Mandibular 2nd Premolar Flashcards
calcify
2.5 yrs
erupt
11-12yrs
root complete
13-14yrs
Compared to the 1st PM, the 2nd PM is…
larger
Facial view: height of contour
cervical 3rd
Facial view: facial cusp
tip is shorter and blunted
Facial view: mesial and distal cusp ridges
approximately equal in length
more rounded
Lingual view: lingual cusp
shorter than buccal cusp, but well developed and functional
Lingual view: lingual groove
may be present INSTEAD of a mesiolingual groove
Lingual view: 2 cusp type of tooth
-facial and lingual
-no lingual groove but developmental depression distolingually where distal cusp ridge joins the DMR
Lingual view: 3 cup type of tooth
mesiolingual and distolingual cusps divided by lingual groove
-mesiolingual cusp wider and longer
-distolingual smaller but sharp
Mesial view: facial cusp
shorter, FACIAL to root bisector
Mesial view: marginal ridge
horizontal; at right angle to long axis of tooth
Distal view: DMR
lower/more cervical than the MMR
Distal view: the crown tips _____ to the long axis of root
distally
You can see more of the occlusal surface from which view, mesial or distal?
distal
Occlusal view: outline shape
square
Occlusal view: 3 cusp type “Y”
-most common
-facial, ML, and DL cusps
-m, d, and central fossa
-no transverse ridges*
-3 grooves (m, d, L)
Occlusal view: U or H groove pattern
-2 cusps
-more rounded crown
*if lingual triangular groove radiates from the M and D fossae, H groove is present (more common)
The root is…
longer and wider, single root
The root may have a slight _____ inclination
distal
A distal depression in the ______ third of the root may be depression
middle
How many root canals?
1; less tendency to have divided canals than 1st PM
2 or 3 pulp horns
