Final answer:
The edge of a tooth is defined by its cusp. The canine or cuspid has a pointed cusp for tearing food, while premolars and molars have different shapes for mashing and crushing food, respectively.
Step-by-step explanation:
The characteristic shape made by the edge of a tooth is known as the cusp. Teeth come in various shapes and sizes, each adapted to a specific function. The crown is the portion of the tooth visible superior to the gum line. The cuspid, or canine, is the pointed tooth used for tearing and shredding food. It is one of the four pointed teeth that flank the incisors and have a pointed edge to effectively tear up food. Posterior to the cuspids are the premolars, which have a flatter shape with two rounded cusps useful for mashing foods. The most posterior teeth, the molars, have several pointed cusps and are involved in crushing food for swallowing.