about the aspects of mandibular and maxillay 2nd molar. also about the pulp cavity

1. DECIDUOUS MAXILLARY 2ND MOLAR
Made by: Jubin Babu, 3rd year BDS

2. Chronology chart

3. BUCCAL ASPECT
 The characteristics resembles those
of the permanent maxillary 1st molar,
but it is smaller
 The buccal view of this tooth shows
two well-defined buccal cusps with a
buccal developmental groove
between them.
 The crown is narrow at the cervix in
comparison with its M-D
measurement at the contact areas.
 The crown is much larger than that
of the first primary molar.

4. Buccal aspect contd..
 The root are slender, are
much longer and heavier than
those of maxillary first molar.
 The point of bifurcation
between the buccal roots is
close to the cervical lone of
the crown.
 The two buccal cusp are more
nearly equal in size and
development than those of
permanent maxillary 1st molar.

5. LINGUAL ASPECT
Lingually , the crown shows the
following three cusps;
1. The mesiolingual cusp,
which is large and well
developed
2. The distolingual cusp,
which is well developed (more
than primary 1st molar) and
3. A third supplemental cusp,
which is apical to the
mesiolingual cusp sometimes
called the tubercle of carabelli ,
or the fifth cusp

6. Lingual aspect contd..
 A well-defined
developmental groove
separates the mesiolingual
cusp from the distolingual
cusp and connects with the
developmental groove,
which outlines the fifth cusp.
 All three roots are visible
from this aspect.
 Lingual root is large and thick
in comparison with other
two roots.

7. MESIAL ASPECT
 The crown has typical molar
outline that resembles that of the
permanent molars very much.
 The crown appears short because
of its width buccolingually in
comparison with its length.
 The mesiolingual cusp of the
crown with its supplementary
fifth cusp appears large in
comparison with the mesiobuccal
cusp.

8. Mesial aspect contd.
 Mesiobucaal root from this aspect is broad and flat.
 The lingual root has somewhat same curvature as of
1st molar.
 The mesiobuccal root extends lingually far out
beyond the crown outline.
 The point of bifurcation between the mesiobuccal
root and the lingual root is 2 or 3 mm apical to the
cervical line of the crown

9. DISTAL ASPECT
 From both the distal and the mesial
aspect the outline of the crown
lingually creates a smooth, rounded
line, whereas a line describing the
buccal surface is almost straight
from the crest of curvature to the
tip of the buccal cusp.
 The distobuccal cusp and the
distolingual cusp are about the
same in length. The cervical line is
approximately straight , as was
found mesially.

10. Distal aspect contd..
 All three roots are seen from this aspect, although only
apart of the outline of mesiobuccal root may be seen,
since the distobuccal root is superimposed over it.
 The distobuccal root is shorter and narrower than the
other roots.
 The point of bifurcation between the distobuccal root
and the lingual root is more apical in location than any
of the other point of bifurcation.

11. OCCLUSAL ASPECT
 From the occlusal aspect, the
tooth resemble the permanent
first molar.
 It is somewhat rhomboidal and
has four well developed cusp:
mesiobuccal, distobuccal,
mesiolingual, distolingual and
fifth supplemental cusp
 The buccal surface is rather flat
with the developmental groove
between the cusp less marked
than that found on the first
permanent molar.

12. PULP CAVITY
 The pulp cavity consist of a
pulp chamber and 3 pulp canals
corresponding to three roots.
 These canals leave floor of the
chamber at the mesiobuccal
and distobuccal corners and
from lingual area.
 Pulp chamber has 4 pulpal
horns, a fifth horn projecting
from lingual aspect of
mesiolingual horn may be
present.
 Mesiobuccal pulp horn is
largest, pointed and extends
occlusally.

13.  Mesiolingual pulp horn is
second in size, when
combined with fifth horn it
presents a bulky
appearance.
 Distobuccal pulp horn is
third in size, joining
mesiolingual pulp horn as
slight elevation.
 Distolingual pulp horn is
shortest and extends only
slightly above occlusal level.

14. DECIDUOUS MANDIBULAR
2ND MOLAR
It has characteristics that resemble those of the
permanent mandibular first molar, although its
dimensions differ.

15. BUCCAL ASPECT
 How it differs from first molars?
 It has a narrow M-D calibration at the
cervical portion of the crown than at contact
level.
 The mandibular first permanent molar,
accordingly, is wider at the cervical portion.
 The roots are slender and long.
 They have a characteristic flare mesiodistally
at middle and apical thirds.
 The point of bifurcation of the roots starts
immediately below the CEJ.

16. LINGUAL ASPECT
 Two cusps of almost equal
dimensions seen, a short, lingual
groove is between them.
 The cervical line is relatively straight.
 The mesial portion of the crown
seems to be a little higher than the
distal portion, thus appears tipped
distally.

17. MESIAL ASPECT
 Outline of the crown resembles
permanent mandibular first molar.
 The crest of contour buccally is more
prominent
 Marginal ridge is high
 the lingual cusp is longer, or higher, than
the buccal cusp.
 The cervical line is regular
 The mesial root is unusually broad and
flat with a blunt & apex sometimes
serrated

18. DISTAL ASPECT
 The crown is not as wide distally as it is
mesially; therefore, the mesiobuccal and
distobuccal cusp from the distal aspect.
 The distolingual cusp appears well
developed, and the triangular ridge is
seen over the distal marginal ridge.
 The distal marginal ridge dips down more
sharply and is shorter buccolingually than
the mesial marginal ridge.
 This cervical line of the crown is regular

20. Distal aspect contd..
 The distal root is almost as
broad as the mesial root is
flattened on the distal
surface.
 The distal root tapers more at
the apical end than does the
mesial root

21. OCCLUSAL ASPECT
 The occlusal outline is somewhat
rectangular
 The three buccal cusps are similar is
size.
 The two lingual cusps are also equally
matched.
 Well-defined triangular ridges seen
 The distal triangular fossa is not as
well defined as the mesial triangular
fossa.
 The mesial marginal ridge is better
developed and more pronounced than
the distal marginal ridge

22. PULP CAVITY
 Pulp cavity is made up of a
chamber & usually 3 pulp
canals.
 The two mesial pulp canals
are confluent as they leave
floor of pulp chamber
through a common orifice.
 Distal canal is constricted in
the centre.

23.  Pulp chamber has 5 pulpal
horns corresponding to 5
cusps.
 Mesiobuccal and mesiolingual
pulp horns are largest.
 Distobuccal horn is smaller
than mesial horns.
 The distal horn is shortest and
smallest occupying a position
distal to distobuccal horn.

24. How its different from permanent ?
 In the deciduous molar the mesiobuccal, distobuccal
and distal cusp are almost equal in size and
development.
 The distal cusp of the permanent molar is smaller
than the other two.
 Because of the small buccal cusps, the deciduous
tooth crown is narrower buccolingually, in
comparison with its mesiodistal measurement , than
is the permanent tooth.