Toothpaste Brand vs. Toothpaste Brand vs. Bacteria in your mouthBacteria in your mouth

By: Nick MerrimanBy: Nick Merriman

Question:Question:

How does the brand of toothpaste you use How does the brand of toothpaste you use (Prevident 5000 Plus, Pepsodent, Tom’s of (Prevident 5000 Plus, Pepsodent, Tom’s of Maine All Natural Organic) affect the Maine All Natural Organic) affect the number of bacteria on your teeth when number of bacteria on your teeth when brushing for 2 minutes in the morning with brushing for 2 minutes in the morning with the same toothbrush.the same toothbrush.

Hypothesis:Hypothesis:

If you change the brand of If you change the brand of toothpaste you use then the toothpaste you use then the Prevident 5000 Plus will remove Prevident 5000 Plus will remove more bacteria than Pepsodent or more bacteria than Pepsodent or Tom’s because it is prescription Tom’s because it is prescription strength toothpaste. strength toothpaste.

Toothpaste BrandsToothpaste Brands

VariablesVariables

Manipulated: brand of toothpasteManipulated: brand of toothpaste Controlled: amount of time brushing Controlled: amount of time brushing

(2 minutes), type of toothbrush, (2 minutes), type of toothbrush, amount of toothpaste used (1 amount of toothpaste used (1 squeeze), time of day (morning)squeeze), time of day (morning)

Responding: number of bacteria Responding: number of bacteria colonies on your teethcolonies on your teeth

MaterialsMaterials

Prevident 5000 Plus: Dry MouthPrevident 5000 Plus: Dry Mouth PepsodentPepsodent Tom’s of Maine Natural OrganicTom’s of Maine Natural Organic 6 sheep blood agar culture plates6 sheep blood agar culture plates 6 sterile swabs 6 sterile swabs 6 sterile inoculating loops 6 sterile inoculating loops toothbrush toothbrush timertimer

MaterialsMaterials

ProcedureProcedure Step 1-On the first day when you wake up note the time Step 1-On the first day when you wake up note the time

and brush your teeth for 2 minutes with Prevident 5000 and brush your teeth for 2 minutes with Prevident 5000 PlusPlus

Step 2-Use the sterile swab to go over your top teeth and Step 2-Use the sterile swab to go over your top teeth and your bottom teethyour bottom teeth

Step 3-Using the swab, make a circle on the blood agar Step 3-Using the swab, make a circle on the blood agar about the size of a quarterabout the size of a quarter

Step 4-Using the sterile loop spread a streak through the Step 4-Using the sterile loop spread a streak through the circle area you swabbed , and continue spreading the circle area you swabbed , and continue spreading the material out in 3 different directions on the plate. This will material out in 3 different directions on the plate. This will let you see and be able to count the separate colonies of let you see and be able to count the separate colonies of bacteria.bacteria.

2 minutes is a long time…..2 minutes is a long time…..

Swabbing for the cultureSwabbing for the culture

Inoculating the agarInoculating the agar

Procedure continued….Procedure continued….

Step 5: Place the blood agar culture in an incubator for 32 Step 5: Place the blood agar culture in an incubator for 32 hours at 37 degrees Celsius (body temperature)hours at 37 degrees Celsius (body temperature)

Step 6: Count the number of visibleStep 6: Count the number of visible

Bacterial colonies growing on the plate and record.Bacterial colonies growing on the plate and record.

Step 7: On the second repeat steps 1-6 for trial #2Step 7: On the second repeat steps 1-6 for trial #2

Step 8: On the third and 4Step 8: On the third and 4thth day repeat steps 1-7 with day repeat steps 1-7 with PepsodentPepsodent

Step 9: On the fifth and sixth day repeat steps 1-7 with Step 9: On the fifth and sixth day repeat steps 1-7 with Tom’s of MaineTom’s of Maine

32 hours later…….lots of bacteria32 hours later…….lots of bacteria

Experimental DataExperimental DataNumber of Bacterial Colonies on CultureNumber of Bacterial Colonies on Culture

(cfu = colony forming units)(cfu = colony forming units)

Trial #1Trial #1 Trial #2Trial #2 AverageAverage

PrevidentPrevident50005000

1337 cfu1337 cfu 1363 cfu1363 cfu 1352 cfu1352 cfu

PepsodentPepsodent 629 cfu629 cfu 520 cfu520 cfu 524.5 cfu524.5 cfu

Tom’s of Tom’s of MaineMaine

13541354 1283 cfu1283 cfu 1318.5 1318.5 cfucfu

ConclusionConclusion

My hypothesis was incorrect. The My hypothesis was incorrect. The Pepsodent cleaned your teeth the best, Pepsodent cleaned your teeth the best, not the Prevident 5000 Plus. The low was not the Prevident 5000 Plus. The low was 520 cfu for the Pepsodent. The high was 520 cfu for the Pepsodent. The high was 1363 cfu for the Prevident 5000 Plus. The 1363 cfu for the Prevident 5000 Plus. The difference between the two points was 843 difference between the two points was 843 cfu. Therefore I have learned that cfu. Therefore I have learned that Pepsodent cleans your teeth the best of Pepsodent cleans your teeth the best of these three brands. To take this these three brands. To take this experiment to the next step, you could experiment to the next step, you could explore the different types of bacteria. explore the different types of bacteria.