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Bacteriology Science Fair Project

Mouthwash Types and Oral Bacteria

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Mouthwash Types and Oral Bacteria | Science Fair Projects | STEM Projects
Does the type of mouthwash you use change how well it kills bacteria? Four mouthwashes with different active ingredients go head to head in this test. The brands include an antiseptic, a sodium fluoride, a cetylpyridinium chloride, and a zinc chloride formula. You swab the back of someone's tongue before and after rinsing. Each swab is wiped inside a marked circle on a petri dish. After four days, you count and compare the bacteria that grew. The zinc chloride mouthwash produced the least bacteria growth overall.

Hypothesis

The hypothesis is that the mouthwash containing sodium fluoride will work the best because it is an oxidizing agent, which kills bacteria and prevents more sulfur compounds from generating.

Method & Materials

You will swab the back of two people's tongues with cotton swabs, rinse their mouths with water, rinse their mouths with one of the mouthwashes, swab the back of their tongues again, and then compare the amount of bacteria grown four days later.
You will need a petri dish, four types of mouthwash, cotton swabs, and a marker.

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Results

The experiment showed that the zinc chloride mouthwash Lavoris had the least amount of bacteria growth and thus worked best. Further experimentation should use each mouthwash for two consecutive weeks instead of just once.

Why do this project?

This science project is interesting because it tests the effectiveness of different types of mouthwash against bacteria.

Also Consider

Variations of the experiment could include testing different concentrations of the mouthwashes or testing the mouthwashes on different types of bacteria.

Full project details

Additional information and source material for this project are available below.
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