The document provides information about permanent mandibular second and third molars. It discusses the vision and mission of the Faculty of Dentistry, which aims to educate graduates to compete internationally in preventive and therapeutic dentistry. It then summarizes key learning objectives about identifying features of tooth anatomy. The bulk of the document describes in detail the chronology, anatomy, landmarks, and aspects of the permanent mandibular second and third molars.

1. Faculty of Dentistry

2. Vision:
Following the outstanding innovations in the dental
sector we are aiming to create generations of
educationally, practically & ethically qualified
graduates who are capable of competing and facing
national and international challenges in preventive and
therapeutic dentistry

3. Mission:
Faculty of Dentistry is responsible for providing recent
educational programs & advanced facilities to initiate and
develop oral health professionals comparable to the prestigious
dental institutions graduates world-wide & participate positively
in dental community services.

4. By the end of this lecture, the student would be able to:
1-Recognize functions and chronology of the tooth.
2-Describe geometric outline of different aspects of the tooth.
3-Mention different anatomical landmarks of different aspects of
the tooth .
4- Identify the tooth as right or left.
5-Realize morphology of the tooth pulp cavity

5. Title: PERMANENT MANDIBULAR
SECOND & THIRD MOLARS
Prepared By: Dr. Saher Mohammed
Assistant Professor of Oral Biology
Presented & Edited By: Dr. Mary Moheb
Lecturer of Oral Biology

6. PERMANENT
MANDIBULAR
SECOND MOLAR

7. Chronology of LOWER 7:
Enamel organ appearance 1 year
Beginning of calcification 2.5-3 years
Crown completed 7-8 years
Eruption 11 -13 years
Root Completion 14-15 years
4 lobes

8. It has five
aspects

9. MCA & DCA are located in the middle third
One groove: Buccal developmental groove
may end in false buccal pit.
MB cusp is longer than the DB cusp.
The two buccal cusps are nearly
equal in size
Buccal aspect
-The crown is smaller than that of first molar
in MD & occlusocervical dimensions
-Parts from the longer sharp pointed lingual
cusps can be seen from buccal aspect (buccal
cusps are flatter)
The roots are smaller, shorter, less divergent
and nearly parallel with longer root trunk and
more pointed apex than lower 6

10. M D
The two lingual cusps are more
pointed than buccal cusps.
Anatomical Landmark: Lingual
developmental groove (fades out)
Longer root trunk with a
developmental depression.
Lingual aspect

11. The geometric outline:
Rhomboid
MMR is more occlusally
positioned than DMR (2 cusps can
be seen)
L
B
Mesial aspect
The mesial root is only seen with
longitudinal depression

12. L B
Distal root is narrower than mesial
root, so both roots are seen
Distal aspect
DMR is more cervically positioned
than MMR ( 4 cusps can be seen)
DCA centered buccolingually and
occlusocervically

13. The geometric outline
Rectangular with slight lingual
convergency
M
L
B
D
The crown is larger Mesio-Distally than
bucco -lingually.
Occlusal aspect
Distal convergence

14. M
L
B
D
Anatomical landmarks:
Elevations:
4 cusps with 4 triangular ridges
( mesial cusps are larger than distal
cusps).
Mesial and distal marginal ridge.
Occlusal aspect

15. Central fossa with central pit
Mesial and distal triangular fossae
Mesial and distal pits
Cross shaped occlusal groove (cruciform
pattern) composed of central groove
crossed by buccal and lingual
developmental grooves dividing occlusal
surface into nearly equal 4 lobes
M
B
D
L
Supplemental grooves radiate from
developmental grooves
Depressions

16. Is four or
five cusps
type

17. Chronology of LOWER 8:
Enamel organ appearance 4 years
Beginning of calcification 8-10 years
Crown completed 12-16 years
Eruption 17 -21 years
Root Completion 18-25 years
4 or 5 lobes

18. It has five
aspects
Four cusp
type is more
likely to be
in good
occlusion
with other
teeth

19. M
D
2 Short roots (shorter than lower 6
& 7) may be fused in all or part of
their length
The roots are more inclined distally
than 1st and 2nd molars
Buccal aspect
MCA is in the middle third while DCA
is absent

20. L
B
The MB cusp tip is close to the ML
cusp tip giving a small occlusal table
L B
There is a distal convergence
( distobuccal & distolingual)
Distal root is narrower than mesial
root, so both roots are seen
Mesial aspect
Distal aspect

21. The geometric outline:
Rectangular or pentagonal
There are numerous supplemental
grooves (wrinkled appearance)
occlusal aspect

22. Thank You