An 8-year-old girl suffered profuse bleeding and vomited blood after a dentist performed a tongue-tie release on her that haemorrhaged two weeks later.
The girl required emergency care and surgery to stop the bleeding and now has restricted tongue movement.
She might require plastic surgery to treat the scar tissue left by the $1000 procedure.
Her story came to light after the Herald revealed complaints about an Auckland dental clinic where a dentist oversees orthodontic treatment but no one at the clinic is a specialist orthodontist.
The girl's procedure, known as a lingual frenectomy, was done at the same clinic where five children had years of orthodontic treatment that needed correcting.
The Herald is not naming the clinic.
The youngster's mother, who wants to remain anonymous to protect her daughter who is now self-conscious about the damaged tongue, wants the clinic to stop performing the tongue-tie releases.
She now believes all lingual frenectomies should be referred to ear, nose and throat [ENT] specialists.
"I felt so stupid," the mother said. "I totally harmed my kid."
A tongue-tie release suggested for the girl by staff at the clinic was initially ignored by her parents.
"We did not think it was a problem as we thought it was only a problem when babies cannot breastfeed," the mother said.
But she says a dentist at the clinic told her the "muscle of the tongue and the lip was too big" and pushing the teeth outwards.
He recommended a frenectomy, a procedure that releases the frenulum - the small folds of tissue beneath the tongue and between the top lip and the gum.
"I did it because he told me to do it and I thought he was the orthodontist and I thought it was a problem for her teeth," the mum said.
"We were not informed of potential risks involved. It was supposedly like every other routine dental procedure."
She thought the dentist was an orthodontist because he oversaw the specialist treatment.
Another dentist at the clinic performed the laser procedure along with the removal of a baby tooth for a cost of $1250 in late January.
Two weeks later, on February 13, the wound haemorrhaged and the girl's parents rang a public nurse who advised them to go to hospital if the bleeding didn't stop.
When it did stop at home the girl had to stay awake another hour and was not allowed to sleep on her back because of the risk of suffocation from blood clots.
"It was a bit traumatic. She thought she was losing her tongue."
The mother took the girl to her GP the next day who offered a referral to an ENT specialist.
According to a complaint the mother has lodged with the clinic, the Dental Council and the Health and Disability Commissioner, the family went back to the dental clinic first.
She claims the dentist who performed the tongue-tie release said there was no need to see an ENT specialist, that he was comfortable managing the complication and he didn't think it would haemorrhage again.
Two nights later the girl awoke to profuse bleeding again and her parents took her to Starship hospital's emergency department.
She was diagnosed with a bleeding frenulum haematoma and required surgery to stop the haemorrhage.
The tongue also curled to the side in an abnormal way and it's possible the girl will need plastic surgery.
The mother said her daughter can no longer reach her teeth or upper lip with her tongue.
ACC accepted the haemorrhage as a treatment injury but the mother said in the complaint that despite a text message to the dentist on the night her daughter was haemorrhaging again, she never heard back.
"We were not contacted by the dentist or any other [clinic] team member to inquire what had happened or how our child was doing.
"The only communication we received was a repetitive stream of appointment reminders."
The family told the clinic they would not continue there and received no response.
The senior dentist at the clinic was on holiday when the Herald questioned whether it was possible a frenulum could push teeth out of shape.
Through his lawyer, Harry Waalkens, QC, the dentist said it was inappropriate and unprofessional to comment publicly on patient cases.
However, Waalkens said the dentist would co-operate fully with any Health and Disability Commissioner inquiry.
In a response on Tuesday to the mother's complaint, a staff member at the clinic wrote: "It is obviously very disappointing to receive your letter as we pride ourselves in our customer care.
"I will need to do some investigating and come back to you once I have all the relevant information."
The Dental Council said frenectomies were an advanced area of practice and not part of undergraduate training for dentist registration.
"However, dentists are trained to treat conditions of the orofacial complex and can gain training and experience in tongue-tie release procedures at any time throughout their career."
It's unclear if the dentist who performed the tongue-tie release had the required training because no record is kept by the Dental Council.
The president of the New Zealand Association of Orthodontists, Dr Kieran O'Neill, said a frenulum pushing teeth out of shape would be "extremely rare".
O'Neill said he referred patients with a tongue tie to an oral surgeon, and that a tongue-tie or lip-tie release would usually be done during treatment, not before.
An orthodontist, who did not want to be named, said he had never associated a frenulum with affecting teeth, only breathing and tongue movement.