DANYLO HALYTSKY
NATIONAL MEDICAL UNIVERSITY OF LVIV
DEPARTMENT OF THERAPEUTIC DENTISTRY
METHODOLOGICAL GUIDE
for practical classes
„Preclinical course of Therapeutic Dentistry”
(IV semester)
for the 2-nd year students
Part II
Lviv-2012
1
The methodological guide worked out by: M. Hysyk,
O. Ripetska, Yu. Riznyk
Edited by prof. V. Zubachyk
Accountable for an issue  first vice-rector of
scientific and academicl work, professor, Corresponding
Member of the Academy of Medical Sciences of Ukraine, M.R.
Gzhegotskiy.
Reviewers: associate professor of department of
Surgical dentistry N. Krupnik,
associate professor of department of
Pediatric dentistry N. Chukhraj
Methodological guide for students in Therapeutic
dentistry (III semester) was discussed and approved on the
sitting of the department of Therapeutic dentistry (record of
proceedings №15, dated from 11, May, 2010) and approved on
the meeting of Methodological committee in dentistry
disciplines on June 22, 2010, protocol № 3.
Computer printing: Oksana Zamoiyska
2
CONTENT OF THE COURSE
Page
1.
2.
3.
4.
5.
6.
7.
8.
Practical
lesson
33.
Endodontics.
Topographical anatomy of permanent teeth
cavities and root canals …………………………
Practical lesson 34. Technique of tooth cavity
opening. Medications for pulp devitalization.
Local anesthesia ………………………………..
Practical lesson 35. Endodontic instruments.
Classification. Types. Indications for use ………
Practical lesson 36. Work with endodontic
instruments. The use of medications for cleaning
of the root canal. Methods of cleaning and
widening of root canals …………………………
Practical lesson 37. Root canal filling materials.
Classification.
Main
demands.
Partially
hardening sillers. Composition. Characteristic.
Indications for use ……………………………...
Practical lesson 38. Filling of the root canals
with partially hardening and hardening sealers
and fillers ……………………………………….
Practical lesson 39. Methods of fillings of the
root canals. Mistakes and complications during
endodontic manipulations, their reasons and
ways of removal ………………………………..
Practical lesson 40. Summary control 2 ……..
3
4
26
33
42
49
61
67
75
Practical lesson No 33
Theme: Endodontics. Topographical anatomy of permanent
teeth cavities and root canals.
Short description of a theme
The endodont complex connects dentin, pulp, apical
periodont, cement of the apical part of the root and a bone. The
effectiveness of the root canal system treatment depends on the
pulp chamber anatomy and a root canal system morphology.
The pulp chamber is similar to the crown morphology.
Pic.1. The root canal systems
The 4 canal types:
- the teeth, which have 1 root canal from orifice to apex
opening
- the teeth have 2 root canals which are connected near
the root apex and have 1 apex opening
- the teeth which have two roots, and have 2 apexes
opening
- the teeth which have 1 root canal and are divided in the
root apical part on part and have 2 apex opening
Central upper incisors
On the mesiodistal cut in central incisors, the pulp
chamber is broad and may have a suggestion of mesial and
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distal horns. On the labiolingual cut the pulp chamber tapers to
a point toward the incisal edge. Often central incisors root have
a bend in apical area, as usual in palatal direction.
Medium length of the tooth is 22,5 mm
The number of roots is most frequently one.
Central incisor usually has 1 canal (type I)
Lateral canals – seldom
Apical delts – often
Apical opening localization
- 0-1 mm from the root apex - 80%
- 1-2 mm from the root apex - 20%
Pic.2. Central upper incisors
Lateral upper incisor
In the neck area the canal is wider in vestibule-oral
direction. On the mesiodistal cut in lateral incisors, the pulp
chamber is broad and may have a suggestion of mesial and
distal horns. On the labiolingual cut the pulp chamber tapers to
a point toward the incisal edge. The roof of the pulp chamber is
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often rounded. Often lateral incisors roots have a bend in apical
area, as usual in palatal direction.
Medium length of the tooth is 22 mm
The number of roots is most frequently 1 – 99,9%
Amount of canals
1 – 99,9%
Lateral canals
– seldom
Apical delts
– often
Apical opening localization - 0-1 mm from the root apex - 90%
- 1-2 mm from the root apex - 10%
Pic. 3. Lateral upper incisor
Upper canine
The pulp cavity is large. The incisal wall or roof of the
pulp chamber is often rounded. The upper canine pulp chamber
is similar to the crown. Root canal is straight. Often upper
canine roots have a bend in apical area, as usual in palatal or
distal direction.
