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How can sharks help us keep our teeth clean?

Dunedin schoolchildren have been getting their teeth into the science behind dentistry by exploring how animals bite and chew.

Primary and secondary school children in Dunedin, including relocated refugees, have been taking impressions of animal teeth and creating their very own plaster-cast model tooth to keep.

Carolina Loch, project lead and Lecturer at the University of Otago’s Faculty of Dentistry, tells us that she and her colleagues Richard Cannon, Paul Brunton and Neil Waddell started the project because they wanted to make dental health fun.

“People are a bit sick of hearing the same messages like ‘you need to brush your teeth’,” she says. “The kids are quite interested in different types of animals, dinosaurs and those kind of things, so we thought we could use this to get the health messages across in a fun, science-y, hands-on way.”


Carolina enlisted the help of three PhD students at Otago University, and the team visited five schools across Dunedin. They used real animal skulls and teeth to understand the differences between cows, dolphins, dogs and many other animals – as well as how they are different from ours.

“For example, we showed them that sharks have a ‘conveyor belt’ of teeth that are continuously getting replaced,” Carolina explains. “They have several rows of teeth and approximately every six months they get new ones. In that sense, sharks are lucky because they can just replace their bad teeth, unlike us.

“Other animals like dogs and sheep don’t have our decay and cavity problems as much because they don’t eat lollies and fizzy drinks.”

The highlight for the students was getting to take an impression of their favourite animal tooth, using the same materials our dentists use, and then pouring plaster into the impression to make a replica model of the tooth that they could take home.

“We used this to talk about why dentists take impressions and show them the fun things you can do as dentist - because normally when you think about going to the dentist you think about pain, drilling, horrible noises and so on,” Carolina says.

making impressions

Science without borders

Two of the schools – Carisbrook and Brockville – were also attended by children of Syrian refugee families who had relocated to Dunedin only six months ago.  By sheer coincidence, all three of the dentistry PhD students in the team – Shaikhah Al Samahi, Amira Salem and Ghassan Idris – are from the Middle East and speak Arabic.

“One teenage student from Carisbrook School, called Ahmed, had an appointment with his dentist on the same day as our activity and he told us that this activity was the best ever!” says Shaikhah, who is from the United Arab Emirates. “When we visited his school for the second time, he told me he’d painted the tooth model he made last time and he now keeps it in the living room on the top of the TV unit!”

Ghassan is from Syria and came to New Zealand in 2013 to pursue his PhD in Orthodontics.

“I actually have a personal connection with the majority of the Syrian families since they arrived in Dunedin last year and I have met many of them on different occasions,” he says. “I’m part of a social club called the Otago Syrian Association, which was set up by a group of Syrian former refugees in Dunedin to enhance good relations among the Syrians and the community in Dunedin.

“Many of the refugees now call Dunedin their new home after a tough experience being refugees in other countries. It is always hard to change your home, but it is good to land in the right place at the right time. It’s a new environment but it is warm and safe.”

Teeth and skulls

Amira can also empathise with the refugees’ experience of moving to a new country because she travelled here from Egypt to do a PhD investigating the bacteria that cause root canal treatments to fail.

“I was really anxious before I came here because it’s not easy to leave my family and friends and come all this distance so far from home, knowing no one in the whole continent. But the people here are so friendly, and it’s a great opportunity to make new friends and to be exposed to different cultures.

“The refugee children are trying hard to interact with other children in the schools but are struggling to understand what is being said in English. They do interact a little bit for sure and they do have some friends, so I think they just need more time.”

Carolina adds, “One of them knew English better than the others and acted like a translator between the Arabic and English vocabularies. So for those students, the activity was also a way of getting new vocabulary in English as well.”

Back by popular demand

young students at TKKM Otepoti

The thing that stands out most is the students’ enthusiasm. Carolina tells us that they try to visit most schools twice, and they found that the second time nearly always had double the number of participants because the first session was so well-received.

“One school, Te Kura Kaupapa Māori Ōtepoti, was quite special for me because some of the four and five -year-olds saw what the older kids had been doing and kept asking us if we were going back to do it again! I also learnt a lot because they taught us the animal names in Māori and how to say teeth and other words, which I really enjoyed.”

Shaikhah adds, “I am really grateful to the Te Kura Kaupapa Māori schools who showed us some cultural aspects that I hadn’t experienced before and liked very much. This school really was like one big family and the students were so creative.”

Tiahuia Kawe-Small, Tumuaki (principal) at Te Kura Kaupapa Māori o Ōtepoti, returns the sentiment: “This was an awesome workshop. The team worked well with our students and appreciated our use of te reo Māori and customs. It was also really great for our girls to see female role models as scientists.”

“I loved it so much and could not stop touching everything!” says one of the girls from this school.

Another student, an 11-year-old girl from Carisbrook School, commented, “It was awesome – I have always wanted to be a dentist!”

Watch the videos used in the activities here

Amira, Carolina, Shaikhah and Ghassan

Photo credits: the project team.

About the project

Uni Otago logoMaking a good impression: from fossils to false teeth is supported by the Unlocking Curious Minds contestable fund.



Unlocking Curious Minds

Unlocking Curious Minds supports projects that excite and engage New Zealanders who have fewer opportunities to experience and connect with science and technology.

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