Flashcards in Maxillary first premolars Deck (19):
Buccolingually or mesodistally, which is wider? What is the shape of the occlusal outline?
Wider buccolingually and has an oval shape occlusal outline
Typically, how many cusps on this tooth? What are they?
2 cusps; buccal and lingual
What are the depressions on the buccal surface called that divide the tooth into lobes? How many lobes are there? And which lobes has a specific characteristic, what is it?
There are 2 developmental depressions; distobuccal and mesiobuccal that divide the buccal surface into 3 lobes. The central lobe has a buccal ridge that extends from the cusp apex to the root
The mesiobuccal line angle is rounded. True or False?
False, the mesiobuccal line angle is sharp. The distobuccal line angle is rounded.
Which cusp is taller?
What structure connects the buccal and lingual cusps?
Mesial and distal marginal ridges
What crosses over the mesial marginal ridge and extends on to the mesial surface?
Mesial marginal groove
Describe the mesial concavity or mesial developmental depression
On the mesial surface is a concavity that extends from the HOC to the root and its a good way to distinguish first from second maxillary premolars.
Mesial and Distal HOC on all posterior teeth
Between middle and occlusal third (distal HOC closer to cervical line than mesial)
Buccal HOC on this tooth
Between middle and occlusal third (same as maxillary second premolars)
lingual HOC on this tooth
in the middle third (same as maxillary second premolars)
Typically, how many roots?
1 or 2 roots can be presents (buccal and lingual roots)
Describe the displacement of the lingual cusp.
The lingual cusp is displaced slightly towards the mesial
What structures mark the boundaries of the occlusal table?
Distobuccal cusp ridge, distal marginal ridge, distolingual cusp ridge, mesiolingual cusp ridge, mesial marginal ridge and mesiobuccal cusp ridge.
The mesial and distal pits are connect by what?
What strcutures emanate from the pits?
The mesiobuccal and mesiolingual grooves from the mesial pit and distobuccal and distolingual grooves from the distal pit
The buccal cusp ridge (random fact)
It is straight and not parallel to the central groove
What are the ridges that are present on the occlusal table that give a triangular appearance in cross section?
Buccal and lingual triangular ridges