The document discusses the monoblock obturation technique in root canal treatment, emphasizing the necessity for proper sealing and bonding to eliminate microbial presence effectively. It critiques gutta-percha as an obturation material, outlining its shortcomings like poor adhesion and limited robustness, while presenting advancements such as bioactive materials and resin-based systems. Ultimately, it highlights that current materials lack the necessary elastic properties for effective dental reinforcement and that successful monoblock configurations face challenges in achieving both strong bonding and sealing capabilities.

1. Monoblock
obturation
technique

2. successful root canal
treatment is based on:
Diagnosis and treatment planning
 knowledge of anatomy and
Morphology
 The traditional concepts of (CLEAN),
(SHAPE) , (FILL obturate ), and the
prober coronal restoration.
Introduction:

3. The shaped and cleaned
canal space represents an
environment in which
microbial communities
have been eliminated or
seriously disrupted and
can no longer promote
peri-radicular disease .

4. But how is this condition
preserved?
reliance on a coronal seal is probably
unacceptable without first filling the
canal system with materials that control
infection:
1.Directly: by actively killing
microorganisms which remain or
which gain later entry to the pulp
space

5. 2.Ecologically: by
denying nutrition, space
to multiply, and conditions
for the establishment of
significant biomass of microbes
They should do so long-term
and without damaging host
tissues.

7. Many materials have been used for
obturation Gutta percha is the most
successful one which has a number of
advantages include:
• Biocompatibility
• Flexibility of technique
• Thermoplastic
• Easily removed

8. Gutta-percha only satisfy the
secondary requirements of an ideal
obturating material RATHER THAN
which are not satisfied by gutta-percha.
The primary requirements of :
 Being an antimicrobial material

Sealing all the portals of exit in the
root canal system

9. Some other shortcomings of gutta-percha
 lack adhesive ability chemically bond
no bond to dentin, or any sealers
 Potential for voids, Lack rigidity , shrinks upon
cooling, approximately 5 to 7% , easily distorted
its inability to reinforce
endodontically treated tooth

10. For years endodontic sealers have been
considered the weak link in obturation
because
• they shrink the sealer tends to pull away
from GP
• solubility
• Some do not bond to dentin & and none
chemically to GP.
• Etc…
For this reason various compaction
techniques have been developed to help
minimize the sealer interface.

12. Monoblock concept

13. The literal meaning
of the word
monobloc is ‘Single
unit’.

14. The introduction
of the word ‘monobloc’
to dentistry can be traced
back to 1902, in the field
of orthodontics, by
Dr. Pierre Robin.

15. A monoblock obturation
system is the unit in which the
core material, sealing agent, and
the root canal dentin form a
single cohesive unit.
With the application of adhesive technology to
endodontics, the term MONOBLOCK has
become familiar

16. The monoblocks created in the root
canal spaces were classified as:
 primary
 secondary
 tertiary
Depending on the number of the interfaces
present between the
bonding substrate and the bulk core
material (Tay & Pashley 2007)

17. Primary Monoblocks
• A primary monoblock has only one interface that extends
circumferentially between the material and the root canal
wall.
• Examples-
 Hydron
MTA
BIO GUTTA
Polyethene fibre post-core build-ups
R C OBTURATING
MATERIAL
DENTIN

18. Secondary Monoblocks
 Secondary monoblocks are those that have two
circumferential interfaces, one between the sealer and
primed dentine and the other between the sealer and the
core material
 Examples-
Resilon
Propoint (C Point)/hyseal bio
Prefabricated post systems
bonded to root canal dentin via resin cements
CORE
SEALER
DENTIN

19. Tertiary monoblocks
 are those that have 3 circumferential interfaces
1. one between the sealer and primed dentine
2. second interface between the sealer and the coating that have
been applied over the non-bondable gutta-percha points to
make them bondable to the root canal sealers
3. third between coating and core material

20. Examples-
• EndoREZ - coating gutta-percha cones with a
polybutadiene-diisocyanate-methacrylate adhesive.
• ActiV GP- conventional gutta-percha cones that are
surface coated with glass ionomer fillers using a
proprietary technique
CORE
COATING
SEALER
DENTIN

23. There are two prerequisites
for the monoblock to function as a
mechanically homogeneous unit:
• First, the materials that constitute the
monoblock should have the ability to
bond strongly and mutually to each
other, as well as to the substrate that
the monoblock is intended to
reinforce.

