Tooth types, illustration. Colour-coded illustration of the different types of teeth found in the upper and lower jaw. Incisors (yellow) are found at the front of the mouth and are used for cutting food. Canines (red) are the sharpest teeth in the mouth, and are used to tear food apart. Unlike incisors and canines, premolars (green) and molars (blue) have broader, flatter biting surfaces. These are used for grinding and crushing food. The wisdom teeth (purple) are a type of molar sometimes found at the back of the mouth. Often these do not emerge from underneath the gum, but when they do then they can cause severe discomfort for the patient.