Medium length of the tooth is 26,5 mm
The number of roots is most frequently 1 – 99,9%
6
Amount of canals
1 – 99,9%
Lateral canals
– seldom
Apical delts
– seldom
Apical opening localization - 0-1 mm from the root apex - 70%
- 1-2 mm from the root apex - 30%
Pic. 4. Upper canine
1-st upper premolar
On the mesiodistally at the occlusal border of roof is
curved beneath the cusp similar to the curvature of the occlusal
surface. Pulp chamber is prolong in vestibulooral direction.
The buccal canal orifice is located just lingual to the buccal
cusp tip. The lingual canal is located just lingual to the central
fossa. Most of the 1-st upper premolars are concave on mesial
root surface. On buccolinguale cut the pulp horns in the roof
are visible beneath each cusp. The buccal horn is longer than
the lingual horn. The pulp chamber often has general outline of
the tooth surface, sometimes including a constriction near or
apical to the cervix. The average incidence of two canals,
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buccal and lingual, is 90% (both Type I when two roots are
present, and either a Type II or Type III with one root).
Medium length of the tooth is 20,6 mm
The number of roots
1 – 19%, 2 – 80%, 3 – 1%
Amount of canals
1 – 4%, 2 - 95%, 3 – 1%
Lateral canals
– seldom
Apical delts
– seldom
Apical opening localization - 0-1 mm from the root apex - 95%
- 1-2 mm from the root apex - 5%
Pic. 5. 1-st upper premolar
2-nd upper premolar
Medium length of the tooth is 21,5 mm
The number of roots
1 – 90%, 2 – 9%, 3 – 1%
Amount of canals
1 – 75%, 2 - 24%, 3 – 1%
Lateral canals
– seldom
Apical delts
– seldom
Apical opening localization - 0-1 mm from the root apex - 75%
- 1-2 mm from the root apex - 25%
When there is one canal, the orifice is located in the
exact center of the tooth. If the orifice is located toward the
buccal or the lingual, it probably means there are two canals in
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the root. The average incidence of two canals is about 24%
(Type II or Type III) .
In 10-15% cases on 3-4 mm from root apex the basic
root canal may be divided into on two canals. Often, near the
apical opening two canals can be connected, but in this case
most often it there are two apical openings.
Pic. 6. 2-nd upper premolar
1-st upper molar
Pulp Chamber.
There is a pulp horn well beneath each cusp in the roof
of the chamber. The pulp chamber is normally deep to or some
distance from the occlusal surface. One exception might be the
pulp horn of the mesiolingual cusp. The pulp chamber is
broader buccolingually than mesiodistally and is often
constricted near the floor of the chamber. The floor of the pulp
chamber is constricted apically to the cervical line; it is located
in the root trunk. It has three or four openings, one for each
root canal. Most frequently three are roots, but four canals;
one for each in the distobuccal and palatal root: two in the
mesiobuccal root. In the palatal root, the canal is larger and
more easily accessible from the floor of the pulp chamber than
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for the other two roots, but this root and its canal often bend
toward the buccal in the apical third.
The palatal orifice is located beneath the mesiolingual
cusp. The distobuccal orifice is located on a line between the
palatal orifice and the buccal developmental groove at a point
just short of the angle formed by the buccal and distal walls of
the pulp chamber. The mesiodistal orifice is located slightly
mesially to and beneath the mesiobuccal cusp tip. The MB2
orifice is located 2-3 mm distal and slightly to the palatal
aspect of the mesiobuccal orifice.
Medium length of the tooth is 20,8 mm
The number of roots
2 – 15%, 3 – 85%
Amount of canals
3 – 60%, 4- 40%
Lateral canals
– sometimes
Apical delts
– seldom
Pic. 7. 1-st upper molar
2-nd upper molar
Pulp Chamber.