24. Purported reasons for microgaps and subsequent
leakage between GP and sealer include:
• poor adhesion and wetting,
• polymerization shrinkage,
• thermal stresses
• occlusal loading
• water sorption.
increased efforts have been directed
towards the development of
bonded obturating materials.
Sealability

25. Teeth with significant loss of
structure require posts in the
interest of retaining the core.
Since the currently favored
fibre posts are passively
retained into the root canal, an
adhesive cement is important
for a good seal.
Sealability

26. • Second ,
Monoblock materials should
have a modulus of elasticity
that is similar to that of the
substrate , that the
monoblock is intended to
reinforce. (dentin) &
restoration ????
•

27. Teeth which are root canal filled are
prone to biomechanical failure due to:
loss of tooth structure and integrity
+
masticatory forces
fatigue stress.
MOE OF DENTIN (i.e 14.0–18.6
GPa)

28. Methacrylate resin
• hydrophilic properties,
which enable them to wet the canal walls and
penetrate dentinal tubules.
• bondability to the radicular dentin
and root canal materials is also superior compared to
other cements.
Four generations have been introduced.

29. 1-The first generation;
contained poly [2-hydroxyethylmethacrylate] HEMA as major
ingredient was marketed as Hydron.
2-The second generation:
are hydrophilic and does not require etching to the adjunctive use of
a dentin adhesive Eg; ENDOREZ.
3-The third generation :
involve the use of a self-etching primer and dual-cured resin
composite Sealer Eg; RESILON/EPIPHANY.
4-The fourth generation sealers:
where in the etchant, primer and sealer were incorporated into an
all-in-one self-etching, self-adhesive sealer Eg; METASEAL.

30. Teeth with significant loss of structure require
posts for retaining the core. Since fibre posts
are passively retained into the root canal, an
adhesive cement is important for a good seal.
These cements may be
categorized as;
 Total-Etch Resin Cements,
Self-Etch Resin Cements
Self-Adhesive Resin Cements.

31. Hydron (Hydron technologies,Inc.
Pompano Beach, FL, USA)
 is is an example of a primary monoblock .
 Used to fill the root canals extensively in the late
1970s.
 it demonstrated ease of application , no core
injectable

It consists of 2-hydroxy ethyl methacrylate
(HEMA).

33. it was not stiff enough to strengthen
the canal surfaces.

poor antibacterial properties.
Poor adaptability to the canal wall.
advers inflammatory reactions .
 leakage issues were also observed.

34. MTA (Mineral Trioxide Aggregate)

35. In 1993 Torabinejad introduced MTA, a calcium-based
material,
MTA is composed principally of
Portland cement 75%
GYPSUM 5%
with the addition of bismuth
trioxide 20% to render it
radiopaque.
The main reaction between the tricalcium and
dicalcium silicate and water resulted in the
production of calcium silicate hydrate gel, which
is poorly crystalline, and calcium hydroxide

36. Compounds
• Tricalcium Silicate (C3S)
• Dicalcium Silicate (C2S)
• Tricalcium Aluminate (C3A)
• Tetracalcium Aluminoferrite
(C4AF)

37. Advantages
•
Compatible and stimulates mineralization
•
Antimicrobial
•
Forms hydroxyapatite on the surface and
provides a biological seal Bioactive; i.e., it
encourages differentiation and migration of
hard tissue producing cells
•
Exhibits high adhesiveness to dentin as
compared to other conventional sealers

38. • Sealing ability is similar to that of epoxy resin–
based sealers
•
Forms calcium hydroxide that releases calcium
ions
•
Nontoxic and nonmutagenic
•
Provides effective seal against dentin and
cementum and promotes biological
• repair and regeneration of the periodontal
ligament

39. • Disadvantages
•
Can cause discoloration due to the release of
the ferrous ions
•
Long setting time
•
Short working time of less than 4 minutes
•
Inadequate compressive strength
•
Improper handling characteristics
•
No known solvent is available

40. Bioactive gutta-percha
(Bio-Gutta Smartodon Smartodont
llc Zurich - Switzerland)
All-in-one root filling material that
forms a true monoblock in the root
canal system without any sealer.

