The Effect of Various Cleansers on the Removal of Tooth Stains
Researched by Tayler T.


The purpose of this experiment was to determine the effect of various cleansers on the removal of tooth stains. 

I became interested in this idea because I have been fascinated with teeth ever since I was very young. I knew that people need to have clean, healthy teeth for good digestion and appearance. 

To improve the health and appearance of their teeth, consumers could use the information gained from this experiment to make wise purchases. 


My hypothesis was that all toothpastes with fluoride would work equally well. 

I based my hypothesis on Dr. Bennett Packard who said, "I recommend any toothpaste with fluoride to my patients. I definitely do not recommend natural toothpastes."

The constants in this study were:
  • The amount of toothpaste used to brush the teeth
  • The amount of time the teeth were brushed
  • The amount of time the teeth were soaked in the stain
  • The type of manual toothbrush used to brush the teeth
  • The amount of substances in the container
  • The type of substances in the container
  • The amount of stirs the teeth were stirred 

The manipulated variable was the type of toothpaste I used to remove the stains. 

The responding variable was the amount of stain removed. 

To measure the responding variable I used a hunter reflectance spectrometer to determine whiteness. 

20 Teeth
 Oral-B Toothbrushes
495mL  Stain
1 Bowl
Rubber gloves
1 Pair of tongs
1 Tube of Colgate toothpaste
Tube of Mentadent toothpaste
Tube of Crest toothpaste
1 Tube of Aqua Fresh toothpaste
Tube of Tom's of Maine toothpaste
5 Paper towels
Pair of eye goggles
1 Hunter Reflectance Spectrophotometer


1. Put on rubber gloves and eye goggles.
2. Place 4 different paper towels on a counter to set the teeth down on when they are done.
3. Give each of the toothpastes a group number of 1-5
4. Give each tooth a code name like group 1 tooth 1. 
5. Label 5 different paper towels with the group name that you gave them. 
6. Mix 60 mL of mustard, 60 mL of ketchup, 60 mL of oil, 90 mL of red wine, 60 mL of grape juice, 90mL of black coffee, and 75 mL of Prego spaghetti sauce in a blender until it is smooth. 
7. Stain all the teeth by soaking them for 10 hours in a large bowl. 
8. Stir the teeth every 30 minutes. 
9. After 10 hours remove the teeth with tongs. 
10. Get one toothbrush ready by putting about 1 gram of Colgate             toothpaste on the Oral-B toothbrush. 
11. Brush one tooth up and down for 1 minute.  Repeat steps 8 and 9 with the other 3 teeth in this group. 
12. When the teeth are done being brushed put all 4 of them on the correct paper towel. 
13. Brush 4 more teeth with Crest toothpaste (refer to steps 8-11 for directions on how to brush them)
14. Brush 4 other teeth with Aqua Fresh toothpaste. (Refer to steps 8-11 for directions on how to brush them.)
15. Brush 4 more teeth with Mentadent toothpaste. (Refer to steps 8-11 for directions on how to brush tem.)
16. Brush the other 4 teeth with Tomís of Maine natural toothpaste (refer to steps 8-11 for directions on how to brush them.)
17. Label 20 ziploc baggies with the tooth code. 
18. Put each tooth in the correct baggies. 
19. Place each tooth in the hunter reflectance spectrometer test vial. 
20. Record lightness results on data sheet 
21. Arrange all the teeth data into groups
22. Compare the teeth numbers in one group to the others.


The original purpose of this experiment was to determine the effect of various cleansers on tooth stains.

The results of the experiment were that Mentadent came in first, Aqua Fresh came in second, Tomís of Maine came in third, Crest came in fourth, and Colgate came in fifth.

View the table and graph.


My hypothesis was that all toothpastes with fluoride would work equally well. 

The results indicate that this hypothesis should be rejected.

Because of the results of this experiment, I wonder if brushing with an electric toothbrush would give similar results to a manual toothbrush, like I used in this study.  I also wonder if using stains separately instead of in a mixture would show which toothpaste is better for a specific stain.

If I were to conduct this project again I would have conducted more trials, by using more teeth. I would also test the teeth while they were stained so that I would be comparing would be of the same sort. 

Research Report

A healthy mouth is very important. Thatís why brushing your teeth is a very critical activity. When you donít brush your teeth enough, more and more plaque clings onto your teeth causing cavities and tooth decay. This affects appearance and digestion.

Caring for Your teeth
Brushing your teeth is not overly time consuming. It takes two minutes three times a day. If you donít want stained teeth then you need to take ten minutes out of your day to brush and floss youíre teeth. When a child is two or three they should start learning and be shown how to care for their teeth. At the ages of five or six a child should be able to brush their teeth without any assistance. If there is a child in the house, an adult should schedule dental appointments every year. The dentist or orthodontist will then check for tooth decay or cavities.

What Are cavities?
Bacteria are constantly growing in your mouth. Some bacteria stick to hard surfaces like enamel. Enamel is the hard material that covers your teeth. When bacteria are on your teeth for a long period of time acids are produced that can turn into tooth decay. Then the tooth decay turns into a cavity. Cavities are holes in the enamel that expose the cemetum.

