In the human dentition, premolars belong to the molars. In the permanent dentition, there are two premolars per quadrant, situated between the canine teeth and the molars.
Originally, there were 4 premolars in each half of the jaw, but over time, however, these have been reduced to 2. Rodents no longer grow premolars at all. In the human dentition, premolars usually have two cusps and two root canals.