There is a pulp horn well beneath each cusp in the roof
of the chamber. The pulp chamber is normally deep to or some
10
distance from the occlusal surface. One exception might be the
pulp horn of the mesiolingual cusp. The pulp chamber is
broader buccolingually than mesiodistally and is often
constricted near the floor of the chamber. The floor of the pulp
chamber is constricted apically to the cervical line; it is located
in the root trunk. It has three or four openings, one for each
root canal. Most frequently have there are roots, but sometimes
four canals; one for each in the distobuccal and palatal root:
two in the mesiobuccal root. In the palatal root, the canal is
larger and more easily accessible from the floor of the pulp
chamber than for the other two roots, but this root and its canal
often bend toward the buccal in the apical third.
The location of the orifices in the maxillary second
molar is similar to the maxillary first molar, except that they
are closer together.
Medium length of the tooth is 20mm
The number of roots
1-1%, 2 – 19%, 3 – 80%
Amount of canals
1-1%, 2 – 2%, 3 – 57%, 4- 40%
Lateral canals
– sometimes
Apical delts
– seldom
Pic. 8. 2-nd upper molar
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First lower incisor
On the mesiodistal cut in central incisors, the pulp
chamber is broad and may have a suggestion of mesial and
distal horns. On the labiolingual cut the pulp chamber tapers to
a point toward the incisal edge.
In 60% the lower central incisor canal has - I type, 35% - II
type, 5% - III type
Medium length of the tooth is 20,7 mm
The number of roots is most frequently one.
Central incisor has 1 canal (60%), 2 canals (40%)
Lateral canals – seldom
Apical delts – seldom
Apical opening localization - 0-1 mm from the root apex - 90%
- 1-2 mm from the root apex - 10%
Pic. 9. First lower incisor
Second lower incisor
On the mesiodistal cut in central incisors, the pulp
chamber is broad and may have a suggestion of mesial and
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distal horns. On the labiolingual cut the pulp chamber tapers to
a point toward the incisal edge.
Medium length of the tooth is 21,7 mm
The number of roots is most frequently one.
Central incisor has1 canal (60%), 2 canals (40%, usually Type
II)
Lateral canals – seldom
Apical delts – seldom
Apical opening localization - 0-1 mm from the root apex - 90%
- 1-2 mm from the root apex - 10%
Pic. 10. Second lower incisor
Lower canine
Tha pulp cavity is large. The incisal wall or roof of the
pulp chamber is often rounded. The lower canine pulp chamber
is similar to the crown. Root canal is straight. Often lower
canine has a bend in apical area, as usual in distal direction
Medium length of the tooth is 25,6 mm
The number of roots
1 (98%), 2 (2%)
The number of canals
1 (94%), 2 (6%)
13
Lateral canals – seldom
Apical delts
– seldom
Apical opening localization - 0-1 mm from the root apex - 95%
- 1-2 mm from the root apex - 5%
Pic. 11. Lower canine
First lower premolar
The occlusial border or roof is curved beneath the cusp
similar to the curvature of the occlusal surface. On
buccolingual cut the pulp horns in the roof are visible beneath
each cusp. The buccal horn is longer than lingual horn. The
pulp chamber often has the general outline of the tooth surface,
sometimes including a constriction near or apically to the
cervix. First premolar most frequently has one root and one
canal. The first premolar has a Type I canal system about 70%
of the time and Type IV canal system 24% of the time. The
canal orifice is located just buccal to the central fossa.
Medium length of the tooth is 25,6 mm
The number of roots
1 (98%), 2 (2%)
The number of canals
1 (94%), 2 (6%)
Lateral canals – seldom
14
Apical delts
– seldom
Apical opening localization - 0-1 mm from the root apex - 95%
- 1-2 mm from the root apex - 5%
Pic.12. First lower premolar
Second lower premolar
The occlusial border or roof is curved beneath the cusp
similar to the curvature of the occlusal surface. On
buccolingual cut the pulp horns in the roof are visible beneath
each cusp. The buccal horn is longer than lingual horn. The
pulp chamber often has the general outline of the tooth surface,
sometimes including a constriction near or apically to the
cervix.
The second premolar has one root canal 96% of the
time and a Type IV system 2,5% of the time. The canal orifice
is located just buccally to the central fossa.
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Medium length of the tooth is 25,5 mm
The number of roots
1 (100%)
The number of canals
1 (89%), 2(10%), 3(1%)
Lateral canals – seldom
Apical delts – seldom
Apical opening localization - 0-1 mm from the root apex - 65%
- 1-2 mm from the root apex - 30%
- 2-3 mm from the root apex - 5%
Pic. 13. Second lower premolar
First lower molar
There is a pulp horn well beneath each cusp in the roof
of the chamber. The pulp chamber is normally deep to or some
distance from the occlusal surface. The floor of the pulp
chamber is constricted apically to the cervical line; it is located
in the root trunk. It has three or four openings, one for each
root canal.
