Re: What is a good substance to form plaque?

   Plaque is basically a sticky mass of bacteria that accumulate on your 
teeth when you do not brush.  Their accumulation occurs through a very 
dynamic and complicated process that can really only occur in your mouth.  
Your idea of soaking the teeth in coke was pretty good, but to form plaque 
you need the correct temperature, saliva, and the correct bacteria.  My 
recommendation to you if you want to study mouth wash would be to get a 
group people who are willing to test the mouth washes for you.  To 
determine how much plaque thay have go to a local dentist, explain to him 
what you are doing and ask him if he will supply you with some "disclosing 
solution".  Disclosing solution is a red liquid that turns plaque red.  
What you can do is to use a Q-tip or cotton swab (preferreably a clean one 
for each person) to put disclosing solution on the teeth the people in 
your experiment and count how many teeth have red spots on them.  Then 
have each of these people use a particular mouth wash twice or three times 
a day for one or two weeks.  At the end of that time put disclosing 
solution on their teeth again and count how many teeth have red spots on 
them now. You can then compare and see if the amount of plaque decreased 
and which mouth wash cause the most reduction.  There is a lot more to 
testing mouth wash than this but I believe this will give you a good idea 
of what is out there and how well it works.  You might want to include 
some of the anti-tartar mouth washes in your study (i.e. the new 
listerine) which are supposed to be the most effective at calculus and 
plaque removal.  If you need to know more specifics about plaque formation 
let me know and I will get something to you.  Good luck.