MORPHOLOGY OF MAXILLARY
MOLARS
Dr. Saleem Shaikh
INTRODUCTION
They are the largest and the strongest maxillary teeth.
 Although the crowns are slightly shorter than the premolars, they are
greater in all other dimensions.
 The first molar usually appear in the oral cavity when the child is 6 yrs of
age.
 They erupt posterior to the second deciduous molar, hence it is not a
succedaneous tooth.
 The maxillary molar has four well developed cusps and a
Supplementary cusp.
It has three roots
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BUCCAL ASPECT
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The crown is roughly trapezoidal.
When the tooth is viewed from the buccal aspect with the buccal groove
at right angles to the line of vision, the distal surface can be seen because
the distobuccal line angle is obtuse.
The mesiobuccal and distobuccal cusps are seen. The mesiobuccal cusp
is broader. And the distobuccal cusp is more sharper, as its mesial and
distal slope meet each other at right angles.
A buccal groove separates the two cusps.
The mesial outline of the crown is straight and it curves occlusally as it
reaches the crest of contour of the mesial surface, which is its contact
area. This is seen at the junction of occlusal and middle thirds
BUCCAL ASPECT
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The distal outline is more convex
and spheroidal, the distal contact
area is in the middle of middle
third.
All three roots are seen from this
aspect
Lingual root is the longest.
The point of bifurcation of the two
roots is around 4 mm from the
cervical line (root trunk).
LINGUAL ASPECT
From this aspect only the lingual cusps are seen.
 The mesiolingual cusp is the largest and the longest cusp of the tooth.
 60 % of the lingual surface is made up of the mesiolingual cusp.
 The mesiolingual cusp is more sharp than the distolingual cusp.
 The mesial outline makes an angle of around 90o with the
Mesial surface.
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The distolingual cusp is very smooth and spheroidal, and
merges with the distal outline.
The fifth cusp is seen on the lingual surface of the
mesiolingual cusp, it may or may not be prominent.
known as CUSP OF CARABELLI
A lingual developmental groove is seen between the two
cusps.
MESIAL ASPECT
MESIAL ASPECT
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From this aspect, mesiobuccal, mesiolingual & cusp of carabelli is seen.
starting from the cervical line buccally the crest of curvature is seen in
the cervical third.
The buccal outline then may be a little concave followed by convexity
until the tip of the mesiobuccal cusp.
On the lingual outline the crest of curvature is seen in the middle third.
The lingual outline is smooth if the fifth cusp is not well developed or if
the fifth cusp is developed, the outline may have a depression of the
lingual cusp.
Two roots are seen from this aspect, the mesio buccal root is broad and
flattened
The level of bifurcation of the root is a little closer to the cervical line
than on the buccal surface.
DISTAL ASPECT
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As the crown tapers distally and is more
narrower on this surface, most of the buccal
surface can be seen.
It is very similar to the mesial aspect.
The distal marginal ridge is slightly lower
hence triangular ridges can be seen.
the distobuccal root is narrower than the
mesiobuccal hence all three roots are
visible from this aspect.
The lingual root is banana shaped.
OCCLUSAL ASPECT
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The outline of the molar from occlusal
aspect is rhomboidal.
The crown is wider mesially than distally
and wider lingually than buccally.
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All five cusps are seen, mesiolingual cusp
is the largest cusp, followed by the
mesiobuccal,distolingual and distobuccal.
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The two buccal cusps and the mesiolingual
cusp are the primary cusps. The
distolingual cusp is the secondary cusp.
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Primary cusps form the primary cusp
triangle
OCCLUSAL ASPECT
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Two major and two minor fossa are seen.
Major – central fossa and distal fossa
Minor – mesial and distal triangular ridge
Most characteristic feature of the
maxillary molar is its oblique ridge, which
runs from the mesiolingual cusp to the
distobuccal cusp.
This ridge is slightly reduced in height in
the center of the occlusal surface.
The mesial and distal marginal ridges are
seen on sides.
OCCLUSAL ASPECT
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The central fossa has a central pit, central
and buccal developmental groove are seen
in this pit.
Sometimes another groove from the
central fossa may cross the oblique ridge,
this is known as the transverse groove of
the oblique ridge.
The distal fossa has a distal obligue
groove and the lingual developmental
groove.
PULP CHAMBER
Pulp chamber is wide and has pulp horns
corresponding to the cusps.
The pulp chamber is rectangular in shape.
It usually has three roots and three canals,
the palatal canal is the largest.
The mesiobuccal root often has two canals.