Advise on my project idea please

[ilzepi]

Goodday,
I am in Gr 6 and still planning my science fair project. I would appreciate your advise on my ideas.

I did get some human teeth from a local dentist.
Half of the teeth I would like to test on different liquids - Coke, Coke Light, PowerAde, Apple Juice, Sparkling water, Tap water & Milk. The other half I would like to first put in Fluoride containing Oral Rinse and then in the liquids mentioned above, for the same period everyday.
I would weigh them daily, record the colour & record ph for teeth in the different liquids. Sugar content of each of the liquids is also important.
The two liquids with worst results (without fluoride treatment), I would like to test further, to see how I can prevent further damage of the teeth.

I want to grow bacteria on an agar medium, to also record results of bacteria in mouth.
I want to do this test 1 hour before drinking this liquid(without eating or drinking anything for at least 2hours), just after drinking it, repeat it after 1hour and then brush teeth (two minutes long with a specific toothpaste). I would like to see the growth of bacteria during the different phases an also record ph of mouth.
I plan to repeat the above again, brush and rinse with oral rinse and again brush, rinse and use floss. See if the results differ for the three different methods. I also thought about testing different toothpastes, but I am afraid it will get to complicated?
I would like to involve some of my friends in the project. Will it be possible to test each of above mentioned options on a different person? Or will it be better to use the same person for all the tests done?
I would like to do the same when I drink the two worst liquid with a straw. Would the results be different? Is a straw beneficial?
I would appreciate any advise or recommendations on my ideas? Thank you!

[DrSullivan]

Wow those are impressive ideas.

It sounds to me as if you are suggesting two different projects. I would either do the first one with the teeth, or the second one with your friends. If you choose to do the second one with your friends, I like the idea of doing it with multiple people. The bigger your sample size (meaning the more people you test), the more reliable are your results!

[ilzepi]

I started with research on my topic (1st topic) and there is another question that crossed my mind.
I can see that the saliva plays a major role in the mouth. Without it the sugar in the cooldrinks, will not be converted in acid.
So I will only test the acidity of the cooldrink and not the sugar?
Is there any way I can correct this problem?

[ilzepi]

Can I add artificial Saliva to my experimental groups?
But still bacteria is missing?
Maybe also add probiotics?
Regards

[MS15]

Hello!
These are great questions while planning such an experiment! To clarify some of the points you raised:

1. Enzymes in our saliva (primarily, amylase) help to break down carbohydrates and complex sugars in our food to simple sugars (like glucose) which can then be more easily digested and absorbed.
2. Bacterial residents in our mouth utilize nutrients from our food for their growth and when they metabolize sugars, they produce acids like lactic acid by a process called fermentation. These acids cause damage to teeth enamel.

Now if you are just interested in the acidity of the various drinks you are testing, checking the pH should be enough. If you also want to test sugar content of the samples, then yes, you can add artificial saliva or purified amylase to quicken the process of breakdown of complex sugars like sucrose.

I would stay away from adding probiotics because a) different people have different mouth flora so it's an added variable that complicates the basic question of the effects of your test samples and b) if you are thinking of food-based or even over the counter probiotics, they mostly contain gut-resident bacteria which are different from those in our mouth.

Good luck with your experiment and feel free to write back if there are more questions!
MS

[ilzepi]

Hi!
Thank you for your great advise! It is difficult to get Amylase Powder in Namibia. But it seems as if one of the breweries will be able to help me with a small amount.
I have drawn a table of all the cooldrinks applicable - amount of sugar, ph, what acids it contains and other ingredients. I am also planning to test the ph before I start my project, to compare it.
I have another concern..
In my project I want to see what influence the different cooldrinks have on our teeth. To reduce my variables, I want to create an environment similar to the environment in our mouths.
Amylase will convert the sugar in, for example Coke to smaller sugar molecules. But in the mouth, the bacteria convert this sugar again to acid. The acid is what is causing the damage to out teeth.
Is the only way to do this, maybe by using real saliva? But I am a little bit afraid of using actual saliva, because of safety procedures?
If that will be the best altenative, I will have to be very strict while doing the project. Maybe let every person fill in a questionare to qualify? No sicknesses at all.
I am not sure what to do? Can you please advise me.

[MS15]

You're welcome and I'm happy to learn that it was useful! First, congratulations on finding an alternative source of Amylase for your experiment and good thinking about finding this alternative. Your plan of drawing up a table to compare and contrast the different parameters you are studying sounds like a good way to proceed.

Now regarding your question about using saliva, you are totally right about your concerns. Working with any kind of body fluids from humans or animals requires specialized safety procedures and facilities which I do not think would be accessible to someone in middle school. Now going back to DrSullivan's comment on your first post, I think adding in an additional variable of different people is very complicated and could be a separate project question altogether from the one you are currently doing with the teeth that you obtained.

Here's an idea: If you absolutely want to use saliva in your experiment to help the production of acid, why not just use your own? That way it will be a constant variable across all the conditions/drinks you test (your microflora composition is unique and the same will go into all samples). Plus you need not fear any risk of infection at all. However, please make sure that no one else comes into contact with your saliva or samples.

Please let me know if you have additional questions! Good luck!

[ilzepi]

Good day,
I have finished the first phase of my project for this year. It is titled Demineralization of teeth.
Through my project I proved what drink is worse for your teeth and the scientifically reasons why (Ph, sugar content, acid).
For the second phase of my project I would like to prove that Remineralization of teeth is possible.
I started with some research, but it seems more difficult than I thought...
Can you please advise me on this project?
I am thinking of using the same procedure that I used to prove demineralization - leave each teeth in a specific drink for 6hours - to demineralize. Then leave it in a "remineralization - solution" to see if I can remineralize the teeth again. Will do this by weighing the different teeth each time.
There is different minerals that helps with remineralization:
Fluoride - Topical Flouride application or fluoride oral rinse?
Calcium - Not sure how to prove this? Will have to look for a soluble Calcium powder maybe?
Vit D - Calciferol drops - coat the teeth with the oil?
Phosfor - Also difficult to prove this, because of the availability of this minerals?
Maybe try with each mineral separately and then a combination of all the minerals together? The right ratio will be important. Ph will also be important for Remineralization to occur (alkaline).
Xylitol can also be used?
I can also use anti-bacterial ingredients - maybe some with is found in oral rinse?
There is so many options available - also bicarbonate of soda, activated charcoal, Kaseien (milk proteien)?
Please help me? Not sure where to start and how to formulate this study?
Do you think it will be possible to formulate an oral rinse with the end results? A Remineralization rinse?
I appreciate you time and help!

[MS15]

Congratulations on completing phase I successfully!
The second phase is also very interesting and it sure sounds like there's a whole lot of things you could try. You could pick one or two options that are relatively easy to perform but do keep in mind that the changes in weight will be really tiny so you will need a very sophisticated and sensitive balance for your measurements.

This is outside of my expertise, so I am requesting other experts to weigh in if possible.