pulp, pulp cavity, root canal anatomy, endodontics, pulp space, pulp horns, morphology of root canal, access opening, access cavity

1. ANATOMY OF THE PULP
SPACE & ACCESS
CAVITY
Dr. Hadia Arshad

2. PULP

4. PULP
Pulp is a soft tissue of
mesenchymal origin residing
within the pulp cavity

5. PULP CAVITY
The entire internal space or central cavity
enclosed by dentine except at the apical
foramen.
It consists of the following entities.
Pulp chamber
Root Canals

7. PARTS:
 ROOF
 PULP HORNS
A pulp horn is an accentuation
of the pulp chamber directly under
a cusp or a developmental lobe.
 FLOOR
 CANAL ORIFICE
PULP CHAMBER

8. Portion of the pulp cavity from the canal
orifice to the apical foramen
Consists of 3 sections:
Coronal
Middle
apical
ROOT CANAL

9. LATERAL AND
ACCESSORY CANALS

10. It is the most tapered portion
of the root
ANATOMICAL APEX RADIOGRAPHIC APEX
APEX

11. APICAL FORAMEN:
It is the terminal end of the pulp space by which it
communicates with the periapical region
MINOR CONSTRICTION: Narrowest portion at the
terminal end of the pulp space. It is said to coincide with
the cemento–dentinal junction.
ACCESSORY FORAMEN: Openings of accessory and
lateral canals
FORAMEN

12. Delta formation describes
the primary or secondary
canal that terminates short
of the apex with lateral
canals fanning out from this
point to end of the root
surface.
branching pattern of small accessory
canals and minor foramina seen at
the tip or apex of some tooth roots
APICAL DELTA

14.  Round
 Ribbon
 Figure eight
 Ovoid
 Bowling Pin
 Kidney bean
 C shape
CANAL MORPHOLOGIES
(IN CROSS SECTION)

15. VERTUCCI’S
CLASSIFICATION

16. WEINE’S
CLASSIFICATION

17. ACCESS CAVITY
PREPARATION

18. Part of the cavity from
occlusion table to the canal
orifice
DEFINITION

19. ACCESS OPENING

20. I. Locating all the canals
II. Straight line access of the instruments
III. Removal of the chamber roof and all coronal pulp tissues
IV. Conservation of the tooth structure
V. Well prepared and correct access cavity allow complete
irrigation, shaping ,cleaning and quality obturation
OBJECTIVES

21. 1. OUTLINE FORM
2. CONVIENCE FORM
3. CARIES REMOVAL
4. TOILET OF CAVITY
PRINCIPLES

22. BURS with high speed hand pieces
• Fissure bur: outline form
• Round bur: de-roofing
• Taper non cutting bur: refining
INSTRUMENTS

24. 1. Knowledge of pulp anatomy and morphology
2. Radiographs/digital imaging
3. Sharp endodontic explorer
4. Long shanked slow speed burs
5. Ultrasonic instruments for troughing
6. Dye staining
7. Irrigation
8. Transillumination
9. Enhanced vision with loupes and microscopy
AIDS IN LOCATION

25.  First Law of Orifice Location
It states that the orifices of the root canal are always located at the junction of
the walls and the floor.
 Second Law of Orifice Location
It states that the orifices of the root canals are always located at the angles in
the floor-walls junction.
 Third Law of Orifice Location
It states that the orifices of the root canals are always located at the terminus
of the root's developmental fusion lines.
 Law of Symmetry
The orifice are located perpendicular or equidistant from a line drawn in the
mesio-distal direction across the pulp chamber floor
 Law of Color Change
It states that the pulp chamber floor is always darker in color than the walls.
LAWS OF ORIFICE LOCATION

27.  AVERAGE TOOTH LENGTH: 23 mm
 NUMBER OF ROOTS AND CANALS: It has a single
canal and a single apical foramen
 ACCESS OPENING: always on lingual surface of
tooth, large triangular funnel shaped coronal
preparation
 CLINICAL SIGNIFICANCE: 75% roots are straight
MAXILLARY CENTRAL INCISORS

28.  AVERAGE TOOTH LENGTH: 22mm
 NUMBER OF ROOTS AND CANALS: single
canal and a single apical foramen
 ACCESS OPENING: from the lingual surface just
above the cingulum, triangular in shape
 CLINICAL SIGNIFICANCE: 53% of roots have a
distal curvature
MAXILLARY LATERAL INCISORS

29.  AVERAGE TOOTH LENGTH: 26mm
 NUMBER OF ROOTS AND CANALS: 1 canal
 ACCESS OPENING: ovoid access
MAXILLARY CANINES

30.  AVERAGE TOOTH LENGTH: 21mm
 NUMBER OF ROOTS AND CANALS: mostly one
root and one root canal
 ACCESS OPENING: triangular
MANDIBULAR CENTRAL INCISORS