Most frequently there are two roots (mesial and distal),
and three canals (one in the distal root and two in the mesial
root). The mesial root usually has two canals: mesiobuccal and
16
mesiolingual. A Type III canal system is present 60% of the
time and Type II canal system is present 40% of the time. The
mesiobuccal orifice is located slightly mesial and close to the
mesiobuccal cusp tip. The mesiolingual orifice is just lingual to
the mesial developmental groove of the mesial marginal ridge.
It is not under the mesiolingual cusp tip, but is in a more
central location.
In the distal root, the canal is larger and more easily
accessible from the floor of the pulp chamber than for the other
root. The distal root has two canals approximately 35% of the
time. If the distal root has one canal, the orifice is larger and
located just distal to the center of the crown. When two canals
are present, the distolingual orifice is smaller and is located
centrally just lingual to the central fossa. Usually the canal
configuration is Type II system.
Medium length of the tooth is
21 mm
The number of roots
2 – 98%, 3 – 2%
Amount of canal
3 – 80%, 4- 7%, 2 -13%
Lateral canals – sometimes in furcation region
Apical delts – seldom
Pic. 14. First lower molar
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Second lower molar
Pulp Chamber.
There is a pulp horn well beneath each cusp in the roof
of the chamber. The pulp chamber is normally deep to or some
distance from the occlusal surface. The floor of the pulp
chamber is constricted apically to the cervical line; it is located
in the root trunk. It has three or four openings, one for each
root canal. Most frequently there are two roots (mesial and
distal), and three canals (one in the distal root and two in the
mesial root). In the distal root, the canal is larger and more
easily accessible from the floor of the pulp chamber than for
the other root.
A Type II canal system is present 38% of the time and a
type III canal system is present 26% of the time. The location
of the orifices for mandibular second molars is similar to that
of the mandibular first molars.
Medium length of the tooth is 20 mm
The number of roots
2 – 84%, 3 – 1%, 1-15%
Amount of canals
3 – 77%, 4- 7%, 2 -13%, 1-3%
Lateral canals – sometimes in furcation region
Apical delts – seldom
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Pic. 15. Second lower molar
Third molars
Maxillary and mandibular third molars are very
considerable in form, having from one to seven cusps. Third
molars will have as many pulp horns as cusps, and as many
root canals as roots. Maxillary third molars usually have three
root canals and mandibular molars usually have two.
Pic. 16. Third upper molar
19
Pic. 17. Third lower molar
Control questions to practical lesson
1. How many roots and canals are there in the central upper
incisor?
2. How many roots and canals are there in the lateral upper
incisor?
3. How many roots and canals are there in the upper canine?
4. How many roots and canals are there in the 1-st upper
premolar?
5. How many roots and canals are there in the 2-nd upper
incisor?
6. How many roots and canals are there in the 1-st upper
molar?
7. How many roots and canals are there in the 2-nd upper
molar?
8. How many roots and canals are there in the 3-d upper
molar?
9. How many roots and canals have the central lower incisor?
10. How many roots and canals are there in the lateral lower
incisor?
11. How many roots and canals are there in the lower canine?
12. How many roots and canals are there in the 1-st lower
premolar?
13. How many roots and canals are there in the 2-nd lower
premolar?
20
14. How many roots and canals are there in the 1-st lower
molar?
15. How many roots and canals are there in the 2-nd lower
molar?
16. How many roots and canals are there in the 3-d lower
molar?
Situation tasks and test control
1. What elements does the „tooth cavity” include?
A. Pulp chamber, root canal system
B. Pulp chamber, basic root canal, additional root canals, apex
C. Pulp chamber, basic root canal, additional root canals, apical
delta, apex
D. Pulp chamber
2. What elements does the pulp-dentinal complex consist of?
A. Odontoblasts, predentin, dentin
B. Odontoblasts, predentin, dentin, vessels, nerves
C. Odontoblasts, predentin, dentin, vessels, nerves, pure cells
layer, rich cells layer
D. Odontoblasts, predentin, dentin, vessels, nerves, pure cells
layer, rich cells layer, central layer
3. What formations contain the epithelial cells?
A. Pulp-dentin complex
B. Pulp-periapical complex
C. Pulp
D. No one
4. What formations does the „endodont” clinical definition
include?
