip Rood, Professor of Oral Surgery at King's College London, said the family dentist who had referred Darren Denholm for treatment had "fallen below the standards of a dental surgeon".

The eleventh day of a Fatal Accident Inquiry at Edinburgh Sheriff Court heard that dentist Bob Shields saw Darren, from Armadale, West Lothian, for his toothache on several occasions before his death.

Never regained consciousness

On his final visit to Mr Shields, when he referred the boy to Peffermill Clinic in Edinburgh, he neither examined the tooth nor explained about alternative treatment options.

Darren was referred for a single tooth extraction under general anaesthetic.

He never regained consciousness from the anaesthetic given before the treatment.

Professor Rood said: "Any reasonable dentist would be expected to at least make a judgement about the treatment option and if it involved an invasive procedure I would expect an explanation to be given to the patient.

"His intention before had been to save the tooth and he had prescribed antibiotics.

'Outrageous practice'

"I can't justify his actions on the last visit as to whether the tooth was treatable or untreatable."

The inquiry heard that Darren's parents were not told of alternatives remedies and it emerged that root canal treatment could have been used to save the tooth.

Professor Rood said evidence heard by the inquiry that anaesthetist Dr John Evans-Appiah told the dentist to go ahead with a local anaesthetic before the child was fully anaesthetised showed "outrageous" practice.

He said: "It's not something I would expect anyone to do.

"If a patient is moving and is inadequately anaesthetised the anaesthetist will say 'stop, and let me get control again'.

"I have never been in a situation where the anaesthetist has said 'I've lost control, you have a go'.

"If that was the case it was doomed not to provide the answer he was seeking."