Tooth #12 – Upper left first premolar
4th tooth back from the middle, upper left.
- International
- 24
- Palmer
- 4
- Type
- Premolar
- Roots
- 2
- Canals
- usually 2
- Comes in
- 10–11 years
The first of the two smaller back teeth (premolars) on the upper left, just behind the canine.
- In front: #11 upper left canine
- Behind: #13 upper left second premolar
- Same tooth on the other side: #5 upper right first premolar
- Bites against: #21 lower left first premolar
It replaces the upper left baby first molar (I), which falls out at 9–11 years.
Usually two roots (1–3) and usually two canals (1–3).
Upper first premolars: roots, canals and the studies behind the counts →
This tooth is #12 in the US and 24 in the international (FDI) system, where the 2 means the upper left quarter and the 4 is its place counting from the front.
In the international system, 12 is the upper right lateral incisor (#7).
And in the US, #24 is the lower left central incisor.
American Dental Association 2024; Harris 2005; American Dental Association 2012. Full titles are on the About page.