Obturation of root canal system

1. Obturation Of Root Canal
System
It is essential, that endodontic therapy must .
include sealing of the root canal system to
prevent tissue fluids from percolating in
the root canal and prevent toxic by –
products from both necrotic tissue and
microorganisms regressing into the
.periradicular tissue
Ass.Prof.Dr.Mohamed ALsakkaf 1

2. The current accepted method of .
obturation of prepared canals
employs a solid or a semisolid core
such as gutta – percha and root canal
.sealer
2

3. The Objectives Of Obturation
To prevent percolation of periradicular .1
exudate into the pulp space via the apical
foramina and / or lateral and furcation
.canals
To prevent percolation of gingival exudate . 2
and microorganisms into the pulp space
via lateral canals opening into the
. gingival sulcus
3

4. To prevent microorganisms left in the canal . 3
after preparation from proliferating and
escaping into the periradicular tissue via
the apical foramina or / and lateral
. canals
To seal the pulp chamber and canal system . 4
from leakage via the crown in order to
prevent passage of microorganism and /
or toxins along the root canal filling and
into the periradicular tissue via the apical
. foramina and / or lateral canals 4

5. So the quality of canal obturation .
: depends on
.The complexity of the canal system -
.The quality of canal preparation-
.The materials to be used
.The skills of the operator-
The restoration of the clinical crown to -
prevent leakage into the pulp chamber (Is
?(. obturation the final step in R.C.T
5

6. Timing Of Obturation
The canal obturation may be delayed for one .
or more visits after preparation to give time
for medicaments sealed into the canals to
reduce or eliminate the microbial population
and for the patients signs specially in
.complex cases
Teeth with little or no problems can be .
. prepared and filled in one appointment
6

7. Prerequisites for Filling the Root Cana l
Prerequisites for Filling the Root Cana
:A root canal can be obturated when
There is no pain, swelling, tenderness to percussion, 
.or fistulation associated with the tooth
The instrumented canal is dry and free of odor (no 
(exudates or purulent discharges into the canal
If the pulp is necrotic or a periapical lesion is 
present, the root canal cannot be filled before the
.second appointment
Teeth associated with procedural accident, 
perforation must not be filled until another treatment
.are made

8. EXTENSION OF THE ROOT CANAL
FILLING
Canals filled to the apical dentinocemental junction •
.are filled to the anatomic limit of the canal
Filling to the radiographic end of the root •

9. :Complicated Cases
Teeth with signs of apical periodontitis .1
(. (tenderness due percussion
.Radiographic signs of apical periodontitis . 2
.Teeth with excessive exudate. 3
9

10. .Teeth with purulent discharge. 4
Teeth associated with a procedural accident, . 5
. like perforation
Note: Some teeth with these problems can be
. treated in one visit
10

11. Materials Used For Obturation
A large number of materials have been used to .
obturate R.C.S ranging from orange wood
sticks through precious metals to dental
cements, but most materials that showed a
wild world usage are the Gutta – Percha and
. sealers
11

12. Root Canal Filling Materials
:Core material 
Solid materials : Silver point a.
.Semisolid materials: Guttapercha b.

13. Sealers: A root canal sealer is used in
combination with root filling materials
(gutta – percha(. Now the sealer has a
primary role in sealing the canal by
obliterating the irregularities between the
.canal wall and the core material
13

14. ?Why We Use Sealers
Root canal sealers are used with core filling
:materials for the following
Cementing (luting( the core material into .1
. the canal
Filling the discrepancies between the canal . 2
. walls and the core material
14

15. It acts as a lubricant to help in positioning . 3
. of core material
.Bactericidal agent. 4
Acting as a marker for accessory canals, .5
resorptive defects, and other spaces into
which the main core material may not
. penetrate
15

16. Requirement Of An Ideal Sealer
.a. Non – irritating to periapical tissue
.b. Insoluble in tissue fluids
.c. Dimensionally stable
16

17. .d. Hermetic sealing ability
.e. Radiopaque
.f. Bacteriostatic
g. Sticky and good adhesion to canal walls
. when set
17

18. .h. Easily mixed
.i. Non – staining to dentin
.j. Good working time
.k. Readily removable if necessary
18

19. :Note
There is no single material that satisfy . 1
. all requirements
Sealers are toxic and cause periapical . 2
irritation when freshly prepared but
. this reduced after setting
19

