DAYA: Monitoring and enhancing kids’ dental health

We designed a system to monitor and enhance children’s dental health for CHI design competition. We were selected into the final round and invited to Toronto to present the work.

The problem

Good oral hygiene habits are critical to preventing oral disease, which can be lifelong conditions and cause significant financial loss in families. However, our research revealed that in China, the efficacy of tooth-brushing remains to be improved:

  • 78% of 5-year-old children brush their teeth less than twice every day;
  • 20% of children do not brush their teeth daily.


To understand the root cause, we conducted user researches with kids and their parents.

Research questions

  • What is kids’ tooth-brushing behavior like?
  • What is the root cause of the inefficacy?
  • For kids: What do kids think about tooth-brushing? How much are they educated about it?
  • For parents: Are parents aware of the problem? How much do they educate their kids about it?


Key takeaways

Design process

Looking for inspiration

While we were doing the research, we also collected a bunch of inspirations from:

  • Academic paper
  • Fitness apps
  • Game design
  • Smart toothbrush patents.
We were heavily inspired by Nakajima et al.'s research that associates toothbrushing with cleaning a virtual aquarium. This inspired us to think about gaming as a mechanism of teaching.


As we started brainstorming solutions, we sketched our ideas to take down these ephemeral sparkles in our minds. Two directions quickly emerged: One is a parents' monitoring app, and the other is teaching toothbrushing with a game. We decided to explore both directions as neither is dispensable in solving the problem.

Brainstorm sketches

Prototyping the game

We explored the different types of games we might possibly design, and the idea of teaching toothbrushing with a tower defense game quickly stood out because it was almost a natural metaphore — the medical field is dividing teeth into regions, while tower defense games naturally have the concept of routes.

To test kids' understanding of the concept, we made a paper prototype for the game and tested with our users using Wizard of Oz method.

Paper sketch of the game components for Wizard of Oz testing

In the validation tests, we found that older kids (8 to 10 yo) understood the game better and made fewer mistakes than younger ones (6 to 7 yo). Thus we decided to enable adjusting the difficulty of the game according to children’s age.

Testing the protoype with kids

Prototyping parents' app

We made a pdf prototype of the app and presented it to parents.

Parents' app screens

One thing we found was the parents were interested in learning the correct toothbrushing techniques. Thus we decided to show the regional toothbrushing data in the detail section instead of in a modal to fit in the gif of the technique.

Another finding was that parents have different habits of changing the bristle. So we decided to give users more freedom in customizing the notification.

Finalized design

Stay informed

  • Track data on how much time your kids brush their teeth
  • Gain insights on which area is unattended
  • Compare performance with peers
  • Get reminders when it's time to brush their teeth

Gain insights by region

  • Quickly recognize the least attended parts
  • Get instructions on how to brush correctly

Manage profiles

  • Easily create profiles for family members
  • Track dental habits of everyone you care about

Learn to brush with game

  • Each stroke becomes meaningful and enjoyable as a bullet to defend the monsters attacking the castle
  • Track and guide region coverage, technique, and brushing duration with accelerometers
  • Collect tooth-brushing patterns for the monitoring app

Team and my role


Jiye Huang, Huaying Song, Runze Li, Jinxi Wu

My role

I led in the user research in designing DAYA. I reviewed paper on research methods and oral hygiene education, conducted surveys and observation, synthesized research findings, participated in design reviews, and wrote the final paper submitted to CHI.