The term premolar is used to denote any tooth in the permanent dentition of mammals that replaces a primary molar.
There are 8 premolars – 4 in the maxillary arch and 4 in the mandibular arch. They can be identified by the International Numbering System using the formula of Viohla as teeth 14, 15, 24, 25 for maxillary premolars and 34, 35, 44, 45 for mandibular premolars.
Functions: The premolars function with the molars in the mastication of food and in maintaining the vertical dimension of the face. They assist the canines in shearing and cutting food morsels. All premolars support the corners of the mouth and cheeks from sagging, which is more visible in older people.
Fillings in premolars should be aesthetic, especially on mesio-occlusal surfaces of upper first premolars in patients with a wide smile and a high lip line.