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Maxillary left first premolar
A two-cusped (buccal and palatal) premolar. It usually has two roots, which distinguishes it from most other premolars.
- FDI
- 24
- Universal
- 12
- Palmer
- UL4
- Roots
- Usually two (buccal and palatal)
- Root canals
- Usually two
- Eruption
- About 10–11 years
Form and anatomy
The crown has a buccal cusp and a slightly shorter palatal cusp, and seen from the occlusal side its outline is hexagonal. Unusually, the buccal cusp tip sits a little distal to centre, because its mesial cusp ridge is the longer one. A developmental depression on the mesial surface of the crown continues onto the root, and a groove often crosses the mesial marginal ridge; both make this surface harder to restore and clean. The central groove is long and runs mesiodistally between the two cusps. Most teeth have two roots, one buccal and one palatal, which may separate in the middle or apical third; single-rooted and occasional three-rooted forms also occur. Each root usually has its own canal, and the thin, curved roots call for care during extraction and root canal treatment.
Function
Transitions from tearing to grinding; holds and crushes food.
Clinical relevance
Frequently extracted for orthodontic space. Two canals are typical, so both must be located in endodontic treatment.
Neighbouring teeth
- Mesial neighbour
- Maxillary left canine
- Distal neighbour
- Maxillary left second premolar
- Same tooth, other side
- Maxillary right first premolar
- Opposing tooth
- Mandibular left first premolar
This text is a draft and has not yet been reviewed by a dental professional. Educational reference only, not for diagnosis or treatment.