A. Pulp-dentin complex
21
B. Pulp-periapical complex
C. Pulp
D. Any
5. What classes according Black classification are the most rare
that cause the pulp inflammation?
A. I
B. II
C. III
D. IV
E. V
6. What elements does the root canal system consist of?
A. Basic canal
B. Second basic canal in the same root
C. Additional canals
D. Аpical deltas
E. Transversal canals
7. How often the apical opening does not coincide with the
tooth root apex? Name the percentage.
A. 25%
B. 50%
C. 75%
D. 100%
8. What is the mean distance from the anatomical to the tooth
root apex?
A. 0 mm
B. 0, 5 mm
C. 1 mm
D. 1, 5 mm
E. 2 mm
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9. What is the time of the apex of the root maturation?
A. 0,5 year
B. 1 year
C. 2 years
D. 3 years
10. What are the age changes in tooth and tooth root canal
system?
A. Tooth cavity decrease, abrasion, tooth mobility
B. Tooth cavity decrease, secondary dentin and cement
formation (deposition), alveolar process atrophy
C. Tooth cavity decrease, secondary dentin and cement
formation (deposition), alveolar process atrophy, tooth mobility
11. Name the percentage of cases when 4 canals in the 1-st
lower molar can be observed?
A. 5%
B. 10%
C. 20%
D. 30%
12. The cell activity is temporarily suspended in the external
pulp area. What tooth tissue possesses the menace of
physiological regeneration deficit?
A. Dentin
B. Cement with cells
C. Cement without cells
D. Enamel
E. Pulp
13. The examination of a patient revealed the insufficient tooth
pulp development. What embryonal source was damaged?
A. Endoderm
B. Epithelium of the mouth
23
C. Mesenchyma
E. Ectoderm
14. A healthy dental pulp responses to the damage:
A. By effective collateral blood circulation for transporting the
inflammatory elements to the affected site
B. By deposition of highly mineralized and tubular restorative
dentin
C. By development of the inflammatory reaction with the
following partial or complete pulp necrosis
D. By formation of the reparative dentin on the pulp surface
under the foci of irritation
15. Fibroblasts:
A. The smallest amount of cells in the pulp
B. The cells producing collagen fibers
C. The cells whose amount increases simultaneously with the
increase of blood vessels, nerves and fibers
D. The cells which are subjected to active differentiation in the
pulp
16. Capillaries are found throughout the entire pulp, but the
majority of them is in:
A. Pulp cusps
B. Central pulp
C. Subodontoblastic layer
D. In the root region
17. Root canal obliteration:
A. Usually the prognosis as to the tooth saving in not
comforting
B. Can be removed with a drill
C. In most cases it happens in patients with pathology of
development
24
D. It may need a complex special measures in treatment
18. The sharp root canal narrowing on the X-ray film usually
means:
A. Root canal obliteration
B. Branching or separating of the root canal
C. Artefact on the X-ray
D. Dystrophic calcification
Reference literature
1. Clincal endodontics: a textbook /Leif Tronstad.– 3rd rev.
ed.– New Yourk, 2009.– 249 p.
2. Stephen Cohen, Richard C. Burns. Pathways of the pulp.
Eighth edition.– Mosby, 2002.– 1031 p.
3. Fan B, Wu M-K, Wesselink PR. Leakage along warm
gutta-percha fillings in the apical canals of curved roots.
Endod Dent Traumatol 2000;16:29-33.
4. Glosson CR, Haller RH, Brent Dove S, del Rio CE.
Comparison of root canal preparations using NiTihand,
NiTi engine-driven and K-flex endodontic instruments. J
Endod 1995;21:146-51.
5. Molven O, Halse A, Grung B. Surgical management of
endodontic failures: indications and treatment results. Int
Dent J 1991;41:33-42.
6. Seltzer and Bender’s. Dental pulp // Quintessence
Publishing, 2002.
25
Practical lesson No 34
Theme: Technique of tooth cavity opening. Medications for
pulp devitalization. Local anesthesia.
Short description of a theme
Access cavity preparation.
