A dentist accused of a series of blunders that led to 135 patients being recalled after fears they might have cancer has appeared before an independent inquiry.
Professor Philip Lamey faces 46 charges after four of his patients at the School of Dentistry at the Royal Victoria Hospital in Belfast died from cancer.
Concerns had been raised about the late diagnosis of cancer found in some patients, with 15 identified as cancer patients who may have had some delay in their diagnosis.
A hearing at the General Dental Council (GDC) on Monday heard how Professor Lamey faces 46 charges involving 33 patients.
David Bradly, counsel for the GDC, told the hearing how on one occasion Professor Lamey diagnosed an elderly patient, 'Patient Three', as having a traumatic ulceration of the tongue.
He repeatedly prescribed iron supplements to the 78-year-old, but eventually made a late diagnosis of squamous cell carcinoma (SCC) – a type of skin cancer – which "would not be healed by iron supplements".
He added: "Professor Lamey failed to review the diagnosis of trauma."
And he wrote in his notes that Patient Three declined a biopsy, when no biopsy was even offered to the pensioner.
The hearing also heard how Professor Lamey failed to follow up an initial diagnosis of trauma on four patients.
While treating another patient, named only as Patient Four, Professor Lamey diagnosed a traumatic mucocele in the upper lip, which can be a sign of a tumour on the salivary gland, but got a dental trainee to carry out the biopsy.
And the dentist caused "unnecessary delay" removing a patient's mercury fillings and prescribing antibiotics when Patient Five actually had lesions spreading through her mouth.
Mr Bradly said: "Medications were not going to work because this lesion was a tumour.
"This patient should have been referred for a biopsy. It was all an unnecessary delay."
The dentist's blunders also caused another patient to be rushed to hospital after a wrong diagnosis, the hearing heard.
Patient Six was told they had temporomandibular joint dysfunction (TMD), when she in fact had a tumour in her jawbone.
Mr Bradly said: "Professor Lamey gave a diagnosis of TMD and prescribed sugar-free chewing gum for treatment and said he would see her in three months.
"She actually had a tumour in the mandible and was admitted to hospital. She had a SCC and had radiotherapy following an operation."
The hearing, expected to take 19 days, will focus on seven mouth cancer patients who were wrongly treated by Professor Lamey, among others.
The hearing in central London continues.