This document provides information on restoring endodontically treated teeth. It discusses the historical use of posts, objectives of restoration, changes to teeth after endodontic treatment, and factors to consider in treatment planning. Custom made posts involve preparing the tooth and canal, making a resin pattern of the canal, and casting a post and core. Proper ferrule effect, post length and diameter are important considerations.

2. RESTORATION OF
ENDODONTICALLY TREATED
TEETH

3. Chair person:
PROF. UMME KULSUM
Head of the department
Department of Conservative Dentistry and Endodontics
Dhaka Dental College
Supervised by:
DR. BEGUM ROKEYA AFSAR
Assistant professor
Department of Conservative Dentistry and Endodontics
Dhaka Dental College
Presented by:
DR.MD. REZAUL KARIM
MS (Resident), Orthodontics
Dhaka Dental College

4. CONTENTS:
 Introduction
 Historical perspective
 Objectives of final restoration
 Change of a tooth following endodontic treatment
 Evaluation of endodontically treated teeth
 Restorative treatment planning for endodontically treated
teeth
 Restorative options after endodontic treatment

5.  Restoration of teeth with minimal remaining tooth structures
Post & core
 Types of post and core
Factors to be considered while planning post and core
 Indications and contraindications of prefabricated
and custom made post and core
 Fabrication of custom made post and core
 Investing and casting Cementation
Conclusion

6. INTRODUCTION
Endodontic treatment is largely performed on
teeth which are significantly affected by caries,
multiple repeat restorations and /or fracture.
Already structurally weakened such teeth are
often further weakened by the endodontic
procedures to provide optimal access.
So for long term success skillful integration of both
endodontic and restorative procedure is
mandatory.

7. HISTORICAL PERSPECTIVE
• As early as 1728,Pierre Fauchard described
the use of “tenons” which were metal
posts screwed into the roots of teeth
to retain bridges.
• In the mid 1800, wood replaced metal
as the post material, and the “pivot crown”
a wooden post fitted to an artificial crown
and to the canal of the root, was popular
among the dentists. Often, these wooden
posts would absorb fluids and expand
frequently causing root fracture.

8. • It was later modified to eliminate the
threaded tube and was redesigned as a
one piece dowel and crown, which lost
its popularity quickly because they
were not practical.
During the 1930s,the custom cast post
and core was developed to replace the
one piece post crowns. This procedure
required casting a post and core as a
separate component from the crown.
This two step technique improved
marginal adaptation and allowed for
a variation in the path of insertion of
the crown.

9. • In 1869 ,Black introduced the metal posts in which a
porcelain faced crown was secured by a screw passing into
a gold lined root canal.
• Clarck in the mid 1800, developed a device that was
extremely practical for its time because it includes a tube
that allow drainage from the apical area of the canal.
• The Richmind crown was introduced in 1878, and
incorporated a threaded tube in the canal with screw
retained crown.

10. OBJECTIVES OF FINAL RESTORATION
 Maintain coronal and apical seal after
endodontic treatment.
 Protect and preserve the remaining tooth
structure.
 Provide a supportive retention ,foundation for
the placement of definitive restoration.
 Restore the function and aesthetics.

11. ARE ENDODONTICALLY TEETH ARE
DIFFERENT?

12. A) Architectural changes:
Increase susceptibility to fracture due to..
 Decay,
 Cutting of coronal tooth structure during access cavity
preparation
Access removal of redicular dentine during canal
preparation.

13. B) Change in the dentine physical
characteristics/moisture loss:
Effects of moisture loss are..
Dehydration
Loss of collagen intermolecular cross linking
Decrease in 14% strength and toughness of dentine

14. C) Esthetic changes:
Non vital teeth show loss of translucency and discolouration
and esthetics due to various reasons. Such as..
 Pulp necrosis
 Endodontic procedures
 Root canal filling materials
 Loss of tooth structures due to caries fracture
.

15. Are endodontically teeth are
more brittle?(Modern concept)

16. • Contrary to the common belief,
endodontically treated teeth are not more
brittle. In recent studies no difference in
moisture content was found between
endodontically treated teeth and a vital
tooth. It was found that vital dentine had
moisture content of 12.35% whilst dentine
from endodontically treated teeth had a
moisture content of 12.10%. (Papa J,et al
Moisture content of vital vs endodontically
treated teeth,)

17. The loss of vitality and a proper endodontically treated
teeth shows limited extent of changes of biomechanical
behavior. The tooth strength reduction is proportional
to coronal tissue loss by, carious lesion or restorative
procedure.

