A report has identified "serious deficiencies" in the quality of care provided by the Royal Dental Hospital in Belfast.
A full report into the oral medicine service at the hospital has been published by the Department of Health.
The inquiry was launched in 2011 after 117 dental patients were recalled for check-ups.
It followed concerns over the work of Professor Philip Lamey.
Prof Lamey is accused of 46 counts of malpractice involving 33 patients by the General Dental Council. He denies the allegations.
The summary of the report was published in June 2011.
The publication of the full report was delayed due to a number of regulatory processes not being complete.
The final report, led by Brian Fee QC, has been published by the department and a 42-point action plan has also been published to address the recommendations of the report.
Health Minister Edwin Poots said all the actions should be completed or ongoing by September 2014.
In a statement to the Assembly Mr Poots said: "This should not have happened and I want to ensure that it never happens again.
"This highlights that there were serious deficiencies in the quality of care provided by the Oral Medicine Department of the Dental Hospital and Belfast HSC Trust to the patients recalled, which did impact adversely on the health of some."
He added: "I hope that implementation of the action plan will help address the concerns that this incident has raised and that it improves public confidence in the Belfast Dental Hospital."
A spokeswoman for the Belfast Trust said it welcomed the report.
It said all of the actions within the action plan which were the responsibility of the trust are now being implemented.
"Belfast Trust regrets that a number of patients experienced care below the standard we would have expected.
"We have separately apologised to those patients.
"We also regret that anyone was caused undue anxiety as a result of being called back for further review."
Prof Lamey faces allegations that he prescribed iron tablets or sugar-free chewing gum to cancer sufferers after failing to spot they had the disease.
Dr Tony Stevens, the trust's medical director, said the issue came to light in December 2009, with "immediate concerns" over a number of patients.
In March 2011, then Health Minister Michael McGimpsey said two senior consultants reviewed 3,000 patients seen by Prof Lamey after a request by Dr Stevens, beginning in January 2010 and completed 10 months later.
While concerns were first raised in 2009, the trust waited 13 months before recalling patients who could be at risk.
Trust chief executive Colm Donaghy came under fire for failing to inform the Stormont health committee about the probe.
A misconduct panel dealing with Prof Lamey's case has been adjourned until October.