Your mouth is always trying to wear your teeth down, whether you recognize it or not. This's because the food you eat mix with your saliva and also the natural bacteria in your mouth to form dental plaque. This particular coating sticks to the teeth of yours and becomes harder, forming tartar which tears away at the enamel of your teeth. It's these resulting acids which cause holes as well as cavities. Cavities is a thing that affects everyone, but there are many risk factors which improve tooth decay.