18. Evaluation of endodontically
treated teeth
A) Endodontic evaluation
B) Periodontal evaluation
C) Restorative evaluation
D) Esthetic evaluation

19. A) Endodontic evaluation
• Good apical seal.
• No tenderness on
percussion.
• No apical sensitivity.
• No exudate.
• No fistula.
• No active inflammation.
• Retreatement should be
done if there are signs and
symptoms including failure.

20. B) Periodontal evaluation
• Extent of underlying periodontal
disease.
• Adequate biological width.
• In case with extensive coronal
destruction crown lengthening can
be considered.
• Presence of enough coronal tooth
structure to incorporate ferrule into
cast restoration

21. C) Restorative evaluation
• Amount of remaining tooth
structure.
• Tooth type.
• Morphology of tooth.
• Occlusal and prosthetic
forces.
• Opposing dentition.

22. D) Esthetic consideration
• Thin gingiva may transmit a dark shadow of
the root through the tissue.

23. • Metal or dark carbon fiber placed in the canal can
result in unacceptable gingival discolouration from
the underlying root.

24. • Endodontic and restorative materials in these
esthetically critical cases must be selected so as to
provide the best health service with the minimum of
esthetic compromise.

25. Restorative Treatment Planning for
Endodontically Treated teeth

26. Following factors should be taken into
consideration.
A) Amount of tooth structure present
B) Occlusal forces and anatomic position of the tooth
C) Restorative requirements.
D) Morphology of root canal.

27. A) Amount of tooth structure present:
According to “Cohen” choice of post endodontic treatment
depends upon the amount of remaining tooth structure.
• Tooth with minimal loss of structure is inherently stronger and
can be restored with only coronal restoration.
• Tooth with >50% of remaining coronal structure can be restored
with crown.
• Tooth with 25-50% of remaining coronal structure can be
restore with non rigid post.
• Tooth with <25% of remaining coronal structure or <3-4 mm of
cervical tooth structure with rigid posts.

28. B) Occlusal forces and anatomic position of the
tooth:
• Anterior tooth with minimum loss of tooth structure can
be restored with coronal restoration. If the tooth is
discoloured, bleaching and veneer should be
considered. Anterior teeth with heavy horizontal forces
should be restored withstronger restorative component.

29. • Posterior tooth with considerable structure requires
restoration with onlay or crown to protect it against fracture.
In cases of extensive tooth damage, post/core followed by
crown is indicated.

30. C) Restorative requirement:
Teeth included as abutments in the fixed or partial
dentures undergo more forces and thus need
additional retention and protection against
fracture and caries due to leakage.

31. D) Esthetic requirement:
Loss of translucency and discolouration in the
endodontically treated teeth especially in
esthetic zone require restorative materials like
tooth coloured posts,composites and ceramic
cores and ceramic crown.

32. E) Morphology of root canal:
In case of structurally compromised teeth where
post and core are required ,canal shape ,canal
taper, curvature, angulation of canal with the floor
of the pulp chamber etc. also guide restoration
plan.

33. TREATMENT OPTIONS FOR
ENDODONTICALLY TREATED TOOTH

34. Anterior tooth
Minor coronal
damage
• Intact marginal
damage
• Intact incisal edge
• No colour change
• Esthetically
acceptable
Complete coverege is
not required
Conservative
treatment bonded
resin composite
Moderate coronal damage
• One or two large proximal
caries.
• Average size tooth
Full coverage crown is
required
Significant coronal damage
• Undermined marginal ridge
• Loss of incisal edge
• Coronal fracture or esthetically
unacceptable
Custom made or,
prefabricated post and core
Small circular canal
• Prefabricated post with resin
composite core followed by
full coverage crown
Extremely flared canal
• Custom made post and
core followed by a full
coverage crown

35. Posterior tooth
Minor coronal
damage
• Low risk of fracture
• Minimum occlusal
fracture
• Intact buccal and
lingual cusp
Conservative
treatment
• MOD only
• No post
Moderate coronal damage
Amalgam coronal and
radicular core or, resin
composite core followed by
full coverage crown
Significant coronal damage
Custom made or,
prefabricated post and core
Canal with circular in cross
section
• Prefabricated post with
amalgam or resin composite
core followed by full coverage
crown
Extremely tapered canal
• Custom made post and
core followed by a full
coverage crown

36. RESTORATION OF TOOTH WITH
MINIMUM REMAINING TOOTH
STRUCTURE

37. CHALLENGES
• These teeth have an increased risk of fracture.
• They provide decreased retention for restoration.
• That are in jeopardy for invasion of periodontal attachment.

