Science Buddies: "Ask an Expert"

I've done a lot of research about bad breath. I'm trying to see how sodium fluoride and ingredients in mouthwash fix bad breath.

Bacteria live in anaerobic, acidic environments. They create smelly sulfur compounds. Bacteria eat sugar so sugary gum/mints will not help bad breath in the long run. Drying agents will speed up the growth of bacteria. Cysteine and Methionine are amino acids that can turn into hydrogen sulfide and methyl mercaptan, which are both stinky gases.
That's the gist of what I've read. But it's mainly biology.

I can't find anything about how, in terms of the molecular structures.
Or maybe it isn't even that difficult.
Changing the pH from acidic to neutral/more basic destroys the environment that bacteria live in. I think changing the pH is how sodium fluoride works but I don't know how exactly.
Also, if you introduce oxygen to under the surface of the tongue, it kills the bacteria. Does toothpaste or mouthwash possibly oxidize the mouth?

It's really hard finding the chemistry of processes. I would appreciate your help very much. Thank you in advance.

Hi,

Here is a paper summary reporting a study of Colgate Total vs. fluoride toothpates on reduction of oral bacteria and bad breath:

http://www.ncbi.nlm.nih.gov/pubmed/14692207

Sodium fluoride acts by hardening tooth enamel, but is not active against odor causing bacteria as far as I know. Triclosan is the antibacterial agent in Total toothpaste.

Here is a site talking about halitosis treatments that cites some clinical studies:

http://www.smartmouth.com/SmartMouth_BBB_Report.pdf

http://www.ncbi.nlm.nih.gov/pubmed/11577950

http://www.halimeter.com/images/ratcliff1.pdf

Here are some research articles:
http://www.cda.org/page/Library/cda_mem ... 07/lee.pdf

http://jdr.sagepub.com/cgi/reprint/79/10/1773

http://www.ncbi.nlm.nih.gov/pubmed/9086681

http://www.bioline.org.br/request?os08032

http://jmm.sgmjournals.org/cgi/reprint/54/9/889

http://www.fluorideinformation.com/imag ... load21.pdf

Here is an article on the reaction of sodium fluoride and tooth enamel:

http://www.sciencedirect.com/science?_o ... b5cdc0c985

http://www.jbc.org/content/134/2/543.full.pdf

http://informahealthcare.com/doi/abs/10 ... 3599428562

http://jdr.sagepub.com/cgi/reprint/41/2/413

So my conclusion is sodium fluoride interacts with dental enamel (hydroxyapetite) mainly by rematerializing teeth, preventing dental caries from developing. It does not seem to be directly influencing halitosis (bad breath) in the vast majority of instances. Zinc salts are more interesting in their effect on some forms of Halitosis. This seems to be an understudied area, as several of these references point out.

I hope this answers some of your questions. Good luck on the project!

Best regards,

Barrett L. Tomlinson

I was going to try to help, but it seems like Barrett has given you comprehensive information on this topic. Good job dude.
Sumit Mitra

Thank you Barrett for your reply! And thank you Sumit for having the intentions to help ^-^

I'm asking my group mates to change the concept from bad breath to bacteria. I realized that the way we analyzed our data has to do with bacteria colonies and nothing with bad breath. We only chose the term "bad breath" because the experiment included raw garlic.
You basically confirmed that I was on the wrong track the entire time. Haha. But thank goodness I didn't waste anymore time on sodium fluoride. However, I do think Triclosan can give me more information.
Thank you very much for all the links. It will help me with mouthwash as well~

And if you have any additional information about how Triclosan, the active (or perhaps inactive) ingredients in Listerine mouthwash, and Listerine Breath Strips kill bacteria in the mouth, please share! Well in the case of the breath strips, it's how they don't kill bacteria.
I know how everything works and which of the three solutions work, but I'm having trouble with finding the chemistry of it.