The large back teeth. They are designed for crushing and grinding our food. Molars have multiple roots which support them. The Lower molars usually have two roots to support them and the upper molars usually have three roots to support them. The space between the roots of a tooth is called a furcation. We have three molars in each quadrant of our mouth. The first molar is closest to the front of the mouth and is located directly behind the pre-molar teeth. The second molar is located just behind or distal to the first molar and the third molar or wisdom tooth is located distal to the second molar. wisdom teeth are often removed due to lack a lack of space for them in the mouth.