38. As the remaining tooth structure decreases and
functional forces increased, greater restorative control is
needed. Extensively damaged or missing tooth structure
fundamentally alters the use of restorative procedures
and the need for adjunctive treatment.
In order to increase the resistance and support of the crown in
that case dowel core can be used.
A dowel core consists of two parts…..
1)Dowel/post
2) Core

39. Dowel core is of two types…
1. Prefabricated post and core
2.Custom made post and core

40. A dowel core provides the necessary amount of retention
and acts as a substitute for the lost tooth structure. But
studies have shown that the dowel does not take up any
masticatory load and that the dowel weaken the tooth
structure rather than strengthening it. Therefore dowel
preparation should be conservative

41. INDICATIONS FOR POST AND
CORE
• The remaining coronal tooth structure is inadequate for
the retention of a restoration.
• When there is sufficient root length to accommodate
the post while maintaining an adequate apical seal.

42. CONTRAINDICATIONS OF PLACING
POST
• Presence of signs of endodontic failures like poor apical seal,
active inflammation, presence of fistula or sinus and
tenderness on percussion.
• If adequate retention of core can be achieved by natural
undercuts of crown.
• If there are horizontal cracks in the coronal portion of the
teeth.
• When tooth is subjected to excursive occlusal stresses like
lateral stresses bruxism or heavy occlusal guidance

43. DOWEL/POST
It is a relatively rigid restorative material placed in the root of
nonvital teeth for retention of the core and to transmit forces from
core to the root.
Purpose of using post…
• It helps to retain the core.
• It helps to distribute the stresses through the radicular dentine to
the poor apex.

44. Earlier it was believed that post strengthens or reinforces the
tooth but it has been shown by various studies that posts actually
weakens the tooth and increase the risk of root fracture.
Therefore, a post should be used only when there is insufficient
tooth structure remaining to support the final restoration

45. IDEAL REQUIREMENT OF A POST
A post should..
• Provide maximum protection to the root to resist root
fracture.
• Provide maximum retention to the core and crown.
• Be easy to place.
• Be less technique sensitive

46. • Have high strength and fatigue
resistance.
• Be visible radio graphically.
• Be biocompatible.
• Be esthetic.
• Be easily available and not
expensive

47. CLASSIFICATION OF POSTS

50. CORE
Core is the supragingival portion that replaces the missing
coronal tooth structure and forms the centre of new restoration,
basically it acts as a miniature crown.
Ideal physical properties of core materials…
• Compressive strength to resist intracoronal forces
• Biocompatibility.
• Ease of manipulation.
• Flexural strength to prevent core dislodgement.

51. • Ability to bond to tooth structure and post.
• Coefficient of thermal expansion similar to dentine
• Minimal water absorption
• Dimensionally stable.
• No reaction with chemicals.
• Low cost.
• Easily available.
• Contrasting colour to tooth structure except when used
for anterior teeth.

52. Core build-up materials available
are
A) DIRECT PLACEMENT:
• Dental amalgam

53. • Glass ionomer
• Resin modified glass ionomer

54. •Composite resin

55. B) Indirect placement
• Custom made cast post and core

56. ESSENTIAL FACTORS TO BE
CONSIDERED DURING DOWEL CORE
PREPARATION
1) The canal should be obturated with guttapercha and not with
silver cone because, it is easy to remove. Removal of silver cones
can lead to lateral perforation.

57. 2) Post length:
• Greater the post length greater the retention.
• Ideal post length should be equal to the crown length or,
two third of the length of the root of involved tooth.
• Maintenance of 4-5 mm apical seal is required.

58. 3) Post diameter:
- The post diameter should not
exceed one third of the diameter of
the root.
- A minimum of 1mm sound
dentine should be maintained
circumferentially.

59. 4) Ferrule effect: Ferrule is a 360 degree metal collar of the
crown surrounding the parallel walls of the dentine extending
coronal to the shoulder of the preparation.
It has been seen that ferrule with 1-2 mm of vertical tooth
structure doubles the resistance to fracture than in teeth
without any ferrule effect.
Fig: Ferrule protections the integrity of
root by bracing action

60. Types of ferrule…
1)Core ferrule—Core ferrule is part of cast metal.
2)Crown ferrule—Crown ferrule is ferrule created by
overlying crown engaging the tooth structure.

