Does the most expensive toothpaste clean the best? You stain 60 tiles for two days using five common staining liquids. Then you scrub each tile with one of five cleaners and compare the results.
The cleaners range from store-bought toothpastes to homemade baking soda formulas. Each tile gets exactly 25 brush strokes with one quarter teaspoon of product. An unstained tile for each cleaner serves as the baseline.
The priciest whitening toothpaste removed the most stains. The cheapest homemade formula did not clean as well.
Hypothesis
The hypothesis is that baking soda, salt, hydrogen peroxide, and water will be the best stain remover.
Color from a liquid soaks into a surface and stays, that is staining. In this experiment, 60 tiles are soaked in five common staining liquids for two days. Then five cleaners go head-to-head: store-bought toothpastes versus homemade formulas built from baking soda and water. Each tile gets exactly 25 brush strokes with one quarter teaspoon of product.
Toothpastes use abrasion, a rough surface scraping and wearing away a softer one through rubbing, to remove stains. You stain 60 tiles for two days using five common staining liquids, then scrub each tile with one of five cleaners. Each tile gets exactly 25 brush strokes with one quarter teaspoon of product, so the rubbing action stays constant while only the cleaner changes. The priciest whitening toothpaste removed the most stains.
Method & Materials
You will soak and stain 60 tiles for 2 days, then clean each tile with five different cleaning agents.
You will need Crest, Rembrandt, Mentadent, baking soda, salt, hydrogen peroxide, water, glycerin, and wintergreen.
Tinker Crate — science & engineering build kits for ages 9–12 — real tools, real experiments, delivered monthly. (Affiliate link)
The results showed that Rembrandt was the most effective stain remover, although it was the most expensive. Formula #1 was very inexpensive, but it did not clean teeth as well as Rembrandt.
Why do this project?
This science project is interesting because it tests different cleaning agents to see which one is the most effective for removing stains from teeth.
Also Consider
Variations to consider include testing different types of toothpaste, or testing different types of stain removers.
Full project details
Additional information and source material for this project are available below.
