mandibular pre-molars Flashcards
Functionally resembles canine;
mandib 1st pre-molar
mandib 1st pre-molar
no significant lingual cusp; shorter root
Larger crown and root than first premolar;
2nd mandib pre molar
functionally resembles molar
Mandibular Second Premolar
(One B cusp and one L cusp)
H and U type
mandib 2nd pre molar
most common type of Mandibular Second Premolar
Y-type
Y-type
One B cusp and two L cusps
leeway’s space
Space gained by the difference in mesiodistal dimensions of the premolars and the primary molars
sharp well defined cusp and similar to canine
buccal aspect of mandib 1st pre molar
tf mand 1st pre molar has a bell shaped crown
T
mesial ridge longer than distal ridge of mand 1st pre molar(buccal view)
f
shorter
mesial slope of mand 1st pre molar
has a concavity
tf mand 1t pre molar has no developmental depressions or concavities
f
Distinct facial lobes and developmental depressions
tf
CEJ is flat on mand 1st pre molar
F
CEJ slightly convex toward apex but less than anterior teeth
tf lingual cusps are huge on mand 1st pre molar
f they are small and permit occlusal surface to be visible
mesialdistally ligual surface narrower than buccal
mandibular 1st pre molar
tf
only 1 surface visible on lingual aspect of mand 1st premolar
F multiple surfaces
ridges visible on lingual aspect of mand 1st pre molar
buccle triangular rdge and transverse ridge
tf only distal marginal ridge visible from lingual aspct of mand 1st pre molar
f
distal and mesial
mand 1st premolar
Lingual height of contour almost —— on the crown
Lingual height of contour almost centered on the crown
unique to mandib 1st pre molar
Prominent mesiolingual developmental groove
mesial aspect of mand 1st pre molar
Crown inclines—– over the root
Crown inclines lingually over the root
tf short lingual cusp tipps the Occlusal plane is “tipped” lingually in mand 1st pre molat
T
tf
mesial marginal ridge of mand 1st pre molar
is perpendicular to long axis of tooth
f
mesial marginal ridge is the only marginal ridge of all posterior teeth not perpendicular to long axis of tooth
centered over root vs centered over lingual border of tooth of mand 1st pre molar
buccal cusp vs. lingual cusp
which developmental groove is visible from mesial aspect of mand 1st pre molar
ML developmental groove
tf
transverse ridge presense will prevent central grove from being visible of mand 1st pre molar
T
sloped mesial marginal ridge of mand 1st pre molar allows for
More of the occlusal surface visible
distal aspect of mand 1st pre molar
Wider buccolingually than mesial surface
tf on distal aspect of mand 1st pre molar
Distal marginal ridge perpendicular to the long axis
t
tf on mand 1st pre molar
mesial marginal ridge more occlusally positioned than
distal marginal ridge
f
Distal marginal ridge perpendicular to the long axis (and more occlusally positioned than mesial marginal ridge)
mesial aspect of mand 1st premolar
more occlusal surface visible than distal aspect
less curved CEJ
distal over mesial of mand 1st pre molar
in line with buccal cusp and apex
contact area of mandib 1st pre molar
mand 1st pre molar distal aspect
Contact area slightly broader than the mesial
Diamond shaped outline form
occlusal aspect of mand 1st pre molar
Prominent buccal ridge but uniformly convex buccal outline with much of the buccal surface visible
occlusal of mand 1st pre molar
distal outline more rounded and convex
than mesial outline of mand 1st premolar
convex with indentation
Mesial outline of mand 1st pre molar
indentation of mand 1st pre molar
where ML groove is located;
Prominent line angles but rounded
occlusal of mand 1st pre molar
small lingual cusp
mand 1st pre molar
central grove of mand 1st pre molar
often not distinct
transverse ridge of
occlusal of mand 1st pre molar
tf only mesial fossa of mand 1st pre molar visible
f
mesial and distal fossa
which marginal ridge is shorter on mand 1st pre molar
mesial or distal
mesial
both converge to lingual)
mesial and distal marginal ridge of mand 1st pre molar