It's also possible that you have the correct application on your PC, but .afp files aren't yet associated with it. In this case, when you try to open a .afp file, you can tell Windows which application is the correct one for that file. From then on, opening a .afp file will open the correct application.
Dentin is found underneath the enamel surface of the tooth and underneath the cementum that forms along a tooth's roots. Made of living cellular material and tissue, dentin is what makes up the majority of a tooth's structure. Dentin is a bone-like substance that contains microscopic tubules. Unlike enamel, exposed dentin is highly susceptible to the bacteria that cause dental cavities and can cause tooth sensitivity. Cementum.
The part of the tooth that you can see is called the crown. The outer part of it is covered with a hard white material called enamel which protects the tooth. It is often hard and shiny and acts as a tooth's bodyguard. It protects the inside parts of the tooth. Below it is dentin, a yellow bonelike material that is softer than the outer part.