61. 5) The restoration should not completely encroach
on the “Biological width”. A minimum of 4-5 mm of
supra bony tooth structure should be available to
accommodate for the restoration and attachment
apparatus.

62. Fabrication of custom made post
and core
The steps in the fabrication of post and core are..
A) Tooth preparation
B) Canal preparation
C) Canal pattern fabrication
D) Casting
E) Finishing and cementation

63. A) Tooth preparation:
• The tooth is prepared as usually.
• Unsupported enamel is removed.
• Only weak enamel is removed and it is not necessary to
remove all the coronal tooth structure.
• The tooth should be evaluated for residual caries to assess its
strength. Any weak enamel wall or restoration should be
removed.

64. B) Canal preparation:
• Pesso reamer is the instrument of choice for removing
gutta percha and for enlarging the canal because they have
non cutting tips, which follow the path of least resistance
(i.e. the reamer will try move along the length of the canal
instead of walls and perforating it)
• A hot condenser can be used to remove GP remnants.

65. • After removing the GP, the pesso reamer should again
be inserted to the require depth and used to enlarge
the canal.
• A test radiograph should be taken to decide the amount
of canal enlargement.

66. • The diameter of the canal should be at least 1/3rd of the
width of the tooth.
• A No. 170 bur is used to prepare a keyway in the tooth
along the length of the canal for a distance of 4mm.The
keyway should be equal to the width of the bur.
• A contrabevel is placed around the occlusal axial line
angle so that a metal coller is formed during casting which
will embrace the remaining coronal tooth structure and
protect it from fracture.

67. • The canal and the post are coated with petroleum
jelly.

68. C) Resin pattern fabrication:
• A 14 gauge plastic post is trimmed so that is slides easily
in and out of the canal.
• A notch is cut on the facial side of the post so that it can
be easily oriented.

69. • The external bevel(on the tooth) should be covered wit
resin before the resin in the canal is set.
• Next the canal is filled with fluid pattern resin.
• Now the plastic post should be inserted into the canal

70. • After the resin become doughy ,the pattern should be
pumped in and out so that it does not lock into any
undercut.
• Once the resin polymerizes , it should be removed from
the canal and inspected for voids.

71. • A second mix of acrylic is used for core build up.
• The core should be moulded with the hand to resemble a
prepared tooth.

72. • Green stone and garnet disks should be used to smoothen
and shape the coronal pattern.

73. D) Casting:
• The dowel core pattern should be wiped with alcohol to remove
all the lubricant.
• The pattern should be sprued at the cingulum.
• One to two cubic centimeter of extra water should be added to
the investment and a casting liner should not be used. So that
there is shrinkage of the dowel. A smaller dowel is preferred
because it will not bind to the canal.

74. • Burnout should be done for an additional 30mins to
ensure complete elimination of wax.

77. E) Finishing:
After casting , the sprue is cut off using a carbundum disk.
The dowel should be checked for proper fit.
If it binds to the canal, air abrasion should be done till the shiny
spots are removed.
The coronal portion should be polished to a statin finish using a
burlow wheel.
A groove should be cut along the length of the dowel from the
apical end to the contrabevel to act as escape way for the luting
cement.

78. F) Cementation:
• The luting agent must fill all dead space within the root canal
system. Voids may be a cause of periodontal inflammation via
lateral canals.
• The cement is loaded into the canal using lentulospiral.

79. • The post and core is inserted gently to reduce hydrostatic
pressure, which could cause root fracture.
• Final impression is made after cementation of the dowel and
the temporary crown is prepared.
• Permanent crown is cemented later.

81. CONCLUSION
• Although restoration of endodontically treated teeth has
been rationalized, information from controlled long term
clinical trials is still needed.
• As much tooth structure must be preserved as possible and
post and core is basically used to provide retention and
support for a cast restoration.
• There is not one post, core or final restoration that can be
used in all clinical situations. So we have to learn with these
variable and understand the basic concepts of how to use
them to maximum advantage.

82. BIBLIOGRAPHY
1. Textbook of endodontics;4th edition (Nisha Garg
and Amit Garg )
2. Grossman’s ENDODONTIC PRACTICE ;13th edition
3. Textbook of Prosthodontics; 2nd edition(Deepak
Nallaswamy Veeraiyan)
4. Also from different websites