Card Set Information
General Characteristics of All Posterior Teeth
Two or more cusps
Occlusal table with ridges and grooves
Marginal ridges perpendicular to long axis of the tooth
Facial height of contour
: cervical third
Lingual height of contour
: middle third
General Premolar Features
One buccal cusp
One (or two) lingual cusps
Transitional between canines and molars in function
Why is the term bicuspid inaccurate?
Premolar Occlusal Table
Each cusp has 4 cusp ridges.
One cusp ridge = triangular ridge.
Two triangular ridges = transverse ridge.
Marginal ridges border the occlusal table.
Buccal and lingual cusps of nearly equal size
Occlusal surface wider buccolingually than mesiodistally
1st larger than 2nd
Maxillary 1st Premolar
: buccal and lingual
Angular occlusal table
Mesial marginal developmental groove
Mesial crown concavity
Buccal cusp slightly longer than lingual
Lingual cusp offset to mesial when viewed from lingual aspect
Maxillary 2nd Premolar
Rounded occlusal table
Buccal and lingual cusps nearly equal
Buccal and lingual cusps in line
No mesial groove and concavity
Maxillary 2nd Premolar:
how to tell mesial from distal
List features that distinguish maxillary 1st and 2nd premolars.
Large buccal cusp
2nd larger than 1st
Very small lingual cusp(s)
Buccolingual = mesiodistal crown dimension
Lingual inclination of buccal surface
Lingual Inclination of Mandibular Posterior Teeth
Permits good interdigitation of opposing maxillary and mandibular teeth in ICP
Applies to molars and premolars
Mandibular 1st Premolar
Long, sharp buccal cusp
Very small lingual cusp
ML developmental groove
Mandibular 2nd Premolar
Only premolar with 3 cusps
Buccal cusp is largest
ML cusp > DL cusp
Location of ICP Contacts
Introduction to ICP Contacts
Supporting Cusps in ICP
The Picket Fence
: a Model for Locating ICP Contacts
Where would you expect to see ICP contacts on #13?
Which is the supporting cusp?
Where do opposing supporting cusps contact this tooth?
#13 ICP Contacts
Lingual cusp is the supporting cusp
Contacts on each marginal ridge made by opposing supporting cusps