The premolar teeth or bicuspids are transitional teeth located between the canine and molar teeth. In humans, there are two premolars per quadrant and are identified as first and second premolars. They have at least two cusps. There is always one large buccal cusp, especially so in the mandibular first premolar. The lower second premolar may, at times present with two lingual cusps.
Premolar teeth by definition are permanent teeth distal to the canines preceded by deciduous molars. In primitive mammals there are four premolars per quadrant. The most mesial two have been lost in New World monkeys, apes, and humans. Paleontologists refer to human premolars as Pm3 and Pm4 .