Getting to the root of Charlie's pain

Dr Bonnie McMeekin (front centre) of Auckland Zoo checks on Charlie's progress under anaesthetic. Photo / Greg Bowker

Visit to dentist proves labour-intensive operation for Auckland Zoo's oldest male orang-utan.

It took three vets, six nurses and two and a half hours to carry out a root canal on Auckland Zoo's oldest male orang-utan.

Charlie, 31, was recovering from the anesthetic yesterday afternoon after surgery to investigate and fill a 4mm wide by 25mm deep hole on a tooth double the size of a human's.

The hole in his upper-left incisor, the tooth used for biting, was spotted by the primate keepers when they were carrying out daily tests with the apes including getting them to open their mouths.

While he was inside the zoo's New Zealand Centre for Conservation Medicine, Charlie also had a general check-up and a small 8mm skin lump removed.

Specialist veterinary dentist Dr Russell Tucker and two nurses from Kohimarama Vet Clinic were brought in to carry out the straightforward dental procedure, which involved filing out rotten material in the dead tooth, cleaning it with sodium hypochlorite bleach before flushing it with saline. The hole was then filled with root canal cement similar to that used for humans.

"The purpose of the root canal is we are removing the infection but he ends up with a tooth he can still use, that's still in his mouth and still perfectly functional," Dr Tucker said.

Dr Tucker does an average of one root canal a day on a range of animals including dogs, cats and other animals from both Auckland and Hamilton zoos. He said Charlie would notice his tooth ache had disappeared in the next couple of days when he was chewing food.

Auckland Zoo senior vet in clinical services Dr Bonnie McMeekin said Charlie was recovering well in his den. "Within 45 minutes he was standing up ... He knows something has happened, he knows he's been affected by drugs, I'm not aware if he knows why."

Dr McMeekin said dental issues in zoo animals were not uncommon and root canals were most often carried out on the large cats with snapped canines.

Meet Charlie:

Weight: 96kg
Strength: 5 to 8 times stronger than human male
Age: 31
Teeth: 32 (same number as humans)
Son: Madju, age 7
Two female companions: Melur and Wanita
Born: Singapore Zoo
* Up to 45,000 Bornean orang-utans left in the world.
* Life expectancy in captivity up to 60 years.
* Six at Auckland Zoo.
* Cost of orang-utan root canal between $1400 and $1600.