41. • contains bioactive glass incorporated into
polyisoprene.
• The material is self-adhesive with immediate
sealing of the canal system through formation
of Calcium Phosphate crystals on the
material’s surface in a wet environment.
• studies report good push out bond strength to
the canal dentin when compared with
conventional gutta percha.
(Bio-Gutta Smartodon Smartodont llc
Zurich - Switzerland)

42. Polyethylene fibre post-core
systems
(Ribbond Inc., Seattle, WA,USA)
made of ultra-high
molecular weight
polyethylene fibers
(UHMWP)

45. Resilon™*
Material is a thermoplastic synthetic
polymers of polyester
polycaprolactone polymer
root canal filling material.
Resilon Material contains also:
• bioactive glass
• radiopaque fillers

46. Resilon Core material:-
Organic part: thermoplastic synthetic polymer –
Polycaprolactone (50%) .• Methacrylate co-
polymer(10%)helps in bonding chemically
with methacrylate based sealers,
Inorganic part: bioactive glass, bismuth oxychloride,
barium sulphate(40%)•

47. Resilon Sealer:-
Organic part: BisGMA, ethoxylated BisGMA, UDMA,
hydrophilic
difunctional methacrylates
Inorganic part: calcium hydroxide, barium sulphate, barium
glass,
bismuth oxychloride, silica ~70%
Resilon Primer:-
sulfonic acid terminated functional monomer, HEMA, water,
polymerization initiator

48. PROPERTIES :
• CYTOTOXICITY : Resilon is same as
biocompatible as G.P.
• MELTING POINT : 60.50 C.
• REMOVAL FOR RETREATMENT : heat or
solvents like chloroform can be used for removal
of the resilon points.
• REINFORCEMENT OF TOOTH STRUCTURE : it
can provide 20% more that of the G.P points
provide.
• Resilon has low melting point than G.P
• Resilon has higher molecular weight that G.P

49. Resilon Delivery System

50. MetaSEAL® Endodontic Sealer
Figure 1
In this micrograph of a cross-sectioned
point, you can see where MetaSEAL
penetrated the gutta percha to create a
hybrid bond. The strength of this bond
actually exceeds the cohesive strength of
the point.

51. Advantages of Resilon are:
• Decreased incidence of root fracture
• Better radiopacity than gutta-percha
• Dual cure capabilities for immediate
coronal seal, Elimination or considerable
reduction in microbial leakage
• Less irritation than epoxy or ZOE
sealers

52. Modulus of elasticity of dentin – 16000 Mpa
Material to reinforce dentin Should have the same
elasticity Modulus of elasticity – G.P – 74.22 Mpa,
Resilon – 129.16
Franklin Tay et al (2006):Weak chemical
union between resilon and methacrylate
sealerCause – Phase separation due to
insufficient dimethacrylate inresilon and
absence of free radicals within resilon for
coupling alternative
Is Resilon the Solution?

53. Dr Franklin Tay
• recognized the presence of the
configuration factor or C-factor that is seen
in bonded restorations in cavities and
concluded that the high C-factors in root
canals impose challenges in creating
endodontic monoblocks.
• His research on polymer constituents
of Resilon has shown degradation by
bacterial and salivary enzymes.

54. METHOD OF USE :• After the canal preparation is
done, irrigation is done with 5.25% sodium hypo
chloride solution and final rinse is done with 17%
EDTA• Canal is dried with the paper points.• Self-
etch primer is brought into the canal by insertion
of a saturated fitted paper point.• Excess is
removed with a dry paper point.• Epiphany resin
sealer is then express into the canal using a auto
mix syringe.• The fitted master cone was coated
with the sealer and is placed into the canal.•
Obturation is completed using Downpack and
Back fill technique.

55. The C Point
(EndoTechnologies, LLC,
Shrewsbury, MA, USA)

56. Fibre posts

57. EndoreEndoREZ® -
Ultradentz

58. Activ GP Precision Obturation System
(single cone technique) (Endosequence
and Brasseler USA)

59. Brasseler bioceramic sealer

60. Fiber posts that contain
an external silicate coating or
nonpolymerized resin
( anatomic posts)

62. and fibre posts that contain an
extra silicon coating such as
• DT Light (VDW GmbH, Munich,
German)
ceramic posts that require a silane
coating such as
• Cosmopost (Ivoclar, Vivadent, AG,
Schaan, Liechtenstein)
can be considered as tertiary
monoblocks

64. CONCLUSION
First and foremost currently available resin
based root canal filling available have a
modulus of elasticity far less compared to
dentin.Under these circumstances it seems
highly unlikely that these materials contribute
towards root reinforcement.

65. • Secondly the idea of monobloc is built on the
assumption that improved bonding within
the canals would lead to good sealing.Yet it
has already been proven that the good bond
strengths of adhesive materials may not
imply or equate with good sealing ability.
Resin based products problems.
• Finally while designing a single unit root filling
forms the cornerstone in achieving the
‘monobloc effect’ all root filling materials
used today require additional interfaces.