Access to the pulp chamber and canal system is
achieved through the use of rotary high-speed burs in a dental
handpiece to bore an opening in the affected tooth, typically on
the lingual surface of anterior teeth and the occlusal surface of
posterior teeth. A variety of bur types can be used depending
on the preference of the operator and the status of the clinical
crown. Long-shanked tungsten-carbide burs and size 2, 4, or 6
round burs can be used to make the access cavity. After the
pulp chamber is located with a sharp, stainless steel endodontic
explorer, safe-ended diamond burs or Endo-Z (Dentsply) burs
are used to unroof the chamber and refine the axial walls of the
cavity preparation. Enhanced illumination and magnification
with head lamps, loupes, or a surgical operating endodontic microscope, with magnifications up to 26 X, can aid the clinician
in locating calcified canals and identifying fractures.
Removal of roof. The first step is to locate and remove
the entire roof of the pulp chamber so that its walls are
continuous with the access cavity. Any pulpal remnants left in
the pulp chamber will break down and cause the crown of the
tooth to discolour. In addition during preparation of the canal
the debris left in the pulp chamber may be pushed down the
canal by instruments and cause infection. Direct line access.
The shape of the access cavity should be cut so that the coronal
walls do not deflect instruments during root canal preparation.
26
Access should be in a direct line with the apical third of the
root canal.
Particular care must be taken not to damage the floor of
the pulp chamber. In the case the floor of the pulp chamber in
the molar is flattened with a bur, the location of the canal
orifices will be much more difficult. The natural floor tends to
guide an instrument into the canal orifice. The floor of the pulp
chamber in the mandibular molar for example has the hump in
the centre of the floor which will deflect the point of an
instrument.
Conserve tooth substance. The access should not be
made so large that the walls of the tooth will be unnecessarily
weakened. The tooth must be capable of being restored.
Cutting the access cavity may be divided into three
stages -locating the pulp chamber with a bur, secondly
removing the roof of the pulp chamber, and finally completing
the shape of the cavity.
Stage 1. A tapered tungsten 701 friction grip bur is used
to locate the pulp chamber. In anterior and premolar teeth the
bur is held in the main axis of the tooth. If the preoperative
radiograph shows a fine canal this stage is carried out before
the rubber dam is placed so that the orientation of the tooth is
not lost.
In posterior teeth the handpiece head and bur are held in
front of the preoperative radiograph which has been taken with
a paralleling technique. The depth and angle of penetration
from the occlusal surface may be estimated.
The initial penetration in posterior teeth is directed
towards the main axis of the largest canal, that is the palatal
canal in the maxillary teeth and the distal canal in the
mandibular teeth. The pulp chamber will be at its widest in this
area.
Stage 2. A No. 6 round bur in a slow handpiece is used
to remove the pulp cornua and remainder of the roof of the
27
pulp chamber. The bur is placed in the pulp chamber and a
cutting action used only on the withdrawal stroke so that the
roof is lifted off the chamber.
Stage 3. The access cavity shape is completed using a
non-end cutting, tapered, diamond friction grip bur. It is
important to ensure that the walls of the pulp chamber are
continuous with the walls of the access cavity and that the
cavity is bevelled to provide resistance form for the temporary
restoration.
Control questions to practical lesson
1.
2.
3.
4.
5.
6.
What instruments are used for tooth cavity opening?
What are the steps of the tooth cavity opening?
How the roof of the pulp chamber is removed?
What are the demands for the access cavity shape?
Enumerate medications for pulp devitalization?
Discribe the way of placement of pulp devitalization
agents.
Situation tasks and test control
1. Localization of the access cavity on the occlusial surface
concerning another surface:
A. А
B. В
C. С
2. Root canal orifice should be localized with help of:
A. Condenser with a small working part
B. Endodontic File No15
C. Small ball round-shaped drill
28
D. Endodontic probe
3. The most frequent clinical mistake in the lower incisor pulp
chamber opening is:
A. Lingual perforation
B. Labial perforation
C. Incisor is broken
D. Lateral perforation
4. MB root of the 1-st upper molar:
A. It has only 1 canal
B. In the majority of cases it has 2 canals
C. Has the second peep-hole, which is located towards the DB
canal entrance
D. Has the second peep-hole, which is situated towards the
palatal canal entrance
5. What canal is the most lower in molar canal?
A. MB canal
B. ML canal
C. DB canal
D. DL canal
6. The sufficient access cavity opening:
A. Allows to clean the cavity completely
B. Makes the root canal instrumentation easier
C. The risk of a crown discoloration is the less possible
D. All are correct
7. What is the main purpose of access forming in the
pulpectomy?
