A New Plymouth dentist has been charged with professional misconduct and ordered to pay $26,000 in fines and costs.

Dr Peter Liston, a dental practitioner of 34 years practising as an oral and maxillofacial surgeon in the Whanganui area, was charged with five counts of misconduct following a hearing by the Health Practitioners Disciplinary Tribunal.

The hearing was held in Whanganui on December 6 and 7 last year.

It addressed 12 consultations Dr Liston had with a patient, Keith Hindson, between December 2011 and November 2013. This was regarding concerns relating to Hindson's tongue.


During that period three biopsies of Hindson's tongue were taken, including two excisional biopsies.

The Tribunal found Dr Liston did not act correctly on the biopsy results and failed to recommend or provide treatment appropriate to the biopsy results.

Nine months after the first biopsy results, Hindson was referred to the Palmerston North Hospital Dental Clinic and told that he had cancer, requiring surgery.

A charge was laid against Dr Liston under the Health Practitioners Competence Assurance Act 2003.

That charge included Liston's failure to recommend or provide re-excision of Hindson's tongue, failure to recommend referral to a multidisciplinary team for review, failure to recommend or undertake no less than six-weekly monitoring, and failure to adequately inform Hindson of his diagnosis.

The charge also included Liston's failure to explain to Hindson where his diagnosis fitted in the spectrum of disease process, to take appropriate steps to ensure Hindson understood what his treatment options were, and to ensure Hindson understood what the risks associated with not re-excising his tongue were - for instance becoming invasive cancer.

Liston was also charged with failing to keep clear, detailed and accurate clinical notes.

Tribunal Chairperson David Carden said Liston's actions were "unquestionably negligence" and brought discredit to the dental profession.


"While biopsy results showed abnormal cells were present, Dr Liston told Mr Hindson that the biopsy showed 'nothing nasty', and advised him that the condition was dysplasia and definitely not cancer," the report stated.

"That was clearly wrong and is now acknowledged by Dr Liston as wrong."

The charge and its particulars were found to warrant disciplinary sanction, the report said.

The Tribunal ordered that Dr Liston pay a fine of $5000, and to pay a contribution towards costs totalling $21,000 to be divided equally between the Director and the Tribunal. It also ordered the censure of Dr Liston.

Although suspension and supervision were also considered, Carden said the Tribunal did not consider this was required.

"The Tribunal accepts that this is a one-off situation and that there is no evidence that Dr Liston has failed to perform his obligations as an oral and maxillofacial surgeon or dental practitioner in any other respects," the report said.


The Tribunal applied significant allowance for pressures and stresses Dr Liston was under and the limited resources that he had available to him.

"The evidence of Dr Rawlinson was helpful in pointing to the pressures and stresses that he was under," the report stated.

"He described the dental unit at Whanganui Hospital as a small space and a very busy unit. He described staffing numbers and staffing shortage difficulties.

"There is to be taken into account too the important role that Dr Liston is fulfilling in the community by being the only oral and maxillofacial surgeon practising in Whanganui. Any suspension of him would deprive the DHB and the public of the services that he can offer."

This information led the Tribunal to recommend that the DHB put in place such resources and facilities as it can to enable Dr Liston to have an active engagement in clinical audit and review processes with a surgical group in the DHB.

It also recommended that Dr Liston be afforded such non-patient-contact time as can reasonably be provided so that he may actively review patient records, reports and test results to ensure appropriate patient treatment and management.


"Evidence suggesting that Dr Liston had limited hours in the hospital and was required to do this type of work in his own time at home only serves to underline the inadequacy of resources there were for him to discharge his responsibilities," the report said.

Dr Liston has had only one other complaint against him relating to the deciduous extractions which was resolved with no further action being taken.

During the hearing in December, Dr Liston apologised to Hindson.

"I appreciate you have had a long, hard journey. I am sorry for the problems it has caused you," he said.

Dr Liston's lawyer Hannah Stuart said he expressed sincere regret and remorse for his mistake.

"Dr Liston did not choose not to provide this information to the patient. He misread/misinterpreted the histology results as showing Hindson's condition as more benign than it in fact was.


"It was an inadvertent error, not a choice on Dr Liston's part, which occurred in the context of a significant shortage of resources at the DHB. It is self-evident how these mistakes can happen," she said.