The Coca-Cola Experiment

I have decided to check out the rumors what going around in the past few years, and will conduct the experiment myself.

I have put my son's milk tooth in a glass of cola and made a picture* of it every day for about 2 weeks, then once a few days.

Time by time I have washed it with toothpaste and toothbrush, then replaced the cola with fresh one.

For the experiment I used Coca Cola, because that is the most popular cola.

The result can be seen below.

* I made the photos in the mornings, next to the window, by natural light when it was possible. Because of this, the amount of the light and the tone are not always the same. So I was trying to correct the white balance with Photoshop, using the white copypaper as reference, what was serving as background. I have also adjusted the contrast/lightness on some photos, to make the smaller details more visible.

0. Day

The tooth was looking like this before the experiment. After rinsing and drying I made the first photo..

1. Day

The tooth was looking like this after the first day. After rinsing and drying I made the photo.
I guess, the brown layers are clearly visible.

2. Day

The tooth was looking like this after the second day. After rinsing and drying I made the photo.
The brown layer getting thicker.

.

3. day

The tooth was looking like this after the third day. After rinsing and drying I made the photo.
Around the sharp edges it is alredy black. The brown layer completly covered the whole tooth.


Then I washed it with the toothpaste and toothbrush.
The result of 2 minutes effort is can bee seen below.
The tooth is not as white as before the experiment, and the brown mark left strongly all around the sharp edges.
I have dried it, made the picture, then poured fresh cola on it..

4. Day

The tooth was looking like this after the fourth day. After rinsing and drying I made the photo.
The brown layer covered it much faster than before. On the bottom side is stronger than on the top. It is not sure, that the brown layer is belongs to the cola, or it is the material staying behind from dissolved the tooth.
Will see after the next toothbrush

5. Day

The tooth was looking like this after the fifth day. After rinsing and drying I made the photo.
The brown layer is getting thicker.
It looks like the cola has a different effect on the enamel and the root. On the enamel smoother and looser, on the root it is more sticky and hard

6. Day

The tooth was looking like this after the sixth day. After rinsing and drying I made the photo.
There is no much changes from the previous day. The brown layer looks a bit thicker.

7. Day

The tooth was looking like this after the seventh day. After rinsing and drying I made the photo.
The brown layer getting thicker especially on the edges on the root, and the enamel getting darker too.

8. Day

The tooth was looking like this after the eigth day. After rinsing and drying I made the photo.
At the first look there is no much different from the day before.


But fter brushing the tooth, we can see that the enamel getting thinner and covers less of the tooth's surface. From the areas what was not protected by the enamel, I could not remove the brown/black layer even with a lot of effort.
The edges are more jagged, and on the magnified part we can see that a "big" piece is missing. Perhaps it was weakened and broke off during the wash with the toothbrush.
The whole surface of the root now looks like a sponge, full of tiny holes.

9. Day

The tooth was looking like this after the ninth day. After rinsing and drying I made the photo.
The brown layer still thin, therefore we can see that the cola dissolved most tof the enamel.
At this point it is fair to say that the cola strongly erode the enamel and the other parts of the tooth, where it is not even.



Then I washed the tooth with toothpaste and tootbrush, to see better.
We can constate that the cola does not coloring the enamel much, but dissolve it.

10. Day

The tooth was looking like this after the tenth day. After rinsing and drying I made the photo.
Because I washet yesterday too, the brown layer still thin.


After washing, we can see that the enamel, where it still present, almost transparent.
On the root there are signs of acid-like damages.

11. Day

The tooth was looking like this after the eleventh day. After rinsing, drying then a wash with toothpaste and totthbrush I made the photo.
From now on I going tol wash the tooth because the thin brown layer only making harder to see the changes.
The root continuing to getting more jagged and the enamel almost completly disappeared, only a small piece left on the bottom left corner.

12. Day

The tooth was looking like this after the twelvth day. After rinsing, drying then a wash with toothpaste and totthbrush I made the photo.
From yesterday, seemingly no chanes, even the emanel stopped disappearing.

13. Day

The tooth was looking like this after the twelvth day. After rinsing, drying then a wash with toothpaste and totthbrush I made the photo.
Not much changes.
The enamel disappeared, and the brown material, what gives the color of the cola, soaked all the tooth.

16. Day

Because the changes were slowing down, I do not make photos every day.
The tooth was looking like this after the sixteenth day. After rinsing, drying then a wash with toothpaste and toothbrush, I made the photo.
The tooth getting darker cola colored. Around the edges even black, what can not remove with the toothbrush.