20. Most sealers are absorbable, so the .3
. volume must be minimum
Less viscous sealer should be forced by . 4
. core material into canal anastomoses
Excess sealer should ideally flow .5
. backwords out of the canal orifice
20

21. Types of Sealer
Sealers in use today can be divided into
.four groups based on their constituents
Zinc Oxide – eugenol sealers: .1
Commercial products include:
Tubliseal, Pulp canal sealer, Roth
. sealer
21

22. :Properties
Once set ZOE sealers form relatively .
weak materials, which are susceptible to
. decomposition
.Potential for sensitization.
.Mutagenic in extremely high doses.
22

23. These problems are not apparent -
. clinically
They are probably used more often than-
all the other sealer combined and give
. good results
The products have a range of setting -
time and flow properties to satisfy
(. filling difficult canals (slow set 23

24. :Calcium hydroxide sealers .2
The commercial products involve:
Sealapex, a calcium hydroxide –
.containing polymeric resin, and Apexit
24

25. :Properties
They preserve the vitality of the pulp stump .
and stimulate healing of hard tissue
. formation at the foramen
.Sealing ability is similar to ZOE.
Soluble and may leach out and weaken the .
remaining cement when expose to tissue
.fluid
25

26. :Resin Sealers .3
Like AH26 which consists of an epoxy
resin, which set slowly when mixed with an
. activator
:Properties
.Less popular than ZOE and Ca(OH(2.
26

27. .Good sealing and adhesive properties.
.It has antibacterial activity.
Give an initial severe irritation, which .
. subsides after some weeks
Strong mutagenic potential, which causes .
. allergy and paraesthesia
27

28. :Glass Ionomer Sealers .4
The products include: Ketac, Endo, Espe,
.Seefeid
:Properties
.Ability to adhere to dentine.
28

29. Less effective or no difference in the apical .
sealing properties when comparing with
.others
.Less coronal leakage, than ZOE.
Shear bond strength to Gutta – Percha is .
. similar to ZOE sealers
29

30. :Gutta – Percha
It is the most widely used and acceptable .
. obturating material
G.P is a form of rubber obtained from a .
number of tropical trees. It is
transpolyisoprene, which in its pure form
is hard, brittle and less elastic than natural
. rubber
30

31. It is mixed with variety of other .
materials to produce a blend G.P
(19 – 22%(, zinc oxide (59 – 75%( and
various waxes, coloring agents,
antioxidants and metal salts to provide
.radiopacity
31

32. :Advantages Of G.P
.Inert. 1
.Dimensionally stable. 2
.Non – allergic. 3
.Antibacterial. 4
32

33. .Non – staining to dentine. 5
.Radiopaque. 6
.Softened by heat. 7
.Softened by organic solvents. 8
.Removable from the R.S.C when necessary. 9
33

34. :Disadvantages Of G.P
.Lack of rigidity. 1
.Do not adhere to dentine. 2
.Can be stretched. 3
34

35. Obturation Techniques
:There are two main techniques.
(.Lateral Condensation (Cold. 1
(.Vertical Condensation (Hot. 2
35

36. Methods for Guttapercha
Application
.Lateral Condensation •
.Vertical Condensation •
.Thermomechanical Condensation •
Injection Techniques •

37. :Lateral Condensation. 1
.This technique is the most popular one .
The core of this technique is placing tapered .
Gutta – Percha cones in the canal and then
compacting them against the canal walls
. under pressure by using spreader
37

38. IT IS THE MOST POPULAR
.TECHNIQUE OF OBTURATION
INDICATIONS: Lateral Condensation of gutta- •
percha may be used in most cases, exception:
severely curved or abnormally shaped canals or
those with gross irregularities such as internal
.resorption
Three dimensional filling of the canal is
. obtained and bacterial tight seal

39. :Steps
After the R.C preparation finished, select .1
master Gutta – Percha. Cone whose size is the
same with the largest file used up to the working
length. One should feel the tugback with master
gutta – percha point. It should be notched at
working distance analogous to the level of
. incisal or occlusal edge reference
39

40. Radiographically make sure that the . 2
cone is fit. Remove the cone if it fit
. and insert it in NaOCL
40

41. If the cone is going beyond the foramen,
so select the larger number cone or cut
.it to the WL
41

42. Select the size of spreader to be used . 3
for L.C. It should reach 1 – 2mm of
. true WL
42

43. The cement (sealer) is mixed and given the 
spatula test to determine the desired
(.consistency (must be soft
The apical half of the master point (except the 
tip) is coated with sealer and inserted into the
.canal to the predetermined depth

