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Bacteriology Science Fair Project

Dental Retainer Bacteria and Cleaning Methods

Hard
Dental Retainer Bacteria and Cleaning Methods | Science Fair Projects | STEM Projects
Does brushing with toothpaste clean a dental retainer better than rinsing with mouthwash? Retainers sit against your teeth for hours and collect bacteria. The cleaning method you choose may make a big difference. Four participants wear their retainers for 24 hours under three conditions across three days. On day one, they only rinse with water (no brushing). On day two, they brush with toothpaste. On day three, they rinse with mouthwash. After each condition, you swab the retainers onto agar plates and measure bacteria growth after five days. Brushing with toothpaste cuts bacteria growth by more than half compared to no brushing. Mouthwash also helps but is less effective than toothpaste.

Hypothesis

The hypothesis is that there will be greater amounts of bacteria on dental retainers if they are worn without being regularly brushed with toothpaste.

Method & Materials

You will prepare 12 Petri dishes of agar, have 4 participants wear their dental retainers continuously for 24 hours without brushing their teeth, brush their teeth with toothpaste, rinse with mouthwash, and measure the size of bacteria growth using a ruler.
You will need 12 agar Petri dishes, 12 disinfected swabs, 1 bottle of disinfected water, 4 toothbrushes, sterile gloves, 4 participants who use dental retainers, 4 cups of water, 1 tube of toothpaste, 1 bottle of mouthwash, 1 marker pen and writing material.

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Results

The results showed that regular teeth brushing with toothpaste is able to reduce the amount of bacteria growth in the dental retainer. Mouthwash also reduces bacteria growth on the dental retainer, but is not as effective as brushing with toothpaste.

Why do this project?

This science project is interesting because it shows how important it is to brush your teeth and dental retainers regularly in order to maintain good dental hygiene.

Also Consider

Variations of this experiment could include testing different brands of toothpaste and mouthwash to see which are more effective, or varying the time allowed for the bacteria to grow.

Full project details

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

Related videos

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