A healthy mouth has 32 teeth. How many do you have? 32? That's great! But, remember that tomorrow, very suddenly, you can remain with only 31 or less. Teeth are a part of the body which are permanently in use. They do the difficult part for you and chew the food. You should thank them for that by taking care of them. Remember that the best way to keep your tooth healthy is to make prophylaxis. This includes a row of measures which you can practice depending on your time. But, it's important that you brush your tooth AT LEAST twice a day - after the breakfast and before you go to sleep.
Of course, having a toothbrush with you wherever you go is cool, but I doubt it's always possible. That's why after every meal take a bubble gum.
Hope it will help you