A. To widen the cavity including the pulp chamber
B. To make a coronal pulp amputation
29
C. To localize the orifice and provide straight access to the root
canal
D. To widen the cavity including the pulp chamber and localize
peep-holes
8. What is the aim of using the rubber dam?
A. Well visible working site
B. Aseptic
C. To protect a patient from endodontic tools and materials
aspiration
D. everything is correct
9. Not aesthetic but endodontically correct access can be used
for:
A. Upper incisors
B. Upper canines
C. Lower incisors
D. Lower premolars
10. The shapes of the central and lateral upper incisors access
cavities most often are:
A. Similar due to the likeness of their crowns and roots
B. Triangle, and located in the incisor in the direction of the
enamel tubercle paracervical on the palatal tooth surface
C. Triangle and oval
D. Execute with a fissure-staight drill
11. The 1-st upper molar mesio-buccal root can include:
A. Usually 1 root canal
B. In most cases 2 root canals
C. Has the second root canal peep-hole, which is located
towards the MD peep-hole
D. Has the second root canal peep-hole, which is located
towards the P root canal peep-hole
30
12. The second upper molar morphologically differs from the
second upper molar in:
A. Divergent buccal roots
B. There are no parallel root canals
C. Three roots, which are located with each other
D. The right-angled shape of the tooth cavity bottom
13. The narrow access preparation:
A. Provides a good access to all root canals
B. Makes impossible the root canal access with a straight line
C. Allows a good pulp chamber cleaning
D. Provides a good visualization of the possible additional root
canals
14. In what cases the percentage of revealing the incisors with
two apical openings is possible:
A. 1%
B. 10%
C. 20%
D. 30%
15. In what cases the percentage of revealing the МВ2 root
canal in the first upper molar is possible:
A. 10%
B. 40%
C. More than 90 %
D. 60%
16. How can it be confirmed that the second canal is available?
A. To make an additional x-ray film in mesial or distal
horizontal angle
B. To change the access forming
C. To make the the X-ray angle larger in vertical plain
31
D. to make an additional intra-oral x-ray of teeth and jaw in
occlusion
17. Why is it recommended to estimate the working length,
cleaning and forming of the canal during the first (one) visit?
A. To prevent aggravation in the course of treatment
B. To limit the number of visits
С. To create the apical barrier
D. To provide the optimal space for the intracanal medication
Reference literature
1. Clincal endodontics: a textbook /Leif Tronstad.– 3rd rev.
ed.– New Yourk, 2009.– 249 p.
2. Stephen Cohen, Richard C. Burns. Pathways of the pulp.
Eighth edition.– Mosby, 2002.– 1031 p.
3. Fan B, Wu M-K, Wesselink PR. Leakage along warm
gutta-percha fillings in the apical canals of curved roots.
Endod Dent Traumatol 2000;16:29-33.
4. Glosson CR, Haller RH, Brent Dove S, del Rio CE.
Comparison of root canal preparations using NiTihand,
NiTi engine-driven and K-flex endodontic instruments. J
Endod 1995;21:146-51.
5. Molven O, Halse A, Grung B. Surgical management of
endodontic failures: indications and treatment results. Int
Dent J 1991;41:33-42.
6. Seltzer and Bender’s. Dental pulp // Quintessence
Publishing, 2002.
32
Practical lesson No 35
Theme:
Endodontic instruments.
Indications for use.
Classification.
Types.
Short description of a theme
Endodontics is the branch of dentistry that is concerned
with the morphology, physiology, and pathology of human
dental pulp and periradicular tissues.Its study and practice
encompass the biology of normal pulp and the etiology,
diagnosis, prevention, and treatment of diseases and injuries of
the pulp and associated periradicular conditions.
The scope of endodontics includes, but is not limited to,
the differential diagnosis and treatment of oral pain of pulpal
and/or periradicular origin; vital pulp therapy, including pulp
capping and pulpotomy; non-surgical treatment of root canal
systems and the obturation of these systems; selective surgical
removal of pathological tissues resulting from pulpal pathosis;
repair procedures related to surgical removal of pathological
tissues; intentional replantation and replantation of avulsed
teeth; root-end resection, hemisection, and root resection; rootend obturation; bleaching of discolored teeth; retreatment of
teeth previously treated endodontically; and treatment with
posts and/or cores for coronal restorations.
