How does the the mandibular second premolar differ from the mandibular first premolar?
- Its crown is generally larger.
- The lingual cusp is better developed although it is not quire as large as the buccal cusp.
How does the mandibular second premolar appear from the occlusal aspect?
- From the occlusal aspect its outline appears round or square, the mesial and distal profiles being straight and parallel.
- The mesiodistal occlusal fissure between the cusps is well defined.
- However, like the first premolar, the fissure ends in mesial and distal fossae, the distal fossa being generally larger than the mesial.
- Unlike the first premolar, a transverse ridge does not usually join the apices of the cusps.
What are the cusps like on the mandibular second premolar?
- The lingual cusp is usually subdivided into mesiolingual and distolingual cusps, the mesiolingual cusp being wider and higher than the distolingual.
- The groove separating the mesiolingual and distolingual cusps lies opposite the tip of the buccal cusp.
How does the mandibular second premolar appear from the buccal aspect?
- From the buccal aspect, the crown of the second premolar is symmetrical.
- From this view the buccal cusp generally appears shorter and more rounded than that of the mandibular first premolar.
How does the mandibular second premolar appear from the lingual aspect?
Lingually, little if any of the occlusal surface and buccal profile is visible.
How does the mandibular second premolar appear from the mesial and distal aspects?
- From the mesial and distal aspects the occlusal surface appears horizontal to the long axis of the tooth, unlike the mandibular first premolar.
- The crown is wider buccolingually than that of the first premolar and the buccal cusp does not incline as far over the root.
- The mesial marginal ridge is higher than the distal marginal ridge.
What is the cervical margin and the root like for the mandibular second premolar?
- The cervical margin follows an almost level course around the tooth.
- The root is single, conical, and nearlly round in cross section.