Mand. Premolars Flashcards
What is the shape of the crown outline of the mandibular 1st premolar from the buccal aspect?
Pentagonal (quintuple) shape.
Where is the buccal cusp tip positioned in the mandibular 1st premolar?
Centered over the root.
Which cusp ridge is shorter in the mandibular 1st premolar?
Mesial cusp ridge.
What are Thomas notches, and where are they typically found in the mandibular 1st premolar?
Notches on the cusp ridges; more common on the mesial cusp ridge.
What is the exception to the general rule about proximal contact points in mandibular 1st premolars?
Distal proximal contact is more occlusal than the mesial proximal contact.
Describe the lingual cusp of the mandibular 1st premolar.
Very small, pointed, and often aligned with the buccal triangular ridge.
What distinguishes the mesial and distal marginal ridges in the mandibular 1st premolar?
The mesial marginal ridge is more cervical than the distal marginal ridge.
What is a unique feature of the mesial aspect of the mandibular 1st premolar?
It has a mesiolingual groove separating the mesial marginal ridge from the lingual cusp.
What is the shape of the occlusal table of the mandibular 1st premolar?
Triangular, with the base towards the buccal aspect.
How does the mandibular 2nd premolar differ from the 1st premolar in terms of cusp tips?
The mandibular 2nd premolar has a more blunted buccal cusp.
How many cusps can the mandibular 2nd premolar have, and what are they called?
It can have 2 cusps (bicuspid) or 3 cusps (tricuspid).
What is the groove pattern of the mandibular 2nd premolar with 3 cusps?
Y-shaped groove pattern.
What is a key difference in the marginal ridge orientation between mandibular 1st and 2nd premolars?
In the 2nd premolar, the mesial marginal ridge is more occlusal, following the general rule.
Which cusp is larger in a tricuspid mandibular 2nd premolar?
The mesiolingual cusp.
What is the occlusal outline shape of a tricuspid mandibular 2nd premolar?
Square-shaped.
