dentistry in captivity
Protecting teeth in scores of species
It’s a Saturday morning and Dr. John Scheels, Dent ’75, is making a house call to check on his most troublesome patient. Niijii got himself into yet another fight, and he has a swollen mouth and angry gash across his nose to prove it. One tooth is cracked; another, infected. It’s just the latest insult to a mouth that has endured five root canals and numerous fillings.
When Scheels arrives at Niijii’s den at the Milwaukee County Zoo, the 85-pound wolf has already been darted with a tranquilizer. Niijii is gently strapped to a stretcher and whisked away to the Animal Health Center, where Scheels gets to work.
During the week, Scheels is an ordinary dentist who treats adults and children at his practice in Wauwatosa, Wis. But on his off-hours, he’s the dentist for scores of species at the Milwaukee County Zoo and Chicago’s Brookfield Zoo, where he performs root canals on polar bears, pulls infected teeth from lions, and mends broken beaks of exotic birds.
“It’s an avocation that’s become really rewarding,” he says.
Scheels is a leader in a small and highly specialized field. He’s an internationally known speaker on zoo dentistry who publishes articles and sits on the review board for the Journal of Veterinary Dentistry. He organized and co-chaired the first International Zoo/Exotic Animal Dentistry Conference and created the veterinary dentistry program for the University of Wisconsin-Madison School of Veterinary Medicine.
Scheels is modest about his accomplishments, but Milwaukee County Zoo veterinarian Vickie Clyde calls him “one of the top three zoo dentists in the world.”
Scheels chuckles when he hears the compliment. “Well, that’s pretty flattering coming from her. But there are probably only five or six of us who have this much
experience,” he admits.
On a Saturday morning in September, Scheels tends to two abscessed teeth for Bill, a spider monkey with big, doleful brown eyes. The 27-year-old primate is curled up in fetal position on a bright green towel. An IV drips into Bill’s furry, 13-pound body as the nearby heart monitor beeps regularly.
“This is major surgery for this little guy,” Scheels says. “I’m going to try to do as much as we can as fast as we can, and get it over with.”
Scheels is quick. Using a tool that resembles a screwdriver, he works at the edge of the tooth, a yellow nub slightly larger than the tip of a pencil. He twists the tool’s handle with the slightest flick of his wrist. Within five minutes, both infected teeth are out.
It’s not so easy with Niijii, the wolf. Scheels hates to remove a canine on a carnivore because it’s such a large and critical tooth. It’s also a tricky process: The root extends a couple of inches below the gum line, and if he’s not careful, he could fracture the wolf’s jaw.
When the first tool doesn’t work, he turns to forceps. “I don’t expect to get it out like this,” he says. “I think we’ll have to cut it out in sections, but I’m going to try.”
The tooth resists. Scheels turns to a drill to hollow out the tooth, the same technique he once used on a polar bear. “This is reminiscent of a person’s really difficult wisdom tooth extraction,” he explains.
Two hours later, Scheels is finished. “He’s going to be one sore puppy,” he says of the 5-year-old wolf, before prescribing a week of soft food as part of the follow-up care for his patient.
Scheels majored in zoology at the University of Wisconsin-Madison before coming to Marquette for dental school. About 25 years ago, he read a magazine article about a zoo dentist. Intrigued, he volunteered his services at the Milwaukee zoo, and soon found himself in a cage inspecting an orangutan’s broken tooth.
“The bulk of my time is extracting problematic teeth, but we run the whole gamut of problems,” says Scheels, who consults on about 50 cases a year.
There’s not always a precedent to follow. “If he can’t find the research he needs, he’ll go to paleontology records,” Dr. Clyde says.
Before Scheels, no one in the world had information about the roots of a gorilla’s teeth. Scheels filled that gap by getting permission to examine the skull of Samson, a gorilla that was the Milwaukee zoo’s most popular attraction for more than 30 years. To learn more about his wide range of patients, Scheels has also examined the skulls of a hyena, lion, koala and other animals.
He has developed relationships with other leaders in the field. Before working on a sea lion, he conferred with a friend at the London Zoo. Before treating carcinoma in a warthog, he consulted warthog experts in South Africa.
He has worked on roughly 80 species, from giraffes to porcupines, camels to fruit bats. Some jobs are more complicated than others: For example, it takes 10 people to move an 1,100-pound polar bear, and the Chicago zoo insists that someone stand guard with a loaded gun during the process.
Teeth are teeth, but exotic creatures present their own sets of challenges. Animals often try to hide their pain, and by the time they exhibit outward symptoms, the situation can be critical.
“Think about if you were working on a patient every day who can’t tell you what’s wrong. My human patients come in, and, if they have a problem tooth, they say, ‘Oh, it hurts right here.’ But my animal patients can’t do that,” Scheels says. “So it’s made me think about all those fundamental diagnostics.”
The zoo works hard to keep the animals healthy. But because zoo animals live longer in captivity than in the wild, some problems are unavoidable simply because of old age.
Zoo dentistry forces Scheels to get creative. He once used 2-by-4 blocks of wood to prop open the jaws of a rhino, and modified a wood chisel from a hardware store to clean the rhino’s teeth. He used tweezers to pull an infected tooth from a pygmy marmoset that weighed just 4 ounces, and a plastic ruler and dental cement to mend an African spoonbill’s broken bill. His experimentation even led to a patented mouth prop that’s now used with dogs and cats in veterinarian offices across the country.
His zoo work has also affected the way Scheels approaches his traditional practice.
“It certainly has given me a much more holistic perspective on dentistry, and I know it’s made me a better dentist,” he says.
For years, he worked at the Milwaukee zoo for free. He now charges just enough to cover his expenses and pay an assistant. In thanks for his work, the Zoological Society of Milwaukee lists Scheels among the highest level of its donors in the Platypus Society.
But financial rewards are the furthest thing from Scheel’s mind. He is fascinated by the field and honored by the unique opportunities. He feels an obligation to help keep these patients healthy.
“The animals are important to the whole community; they kind of belong to everybody,” he says. “And that’s why if we’re going to work with them, we’re going to do the best we can.”