Expert: Walter Hintz - 10/11/2006

Question
hi...

i am doing a science project for school. here is a copy of the assignment:

Manufacturers of different brands of mouthwashes often claim that their brand is better, kills more bacteria, and prevents bad breath for a longer time.  

Different brands of mouthwashes also have different price ranges. Are you getting a better and more effective product when you buy a more expensive brand?

Like any other consumer product, mouthwash can be tested for effectiveness in removing bacteria and killing bacteria.

In this project you will perform experiments to compare different mouthwashes for their ability to kill germs.

it would be appreciated if you could give me some info on how to perform this experiment...bacterial growth...ect. cause i really have no clue where to begin. some websites will do i guess. thanks for your help!!!

Answer
There are a number of ways to do this Jay.  You will need bacteria media plates.  Here is what I would suggest. Decide which mouthwashes you are going to test. Cut som small circles of filter paper and soak them in the different mouthwashes.  Swap your mouth with  a sterile swap and innoculate the media plates (petri dishes  Put the circles of mouthwash in the middle of the petri dish. Each brand of mouthwash on a separate plate.  Be sure you have a control palte with no mouthwash.