Anatomy of Teeth

Each tooth may be said to consist of four main parts:

Enamel - this is the outermost, visible layer of the tooth
Dentin - this lies inner to the enamel and is the main part of the tooth
Pulp - this part of the tooth contains the nerves, blood vessels and tissues
Root - as the name suggests, this part anchors the tooth to the jaw.

Development of teeth:

Teeth formation starts in the fetus at the six weeks stage. This is the stage when the basic parts of the tooth form. This is followed by the formation of development of the hard tissues, after three to four months in the fetal stage. The next stages of formation occur after the baby is born, when the actual protrusion of the teeth from the gum occurs. The last stage occurs with shedding of the baby teeth. This usually starts when the child is around six years old. This is followed by starting of emergence of permanent teeth. The last baby teeth are usually lost when one is around twelve years old. There are a total of thirty two permanent teeth, the last of which to occur is usually a molar, and are referred to "the wisdom tooth".