Upload
vfacto
View
226
Download
0
Embed Size (px)
Citation preview
8/4/2019 (Oral Ana) Man 3rd Molars
1/39
Mandibular
Permanent molars
Reporters:Ciarra Jansen Rodrigez
Janine Villas
Virginia
Kyra Jean Blacano
8/4/2019 (Oral Ana) Man 3rd Molars
2/39
Arch traits
2 roots; M & D
4 major cusps & 1 lesser-sized5th cusp
(in 1st
molars) Crowns broader MD than BL
The 2 L cusps are of equal size
MB & DB cusps are of equal size
8/4/2019 (Oral Ana) Man 3rd Molars
3/39
Mandibular
3rd molar
8/4/2019 (Oral Ana) Man 3rd Molars
4/39
Mandibular 3rd molar
8/4/2019 (Oral Ana) Man 3rd Molars
5/39
Dental Notation
Right Left
Palmers
Universal 32 17
Two digit 48 38
8 8
8/4/2019 (Oral Ana) Man 3rd Molars
6/39
Chronology
Permanent Mandibular 3rd Molar
Calcification 8 - 10 yrs
Crown complete 12- 16 yrsEmergence 17 21 yrs
Root complete 18 25 yrs
8/4/2019 (Oral Ana) Man 3rd Molars
7/39
Mandibular 3rd molar
Buccal aspect
Highly variable
Roots are short, fused & D inclined
Lingual aspect
Short crown of highly bulbous
outline Rounded cusps
8/4/2019 (Oral Ana) Man 3rd Molars
8/39
Mandibular 3rd molar
Mesial B & L profiles are highly convex
Distance between apices of M cusps is
shorter Distal
Almost entire B surface is visible
D root is the narrowest BL & shortestof all mandibular molars
8/4/2019 (Oral Ana) Man 3rd Molars
9/39
Pulp
similar to mandibular 2nd molar
BL section Usually 2 canals in M root
Sometimes 1 canal in M
root
T-section
M dimension > D
Mandibular 3rd molar
8/4/2019 (Oral Ana) Man 3rd Molars
10/39
Mandibular 3rd molar
Occlusal aspect
Ovoid in outline
M half is wider BL than D half
B & L Profiles converge D Highly restricted occlusal table in
MD & BL dimensions (type trait)
4 narrow conical cusps
Highly convex MRs
Irregular pit/groove pattern
Shorter grooves
8/4/2019 (Oral Ana) Man 3rd Molars
11/39
Type traits
8/4/2019 (Oral Ana) Man 3rd Molars
12/39
8/4/2019 (Oral Ana) Man 3rd Molars
13/39
Buccal aspect
Mandibular 2nd Molar
-From this aspect the
crown is shorter cervico-
occlusally
- Two buccal cusps are seen:
mesiobuccal cusp anddistobuccal cusp
- Both the cusps are equal in
size
- Buccal developmental
groove separates the two
buccal cusps
Mandibular 3rd Molar
- From this aspect the toothvaries considerably.
- The four cusp type has two
buccal cusps
- The buccal cusps are
shorter and rounded
- Both the cusps are equal in
size
8/4/2019 (Oral Ana) Man 3rd Molars
14/39
Buccal aspect
Mandibular 2nd Molar Mandibular 3rd Molar
8/4/2019 (Oral Ana) Man 3rd Molars
15/39
Lingual aspect
Mandibular 2nd Molar
- Two lingual cusps areseen: mesiolingual cusp and
distolingual cusp
- lingual developmental
groove separates the twolingual cusps
- Crown and root converge
lingually but to a lesser
degree
Mandibular 3rd Molar
- A well developed 3rd molarclosely resembles a 2nd
molar except for the size
and root development
8/4/2019 (Oral Ana) Man 3rd Molars
16/39
Lingual aspect
Mandibular 2nd Molar Mandibular 3rd Molar
8/4/2019 (Oral Ana) Man 3rd Molars
17/39
Mesial aspect
Mandibular 2nd Molar
- The mesiodistalmeasurement is a fraction
less than 1stmolar
- The cervical ridge on the
buccal surface is lesspronounce
- The cervical line is less
curved, being straight
Mandibular 3rd Molar
- From this aspect 3rd molarresembles 2nd molar except
for its dimensions
8/4/2019 (Oral Ana) Man 3rd Molars
18/39
Mesial aspect
Mandibular 3rd MolarMandibular 2nd Molar
8/4/2019 (Oral Ana) Man 3rd Molars
19/39
Distal aspect
Mandibular 2nd Molar
- When compared with 1st
molar this aspect doesnt
have distal cusp and
distobuccal groove
Mandibular 3rd Molar
- From this aspect too thistooth resembles 2nd molar
except for its dimensions
8/4/2019 (Oral Ana) Man 3rd Molars
20/39
Distal aspect
Mandibular 3rd MolarMandibular 2nd Molar
8/4/2019 (Oral Ana) Man 3rd Molars
21/39
Occlusal aspect of Mandibular 3rd molar
When fully developed the occlusal aspect of 3rd molar is
quite similar to the 2
nd
molar
Occlusal aspect
