Project Summary

Do drinks with different pH levels damage tooth enamel in the same way? This experiment investigates how acidic beverages affect dental enamel using eggshells as a model due to their calcium carbonate composition. Different liquids with varying pH levels, such as water, orange juice, soda, and vinegar, were tested by immersing eggshell samples and observing changes over time. The results showed that more acidic solutions caused greater erosion, making the shells thinner and more porous. Overall, the study demonstrates that frequent exposure to acidic drinks can damage enamel and highlights the importance of protecting dental health.

Why did you do this project?

We did this project because many students regularly consume acidic drinks like soda and citrus juices without realizing the potential harm to their teeth. Since this is a common daily habit, we wanted to understand better how these beverages might affect dental enamel. By investigating this, we aimed to raise awareness about oral health and encourage hygiene habits. Additionally, the topic is practical, relevant, and easy to demonstrate using accessible and ethical materials.

How did you make your project or solve this problem?

Eggshells were selected, washed with water, and left to dry completely overnight.  Fragments of approximately 1.5 g were cut. The eggshells were observed under a microscope (40x) to record their initial condition. The pH of each liquid (water, orange juice, soda, and vinegar) was measured using pH strips. Eggshells were placed in each solution and changes were observed at 15 and 30 minutes. After 1 hour, the samples were removed and left to dry for 5 hours. The eggshells were analyzed again (color, porosity, and hardness) and compared to their initial condition.

What did you find out?

The experiment showed that acidic drinks do damage the eggshells, which models dental enamel. The vinegar had the strongest effect, producing bubbles almost immediately and dissolving part of the outer layer. The soda also caused noticeable changes, but more slowly, while the orange juice had a milder effect. In contrast, the water caused almost no change, confirming that lower pH (more acidic liquids) leads to greater erosion.

Why do your results matter?

The results matter because they show that everyday drinks can gradually damage dental enamel, even if the effects aren’t immediately visible. This is important since many people consume acidic beverages regularly without realizing the long-term impact. By understanding how acidity (pH) relates to enamel erosion, we can make better choices to protect our teeth. It also highlights simple preventive actions, like reducing intake of acidic drinks or rinsing with water afterward, to maintain good oral health.

What could you do next?

We could improve the project by making it more precise and closer to real-life conditions. For example, by testing more beverages (like energy drinks or sports drinks) to compare a wider range of pH levels. Increasing the sample size and repeating the experiment several times would make the results more reliable. Measuring dry weight before and after exposure could also provide stronger results.

Another improvement would be extending the exposure time or testing repeated short exposures to better simulate how people actually drink beverages.

References

- Saads Carvalho T, Lussi A. Chapter 9: Acidic Beverages and Foods Associated with Dental Erosion and Erosive Tooth Wear. Monogr Oral Sci. 2020;28:91-98. doi: 10.1159/000455376. Epub 2019 Nov 7. PMID: 31940633.

- National Health Service (NHS) – How to Keep Your Teeth Clean

- Britannica – Calcium Carbonate

- Sciencing – What Are the Similarities Between Eggshells and Teeth?

We would like to thank Miss TG for her guidance and support throughout the experiment. Her explanations and assistance helped us better understand the process and complete our work successfully.