Dental Anatomy: Permanent maxillary premolars

Permanent premolars:
?The maxillary premolars are four in number: two in the right and two in the left. They are posterior to the canines and anterior to the molars.
?The maxillary molars have shorter crowns and shorter roots than those of the maxillary canines.
?The maxillary 1st premolar is larger than the maxillary 2nd premolar.
?Premolars are named so, because they are anterior to the molars in permanent dentitions.
?They succeed the deciduous molars (there are no premolars in deciduous dentitions.
?They are also called “bicuspid-having two cusps”. This term is not widely used, because the mandibular 1st premolar has one functional cusp.
The premolars are intermediate between molars and canines according to the following:
?Form: the labial aspect of the canine and the buccal aspect of premolars are similar.
?Function: the canine is used to tear food while the premolars and molars are used to grind it.
?Position: the premolars are in the centre of the dental arch.
Some characteristic features to all posterior teeth:
?1-Relatively, greater facio-lingual measurement in comparison with the mesio-distal measurement.
?2-broader contact area.
?3-contact areas nearly at the same level.
?4-less curvature of the cervical line mesially and distally.
?5-shorter crown cervico-occlusally when compared with anterior teeth.