A sealant is like a cavity in that we put a composite resin in the tooth. The main differences are that sealants start out more liquid and they are done for preventative reasons rather than for repair. Teeth have grooves in the chewings surfaces. Many times they are much smaller at the bottom than the size of a tooth brush bristle (see the top left portion of the image below). So even if you clean your teeth well, you will not be able to clean the bottom of those skinny grooves. This leaves bacteria and sugars down there to turn into a cavity. To prevent this we place sealants.
In the image above, you can see the four steps of the sealant process. The first (top left) shows how a tooth brush bristle will not be able to get down and clean out the lower portion of this molars central fissure. We clean these out with a special liquid tooth surface cleaner. Once cleaned and rinsed we place the sealant material. Because it is so liquid it flows down into the bottom of the grooves. We shine a light on the liquid filling so that it turns hard. In the end you are left with a normal shaped tooth, but no deep grooves left to turn into cavities. At Snoqualmie Falls Dental we guarantee the sealants will stay in for at least two years or we will replace them for free!