Chester Zoo: Rico the sloth has toothache cured with ground-breaking dental treatment

A 25-year-old sloth at Chester Zoo has recovered from a pioneering dental operation performed by university dental experts, after staff noticed swelling on his face.

Rico, a two-toed sloth and one of the zoo’s oldest residents, was found to have two root abscesses during a series of check-ups last year.

The diagnosis led to an unusual collaboration with specialists from Newcastle University’s School of Dental Sciences.

The three-hour procedure took place at Chester Zoo’s on-site animal care centre.

One tooth was saved and both infections were stopped from spreading during what the team described as a “very challenging but rewarding experience”.

Dave Edwards, Clinical Fellow at Newcastle University and Newcastle Hospitals’ Dental Hospital, said:

“A three-dimensional scan showed that routine root canal treatment wouldn’t work. We instead carried out an apicectomy, where the root tip is removed and sealed.”

Unlike a standard root canal, the procedure involved entering through Rico’s jawbone, a complex process made more difficult by sloths’ unique anatomy.

Rico’s post-surgery X-rays have been clear, and keepers say his dental filling remains in place.

Charlotte Bentley, Veterinary Resident at Chester Zoo, explained: “Sloths have highly specialised molar teeth with sharp points. We wanted to avoid extractions if possible, as their teeth are vital for food processing.”

After the operation, Rico was monitored closely and has remained infection-free. He continues to take part in regular health checks, though, in true sloth style, he does so at his own pace.

Brittany Williams, part of the zoo’s Twilight Team, has been working with Rico for several years, using target-stick training and food rewards like cooked parsnips to encourage him to participate in health routines.

He can now be called down by name, stand still for weighing, and even hold his mouth open for inspections.

“Rico is very food motivated,” Brittany said. “Once he learns something, that’s it — he remembers. He’s great at recall and responds from anywhere in his enclosure.”

Sloths may look docile, but their long claws and strong teeth mean keepers must work with care. “You’re working without a barrier,” Brittany added.

“But Rico’s never swiped me — he’s a very good boy. He trusts me.”

Two-toed sloths like Rico are native to South America and face growing threats from habitat destruction and the illegal wildlife trade. Rico is part of Chester Zoo’s conservation breeding programme.

Fiona Beddis, Associate Clinical Lecturer at Newcastle, said working with Rico was “a once-in-a-lifetime opportunity”.

“I actually had the same surgery myself at 16,” she said. “So I had a lot of empathy for him — though Rico had much less swelling afterwards than I did!”

Beddis recalled getting a message from keepers a week later written from Rico’s perspective: “Good morning, Fiona and Dave. I’ve been very well behaved and eaten all my vegetables overnight… My face isn’t very swollen and I’ve taken my pain meds. Everyone is very happy with me.”

She added: “Having never carried out this procedure on a sloth, it really was a step into the unknown. We’re all delighted with the outcome.”