maxillary PM

How many premolars are there in the permanent dentition?

8

What are the numbers of the maxillary premolars?

Upper right (4,5) Upper left (12,13)

What are the numbers of the mandibular premolars>

Lower left (20,21) Lower right (28,29)

what are the functions of the PM?

• Function with molars to chew food

• Maintain vertical dimension of face

• 1^st PM assist canines in shearing/cutting food

  • All PM support corners of mouth and cheeks to keep from sagging

Pm develop from ___ lobes

4

Facial develop from ___ lobes: usually seen by 3 prominences, a central buccal ridge and mesial and distal portion separated by ___ shallow, vertical depressions

3; 2

Lingual surfaces of most PM develop from __ lingual lobe

1

Forms lingual cusp, not a_____

1; cingulum

crowns taper narrower towards…..

cervical and the lingual

mesial and distal surfaces are _____ around ____ area

convex; contact

Cervical line curvature on proximal curve toward ____ surface (slightly greater on mesial than distal when viewed from proximal)

occlusal

On facial and lingual views curves….

toward root apex

how many roots do PM have?

1 root; convex on facial and lingual, taper apically

maxillary 1st premolars have how many roots?

2 lingual root is less bulky than buccal root

when apical ___ bends, most often bent ____

1/3; distally

Pentagon-shaped crowns

Maxillary PM- buccal view

1st PM, mesial and distal converge more noticeably from the contact areas to cervical line…

cervical portion appears narrower

On the 2nd premolars the ____ cusp ridges shorter than ____

mesial; distal