2. INTRODUCTION
For the success of an endodontic therapy, the
knowledge of pulp anatomy cannot be ruled out. It is
essential to have kbowledge about normal
configuration of pulp cavity and its variations.
As the external morphology of the tooth changes, so
does the internal morphology.
3. PULP CAVITY
The pulp cavity is the central cavity within a tooth
and is entirely enclosed by dentin except at apical
foramen.
It is divided into:
1. Coronal portion pulp chamber
2. Radicular portion root canal
4. PULP CHAMBER
Occupies the coronal portion of pulp cavity.
In anterior teeth, the pulp chamber gradually merges
into the root canal and the division becomes
indistinct.
In multi-rooted tooth, pulp cavity consists of a single
pulp chamber and usually 3 or more root canals.
ROOF OF PULP CAVITY: consists of dentin covering
the pulp chamber occlussaly or incisally.
5. PULP HORN : Accentuation of the roof of pulp
chamber directly under a cusp or developmental
lobe.
FLOOR OF PULP CHAMBER: runs parallel to the
roof and consists of dentin bounding the pulp
chamber near cervical area of tooth, particularly
dentin forming the furcation area.
6. CANAL ORIFICES: openings in the floor of pulp
chamber leading to the root canals.
They are not separate structures but are continuous
with the pulp chamber and root canals
7. ISTHMUS
“A narrow passage or anatomic part connecting two
larger structures (root canals) “
Identified using METHYLENE BLUE DYE
Contains pulp or pulpally derived tissue and acts as
store house for bacteria
Therfore should be well prepared and filed
8. Hsu n Kin 1997 classified isthmus as:
Type I
Type II
Type III
Type IV
9. ROOT CANALS
“Portion of the pulp cavity from the canal orifice to the
apical foramen”
Parts:
Apical constriction
(minor diameter)
Apical foramen
(major diameter)
Cemento-dentinal junction
Accessory canals
Lateral canals
10. CLASSIFICATIONS
VERTUCCI’S CLASSIFICATION:
1. Type I: 1 canal extends from the pulp chamber to
apex. (1)
2. Type II: 2 separate canals leave the pulp chamber
and join short of apex to form 1 canal(2-1)
3. Type III: 1 canal leaves the pulp chamber and
divides into 2 roots; the two then merge to exit as 1
canal. (1-2-1)
11. 4. Type IV: 2 separate distinct canals extend from the
pulp chamber to apex. (2)
5. Type V: 1 canal exits the pulp chamber and divides
short of the apex into 2 separate canals with
separate apical foramina. (1-2)
6. Type VI: 2 separate canals leave the pulp chamber,
merge in the body of root and redivide short of
apex to exit as 2 distinct canals. (2-1-2)
12. 7. Type VII: 1 canal leaves the pulp chamber, divides
and then rejoins in the body of root and finally
redivides into 2 distinct canals short of the apex.
(1-2-1-2)
8. Type VIII: 3 separate distinct canals extend from
pulp chamber to apex (3)
15. Classification of C-shaped canals
1. Melton’s classification
I- C shaped outline without seperation
II- Semicolon (;) shaped with distinct mesial canal
III- two or more discrete canals
16. 2. Fan’s classification
I- C shaped outline without seperation
II- Semicolon (;) shaped with distinct mesial canal
(but α or β >60 )
III- two or more discrete canals
(but α or β <60 )
IV- only 1 oval canal
V- no canal could be observed
(usually near the apex)
18. METHODS OF DETERMINING PULP
ANATOMY
1. CLINICAL METHODS
I. Anatomy studies
II. Radiographs
III. Explorations
IV. High resolution compound tomography
V. Visualisation endogram
VI. Fiberoptic endoscope
VII. Magnetic resonance imaging
19. 2. IN VITRO METHODS
i. sectioning of teeth
ii. use of dyes
iii. Contrasting media
iv. Scanning electron microscope analysis
20. VARIATIONS IN INTERNAL ANATOMY
Variations in development
i. Gemination
ii. Fusion
iii. Concrescence
iv. Taurodontism
v. Talon’s cusp
vi. Dilaceration
vii. Extra root canal
viii. Dens invaginatus
ix. Dens evaginatus
23. In most cases, the number of root canals corresponds
with the number of roots.
Sometimes there may be an additional canal:
1. Mesial root of mandibular 1 molar almost always
has 2 canals
2. Distal root of mandibular 1 molar, ocassionally has
2 canals
3. Mesiobuccal root of maxillary 1 molar has
frequently 2 canals
4. Mandibular premolar may have 2 canals
1 faint communication
2 complete isthmuswith definite connection
3 complete but very short isthmus
4 complete/incomplete b/w 3 or more canals
5 2 or 3 without visible connections
Af- dist b/w major n minor dia is 0.5-0.7
Cdj- 0.1 mm from af
Delta- triangular area of root; main canal accessory canals and periradicular tissue