This type of study is used when there is a large population of people or animals who have developed a certain type of disease. The people who study this are called Epidemiologists.
An Epidemiologist determines what can be done to protect people so that they will not get the disease. They also study the factors of what is associated with the disease itself. The main types of study are;
Well, I'm no expert but U can try baking soda and hydrogen peroxide... mix them up and then swish in your mouth. but dont do it 2 often, because those are both very acidic! Hope I helped
