How much tooth enamel does the phosphoric acid in soda dissolve? Dentists already use phosphoric acid to etch teeth before bonding. The same acid is an ingredient in drinks like Coke and Pepsi.
You soak fifteen wisdom teeth in five different strengths of phosphoric acid for seven days. The weakest solution is plain water (the control). The strongest is double the acid level found in commercial soda. You weigh each tooth before and after soaking to measure the enamel lost.
The teeth in the strongest solution lost the most weight. Higher acid concentration meant more enamel dissolved.
Hypothesis
The hypothesis is that if the concentration of the mixture is stronger, more tooth enamel will be lost.
Phosphoric acid is strong enough that dentists already use it to etch teeth before bonding — and the same acid is an ingredient in commercial soda. You soak fifteen wisdom teeth in five different concentrations of phosphoric acid for seven days, then weigh each tooth before and after to measure how much enamel dissolved. The teeth in the strongest solution lost the most weight. Higher acid concentration meant more enamel broken down and carried away.
As acid concentration rises, so does the rate at which it eats away at a solid material. Soaking wisdom teeth in five different strengths of phosphoric acid puts this directly to the test. The strongest solution dissolves the most enamel. Weighing each tooth before and after reveals exactly how much material each concentration ate away.
Method & Materials
You will autoclave teeth, weigh them, mix different levels of phosphoric acid solutions, and leave the teeth in the solutions for 7 days.
You will need 15 wisdom teeth, 1 can of Pepsi, 1 can of Coca-Cola, 1 pH meter, 1 MagneStir Mixing bar, 1 analytical balance, 1 drying oven, 1 vacuum oven, 1 autoclave, 1 desiccator, and all safety clothing.
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The results of the experiment showed that when the solution with the most reactant (solution/ group # 5) was tested against the teeth, more tooth enamel was etched away, compared to the solutions/ groups or one or two. Also the teeth in Group 5 weighed less than the teeth in Group 2.
Why do this project?
This science project is interesting and unique because it tests the effects of phosphoric acid on tooth enamel, which is an important factor in understanding how soda can affect teeth.
Also Consider
Variations to consider include testing different types of soda, testing different concentrations of phosphoric acid, and testing different lengths of time for the teeth to be in the solutions.
Full project details
Additional information and source material for this project are available below.