44. Dry the canal using paper point and . 4
. apply sealer into the prepared R.C
44

45. The nominated and premeasured cone. 5
is coated with sealer and place into
the R.C. After placement of cone, a
selected spreader is placed into the
. canal alongside the cone
45

46. Spreader acts as a wedge to squeeze the
G.P laterally under vertical pressure
.not by pushing it sideways
46

47. Spreader then removed from the canal. 6
by rotating it back and forth. This
compacts the G.P and provide space
. lateral to the master cone
47

48. Place in the created space beside the . 7
master cone an accessory one, and
repeat the same procedure until the
spreader longer cannot penetrate
.beyond the cervical line
48

49. Protruding G.P points at canal orifice . 8
should be removed by using hot
. instrument
49

50. Advantages Of L.C Technique
.a. It can by used widely in most cases
b. It prevent overfilling by length control
. during condensation
50

51. Disadvantages
a. May not fill the canal irregularities
. efficiently
.b. Does not provide homogenous mass
51

52. C. Space may exist between master and
. accessory cones
52

53. Warm Lateral Condensation
It is a variant of traditional lateral condensation and is
especially indicated for teeth with internal resorptive
defects
A heated instrument is introduced into a tooth already obturated •
by lateral condensation to soften the gutta-percha mass and
.enhance adaptation to the internal anatomy of the canal
The Endotec instrument is then activated for 4 to 5 seconds •
and moved in short, continuous motions in and out of the gutta-
.percha mass
A cold spreader is introduced and rotated to condense the •
thermoplasticized gutta-percha into the canal anatomy
Accessory points coated with sealer are then added until the •
.canal is completely obturated

54. Vertical Condensation .2
Vertical Condensation by using warm .
G.P cones to fill the R.C is known as
.Schilders technique
54

55. Because in the R.C.S may present many.
lateral and accessory canals, which
make the R.C complex, the use of
the heated G.P cones, will be helpful
in the filling of these accessory canals,
by maximum amount of G.P and
.minimum amount of sealer
55

56. This technique requires the
:following
a) Continuous tapering funnel shape
. from orifice to apex
b) Apical opening kept as small as
. possible
56

57. c) Decreasing the cross sectional
diameter at every point apically and
. increasing at each point coronally
57

58. :Steps
After selection the master cone .1
according to shape and size of the
prepared canal, be sure that the
cone fit in 1 – 2mm of apical stop,
to avoid moving the heated cone
.apically
58

59. Radiographically confirm the fit of the. 2
cone, if fit, remove it and insert in
. NaOCL
.Irrigate and dry the canal. 3
59

60. Select the instrument for heating .4
(Plugger) according to the shape of
. canal
60

61. Apply little amount of sealer into the . 5
. canal
Cut the coronal end. 6
' .of selected G.P at canal orifice
61

62. Heat the plugger and force the G.P by . 7
it into the canal. The blunted end of
plugger provides a depression in the
center of master cone. The outer
walls of G.P then folded inward to
fill the central void, at the same time
mass of softened G.P is moved
apically, and laterally. This
procedure also removes 2 – 3mm
.of coronal part of G.P
62

63. 63

64. After completing apical filling, complete . 8
obturation by backfilling. Obturate the
remaining canal by heating small
segments of G.P and condense them by
. heated plugger
64

65. Do not apply sealer on the softened G.P,. 9
this will prevents their adherence to
. G.P present in the canal
Finally clean the pulp chamber with . 10
. alcohol to remove the remnants
65

66. 66

67. :Advantages Of Vertical Condensation
Good sealing of canal apically, laterally
.and obturation of accessory canals
67

68. Disadvantages
.a) Risk of vertical root fracture
.b) Overfilling
.c) Time consuming
68

69. Thermoplastic Injection Technique
Gutta-percha heated to 70 °C (158 °F) is injected into •
the root canal by means of a Peripress syringe, and
.is supposed to fill all ramifications
Ampules containing gutta-percha are heated for 15 •
minutes in the apparatus to plasticize the
.guttapercha
A short cannula with a diameter of 0.7 mm is •
.attached to each ampule