31.  AVERAGE TOOTH LENGTH: 22mm
 NUMBER OF ROOTS AND CANALS: 1 canal
 ACCESS OPENING: from the lingual surface,
triangular in shape
 CLINICAL SIGNIFICANCE: roots may curve distally
MANDIBULAR LATERAL
INCISORS

32.  AVERAGE TOOTH LENGTH: 25mm
 NUMBER OF ROOTS AND CANALS: mostly one
 ACCESS OPENING: ovoid in shape
 CLINICAL SIGNIFICANCE: 43% have 2 roots and 2 canals
MANDIBULAR CANINES

33. STEPS IN PREPARATION
Removal of Caries and Permanent Restorations
Removed early, before the pulp chamber is entered.
This minimizes the risk of contamination.
To permits straight line access and prevents the restorative
fragments from becoming lodged in the root canal system.
Initial External Outline Form
Begin in the center of lingual surface of anatomic crown.
No 2 or 4 round bur or tapered fissure bur is used with a high
speed hand
The bur is directed perpendicular to the lingual surface as the
external outline opening is created.

34. Penetration of the Pulp Chamber Roof
change the angle of the bur from perpendicular to the lingual
surface to parallel to the long axis of the tooth.
Penetration into the tooth is accomplished along roots long
axis, frequently a drop-in effect is felt when the penetration
occurs.
Complete Roof Removal
the remaining roof is removed with the end of a round bur
under the lip of the dentin roof and cutting on the bur ‘s
removal stroke.
After hemorrhage has been controlled, all of the pulp chamber
roof, with pulp horns, must be removed and all internal walls
must be flared to lingual surface of the tooth.
STEPS IN PREPARATION

35. Identification of All Canal Orifices
the canal orifice are located with an endodontic explorer
Lingual Shoulder-: this is the lingual shelf of dentin that extends
from the cingulum to a point approximately 2mm apical to the
orifice.
Straight line access determination
Ideally, an endodontic file can approach the apical foramen or the
first point of the canal curvature.
Visual inspection of the access cavity
evaluate the access cavity using appropriate magnification and
illumination.
Refinement and smoothing of restorating margins
STEPS IN PREPARATION

37. FINAL SHAPE
INCISORS CANINES

39.  AVERAGE TOOTH LENGTH: 21mm
 NUMBER OF ROOTS AND CANALS:
 1st premolar: Generally has 2 root with 2 canals, but in the
case of 1 root has 2 canals which open in a common apical
foramen.
 2nd premolar: one root and one canal and sometimes has
an apical distal curvature.
 ACCESS OPENING: access is ovoid shaped in bucco-
lingual direction
pulp broad buccolingually and narrow mesiodistally
MAXILLARY PREMOLARS

40.  AVERAGE TOOTH LENGTH: 22mm
 NUMBER OF ROOTS AND CANALS:
 1st premolar: 1 root
 2nd premolar: one root and one canal
 ACCESS OPENING: ovoid- shaped extending from
cusp tip to cusp tip through occlussal surface
 CLINIAL SIGNIFICANCE: Because of the
inclination of the crowns of mandibular teeth and
the smaller lingual cusp, the access opening should
be placed buccal to the central fissure.
MANDIBULAR PREMOLARS

41.  AVERAGE TOOTH LENGTH:
 1st molar: 20.8mm
 2nd molar: 20mm
 NUMBER OF ROOTS AND CANALS:
 1st molar: Three roots and four canals
 2nd molar: usually three canals
 ACCESS OPENING: “Flattened” triangular outline form.
-base of triangle toward buccal
- apex of triangle toward palatal
- orifice positioned at each angle of the triangle
- access cavity is entirely within mesial half of the tooth
MAXILLARY MOLARS

42.  AVERAGE TOOTH LENGTH:
 1st molar: 21mm
 2nd molar: 19.8mm
 NUMBER OF ROOTS AND CANALS:
 1st molar: 2 roots, one mesial and one distal and 3 canals
 2nd molar: the same
 ACCESS OPENING: rhomboid/quadralateral shape of
access to allow for exploration of second distal canal
access cavity within mesial half of tooth
MANDIBULAR MOLARS

43. Determine shape and size of the opening on radiograph
Remove all caries and existing restorations
Determine the starting point into enamel usually midway between
he mesial and distal boundaries
Penetrate the enamel with a no.4 round bur and prepare the eternal
outline form using the pull stroke
After feeling the drop in thr chamber, completely remove all the
dentine and pulp
Explore the floor with a sharp endodontic explorer to locate the
canal orifice
Remove any obstruction if present
Smooth and finish the walls of the cavity
STEPS IN PREPARATION

47. ERRORS
Incomplete removal of caries
Inadequate opening
Missed canals
Inability to negotiate blocked canals
Treatment of wrong tooth
Mutilation of coronal tooth, excessive removal

48. The aim of the access preparation is a good
endodontic result with restoration of
normal structure and function of the tooth.
CONCLUSION

49. THANKYO
U