Parts of a Tooth
Enamel is the hard white material that covers your teeth. Enamel is the hardest part of your body. Dentin is also another important tooth material, which is inside the enamel in your teeth. Dentin is a yellow bonelike structure. The dentin also has nerves inside of it. When you have a cavity it leaves the dentin exposed which causes the pain. Pulp is at the very center of your tooth. Pulp contains important blood vessels and nerves. The pulp protects the nerves so they can send messages to your brain. Cemetum is the material that covers the root of your tooth. It also attaches the tooth to the jaw.

Brushing your teeth is not enough. Thatís why you need to floss the gum line and deep down in the spaces between teeth where toothbrushes cannot reach but floss can. In order to floss you must first get a piece of floss. Then, you must pull the floss between every tooth on your upper and lower jaw. It is important to floss because between the teeth is where diseases start.

How to Brush Your Teeth
Brushing your teeth is very simple. First, you put about one gram of toothpaste on your toothbrush. Next, you wet your toothpaste lightly. Then, put the toothbrush in your mouth and move it up and down. You always want to move your toothbrush up and down instead of right to left because it gets more plaque off of your teeth.

There are many different kinds of toothbrushes. "Electric toothbrushes are the best!" says dentist Bennett Packard. " They keep it fun so kids will want to brush their teeth. Scientific research shows that soft bristles are the best. There are many different brands of toothbrushes but they are all about the same even if they say that their type of toothbrush is better. 

There is also a wide variety of toothpastes. There is Crest, Colgate, Aqua Fresh, Mentadent, Tooth White, and many more. There are two general kinds of toothpastes, toothpaste with fluoride and toothpaste without fluoride. Dentists have found that toothpaste with fluoride works better then a toothpaste without fluoride and is natural. Dr. Packard said that most dentists do not recommend any kind of specific toothpaste any more, they just recommend that the toothpaste has fluoride in it. 

What things stain your teeth the most
There are many foods and beverages that are harmless to your teeth, however there some things that you might want to watch out for. The substances that stain your teeth the most are smoking, coffee, red wine, sugar and candy. Smoking harms your teeth due to the tobacco that is in it. Coffee stains your teeth because of the citric acid, caffeine, and sugar. Red wine is harmful to your teeth because of the color and sugar. Candy stains your teeth because of the sugar. Sugar is harmful because it decays your teeth. If you were to down a cup of sugar and swallow it within a short period time that would be better then if you were to suck on a small piece of candy the size of a tootsie roll. 

Why Brush Your Teeth
Brushing your teeth after you eat doesnít only get food particles out that you can see, but it gets food particles out that you cannot see, plus it gets plaque off of your teeth. Using a fluoride toothpaste along with an electric toothbrush is probably the best combination there is. 

Mouth Rinses and Mouthwashes 
Mouth rinses and washes are good if you use them in the right way. If you use them as directed and brush and floss your teeth then mouthwashes and mouth rinses can help prevent tooth decay and bad breath. 

Hunter Reflectance Spectrophotometer(Colorimeter)
A Hunter reflectance Spectrophometer is also known as a colorimeter. This machine measures color. A colorimeter uses A, L and B scales to measure color. The letters A and B are not the easiest thing to explain. The scale A measures green vs.  red. The scale B measures yellow vs. blue. A colorimeter has a hole as the top in which a light shines through. This light measures the lightness and/or darkness of the object you are testing. Before you can find the value of the object you are testing you must first standardize sthe colorimeter. Once you have standardized it, you place your object over the light and then press the icon that says "scan". L=92.89, A=0.93,and B=0.43 are the values of the tile. You will not find anything whiter than this white tile. 

Brushing your teeth is very important. If you donít want stained teeth then you need to take ten minutes out of your day to brush and floss your teeth. A cavity is a hole in the enamel that exposes the cemetum. Teeth are made out of three different materials. You need to floss your teeth to get the food particles out from between your teeth. All you do to brush your teeth is put one gram of toothpaste on a toothbrush and then move it up and down in your mouth. Some of the things that stain your teeth the most is smoking coffee, red wine, sugar, and candy. You need to brush your teeth so you can get out all of the food particles. 


Charnan, Simon. "Dental Hygienists" Minnesota: Capestone Press, 1998. Pp.5-47

"Dentistry" The World Book Encyclopedia, 1998

"Health Care In America" U.S.A.: Green haven Press, 1994.pp. 8-12

Lund, Bill. "A Career In Health" Minnesota: Capstone Press, 1996.pp.24-27

OíNeil, Karen. "Health and Medicine" U.S.A.: Congress, 1986.pp.1-8

Siegel, Dorothy" Dental Health" New York: Chelsea House Publishers

Wynne, Patricia, J. "Teeth" The World Book Encyclopedia, 1999s

I would like to thank the following people:
  • Dr. Darrel Tew for taking the time to sterilize and save the teeth that he had pulled out so I could use them for my experiment. 
  • Mr. Newkirk for giving me advice, correcting my papers, and helping me get through the hard times. 
  • Mrs. Helms for always being there when I had a question or a problem. 
  • My parents for transporting me and buying materials that were needed for my experiment. 
  • My sister for transporting me and giving me great advice throughout my project. 
  • Dr. James Taylor for helping me get a hold of different dentists who could help me.
  • Tom Eisele for helping me put the teeth through the hunter reflectance spectrometer.

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