20. Day

The tooth was looking like this after the twentieth day. After rinsing, drying then a wash with toothpaste and toothbrush, I made the photo.
The changes are minimal. The jagged edges around the root were disappeared. I could not determine that they got dissolved by the cola or weared off by washing the tooth with the tootbrush.

26. Day


The tooth was looking like this after the twentisixth day. After rinsing, drying then a wash with toothpaste and toothbrush, I made the photo.
It is so dark, I need more light to make a photo and to the details to be visible. There is no great change. I have notised a piece missing from the chewing edge. It is better visible on the enlarged part.

31. Day

The tooth was looking like this after the thirtyfirst day. After rinsing, drying then a wash with toothpaste and toothbrush, I made the photo.
There is no serious change. Maybe the damage got deeper on the chewing edge, but it could be a light effect. The surface seems to be smoother now than around the second week, where the surface were a bit more rough.

35. Day

The tooth was looking like this after the thirtyfifth day. After rinsing, drying then a wash with toothpaste and toothbrush, I made the photo.
There is no change.

41. Day

The tooth was looking like this after the fortyfirst day. After rinsing, drying then a wash with toothpaste and toothbrush, I made the photo.

Again.... there is no change. - Apparently !!!!!


When we only concentrate on the VISUAL appearance of the tooth, obviously we could miss some other important changes. That happend to me. For weeks, I was looking for the visible signs of changes on the tooth.
During the regular washing the tooth, I have found, that the touch of the tooth become strangely soft.

I decided to conduct a "domestic" hardness test.

First, I inserted the tooth into a clothespin by the endpoins of its longest axe, to see what happends. It folded in the root immediatley. I have made a photo.



I can not tell exactly what is the pressure of the clothspin, but it is obvious, it is not really great. It is also obvious, that a healthy tooth is not supposed to bend or fold under the pressure of a clothspin.

Removed the tooth from the clothespin, and I made an other photo. It is clearly visible, that the root is folded onto the tooth, and the originally arched surface is now flat.

After making the photo, I unfolded the root by hand (with fingernails), and made an other photo. The root deformed, but did not brake off. The red arrow shows the dent what was caused by the tweezers I used to insert the tooth into the clothespin.

As a second part of the hardness test, I was trying to piecing the tooth with a sewing pin. With the pressure of my thumb, using medium power, I succeded piercing the tooth. The root still not brake off.


I could not say the numeric values of the piercing with the sawing pin, but but that is sure it is NOT possible to pierce a healthy tooth with it.

Here you can see the pin entering the tooth

And here the exit

So...
After 41 days, we can say, the tooth lost its main quality, its hardness. It is possible that it happend before, but I can't tell when.
It seems, that the material of the tooth is changed. The bone disappeared, and what left, is a much more soft material.
After all, I suppose, that the rumor on the internet is true, what says that the tooth soaked in Coca-Cola is disappearing, dissolving.
The object of the experiment can not called "tooth" any more. Only its shape remind us what it was before. Its most important properties and its material are not.
Exactly what is this material?

Maybe only those few people knows that, who garding the secrets of the ingrediens of the Coca Cola.

Day 52.
The experiment arrived to its last chapter.
This is the last time the tooth got washed. I was suprised that the signs of the hardness test are barely visible. The wrinkles on the root, caused by the fold, totally disappeared, and the place of the piercing also hard to find.

With a Stanley knife I cut the tooth in two. The knife run throuh with almost no resistance. I could not cut into equal pieces, despite all my efforts.

On the enlarged image as we can see, the middle of the larger piece is a little lighter. Perhaps this is a little bit of bone what left, caused the knife to slide to the side.

This is the enlarged image of the cross-section on the larger piece,
I found, this is a rarly nice cross-section of a tooth, even with its unusual color. Maybe a dentist can make more out of it.
On the bottom part we can see the surface of the cut is very smooth. That could indicate that the material is really soft.

The experiment now finished.
Everyone can decide for him/herself, what can be learned from this experiment.
I would encourage the visitors to repeat this experiment with Coca Cola, Pepsi, fruit juice, and other drinks, to see their effects on the teeth. It would bee intersting to compare the results.
Thank you for your time and interst, please live a comment at the end of the blog.

Huhan Provincial Museum

20 000 years ago
For reference, here is a tooth what was lying in the earth for 20 000 years.