8/4/2019 (Oral Ana) Man 3rd Molars
22/39
Roots
Mandibular 2nd Molar
- The tooth has two welldeveloped roots; one mesial
and one distal
- They are broad
mesiodistally but not asbroad as 1stmolar
- They are inclined distally
Mandibular 3rd Molar
-- Roots are short andpoorly formed
-- An average tooth shows
two roots; one mesial and
one distal
-- They may be separated or
fused
8/4/2019 (Oral Ana) Man 3rd Molars
23/39
Anomalies of
Mandibular 3rd molar
8/4/2019 (Oral Ana) Man 3rd Molars
24/39
Anomalies of Mandibular 3rd molar
IMPACTED 3RD MOLAR
8/4/2019 (Oral Ana) Man 3rd Molars
25/39
Deciduous Mandibular
1st and 2nd Molar
8/4/2019 (Oral Ana) Man 3rd Molars
26/39
Deciduous mandibular 1st molar
Deciduous mandibular 1st molar
8/4/2019 (Oral Ana) Man 3rd Molars
27/39
Dental Notation of Deciduous Tooth
1st Molar 2nd Molar
R L R L
Palmers
Universal S L T K
Two Digit 84 74 85 75
D D E E
8/4/2019 (Oral Ana) Man 3rd Molars
28/39
Chronology
Deciduous Mandibular 1st Molar
Calcification (weeks in utero) 15
Crown complete 5 months
Eruption 16 months
Root complete 2 yrs
8/4/2019 (Oral Ana) Man 3rd Molars
29/39
Chronology
Deciduous Mandibular 2nd Molar
Calcification (weeks in utero) 18
Crown complete 10 months
Eruption 27 months
Root complete 3 yrs
8/4/2019 (Oral Ana) Man 3rd Molars
30/39
Set traits More bulging B & L cervical ridges
Constricted cervix
Buccal cervical ridges on deciduous
molars
Occlusal aspect: constricted occlusal table
8/4/2019 (Oral Ana) Man 3rd Molars
31/39
Deciduous dentition
Set traits
Smaller in size
Smaller crown height/toothlength ratio
Greater crown width/heightratio
8/4/2019 (Oral Ana) Man 3rd Molars
32/39
Deciduous dentition
Set traits
Molar roots
More slender & relatively longer
More bowed & flared outward
Shorter root trunk
Milk-white in color
Enamel is thinner & pulp chamber islarge
Some class, arch & type traits in permanentdentition are applied to deciduous dentition
Only new traits will be discussed
8/4/2019 (Oral Ana) Man 3rd Molars
33/39
Mandibular 1st molar
Molariform unlike max. 1st
4-cusped tooth
Buccal aspect 2 cusp: MB & DB
M half > D half M half projects more occlusally &
occupies 2/3s of crown area
M profile is straight
D profile is curved and overhanging
CL inclines downward from D to M
Roots
2 divergent roots; M & D
M is longer
8/4/2019 (Oral Ana) Man 3rd Molars
34/39
Mandibular 1st molar
Lingual aspect 2 cusps: ML & DL
ML cusp is conical & larger
than DL Outlines of B cusps are visible
CL is more straight &
horizontal than that of the B
aspect
8/4/2019 (Oral Ana) Man 3rd Molars
35/39
Mandibular 1st molar
Mesial aspect
Buccal cervical ridge (BCR)
From MB cusp tip a straight incline toBCR
Transverse ridge connecting MB & ML
M MR is high & prominent
Mesial marginal groove separates M MRfrom ML cusp ridge
CL is convex occlusally & lower on the Bend
Root
Extremely broad BL (sometimes asbroad as the crown)
Frequently bifid apex
8/4/2019 (Oral Ana) Man 3rd Molars
36/39
Mandibular 1st molar
Distal aspect All 4 cusps & M root profiles
are visible
B profile is less bulging than
from mesial aspect
D MR is lower and less
prominent than M MR
CL is more straight &horizontal than that of M
aspect
8/4/2019 (Oral Ana) Man 3rd Molars
37/39
Mandibular 1st molar
Occlusal aspect
Without the BCR, it is rectangular
BL width is grater from M than D
MB cusp is the largest, followed by ML,DB & DL
M Transverse groove, interrupted by Central groove; extends from M pit to
central pit
M pit
2 supplemental grooves; of which MLcrosses M MR
Central pit
B& L grooves
Often a D pit
8/4/2019 (Oral Ana) Man 3rd Molars
38/39
Mandibular 2nd molar
Morphologically considereda model for the permanent1st mandibular molar
Allows prediction of what
the 1st
mandibular molarwill look like
This concordance is calledisomorphy
Set traits Cervical constriction
Cervical 1/3 bulging
Little root trunk
Roots thinner & divergent
8/4/2019 (Oral Ana) Man 3rd Molars
39/39
Thats All !!!