The success of basic nonsurgical endodontic treatment
is highly dependent on the triad of access cavity preparation,
proper cleaning and shaping of the root canals, and the quality
of the obturation of the root canal system. The long-term
prognosis is determined by the quality and integrity of the
coronal seal, ie, post-core-permanent restoration. It is therefore
imperative that further ingress of oral fluids (microleak-age),
through restorative and endodontic materials, be kept to a
33
minimum.
The second component of the endodontic triad involves
cleaning and shaping of the canals. Removal of the coronal
portion of the pulp is usually performed with a metallic spoon
excavator or a rotary bur on a slow-speed handpiece. For the
initial debridement of the canals, root canal broaches or rotary
orifice-shaping instruments can be used. Manufactured in a
number of sizes, the root canal broach is a very narrow,
flexible, round stainless steel instrument with barbs along its
shaft. Prone to breakage, the broach must be used passively in
the canal and should not engage dentin. It is designed to
removed gross amounts of pul-pal tissue in large canals by
locking remnants of pulp with its sharp barbs. Broaches can
also be used to remove cotton products that have been placed
in the chamber between appointments.
Newer to the marketplace are rotary orifice shapers,
which are made of flexible nickel-titanium. These variably
tapered instruments are used in special controlled-speed, hightorque handpieces. Their use in the canal is typically limited to
the coronal half of the canal. Because of their larger tapers,
they facilitate straight-line access to the root apex by removing
restrictive coronal dentin early in the cleaning and shaping
process.
Gates-Glidden instruments are commonly used to
enlarge canal orifices and shape the coronal portion of the
canal. Used in a slow-speed handpiece, they consist of flexible,
stainless steel, noncutting shafts with flame-shaped burs at
their tips. They are available in a variety of lengths and sizes.
Specially designed hand instruments known as files and
reamers are necessary for biomechanical instrumentation of the
various anatomical forms of root canals. K-files are tapered
metallic instruments made from rectangular, triangular, or
rhom-boidal cross-sectional wires. They are available in
stainless steel or nickel-titanium and are manufactured by
34
twisting or grinding the metal blank. Various cutting angles on
the wires are created to plane or scrape the walls of the canal.
Depending on the file design and canal size and curvature,
these files may be used in a push-pull, twisting, watch-winding,
or circumferential motion. The nature of the metal (nickeltitanium being five times more flexible than stainless steel), the
size of the instrument, and the cross-sectional configuration
determine the relative flexibility of each instrument. In order to
accommodate different root lengths, these instruments are
manufactured in lengths ranging from 21 to 31 mm. Moveable
silicone rubber stops on the instruments can be adjusted to correspond to the exact length of each canal. Many newer file
designs incorporate a noncutting tip, which can be used instead
of a cutting tip to help guide the file. Cutting tips can create
deviations in canal anatomy during instrumentation. Examples
of K-type files include Flex-R files (Miltex) (triangular cross
section), FlexoFiles (Dentsply) (triangular cross section), and
K-Flex files (Kerr Analytic) (rhomboidal cross section).
The size of the file is determined by the diameter of the
shaft 1 mm from the tip and is recorded in millimeters. For
example, a No. 25 K-file measures 0.25 mm in diameter 1 mm
from its tip. The standard taper for these instruments is a 0.02mm increase for every 1 mm up the shaft from its tip (the
length of the working blades). For instance, the width of a No.
25 K-file at 16 mm above its tip is 0.57 mm (0.25 mm + 16 x
0.02 mm). Most traditional instrument designs adhere to this
standard of sizing and tapering.
Another type of file is the Hedstrom file. These files are
long, thin, and tapered like K-files but are made from round
cross-sectional wires. Generally made from stainless steel or
nickel-titanium, these aggressive files have cutting angles that
are ground into the shaft and can only be used in a scraping or
rasping motion as the file moves out of the canal. Rotation of
Hedstrom files is con-traindicated because they tend to self35
thread and have a strong predilection toward fracture when
used in this manner. Like the K-files, Hedstroms are
manufactured in uniform sizes, tapers, and lengths. They are
used primarily for removal of bulk amounts of dentin.
Classical hand root canal reamers are long, tapered,
stainless steel instruments made from rectangular, triangular, or
rhomboidal cross-sectional wires. They cut only during
twisting and have fewer cutting edges than a typical K-file.
Their use has diminished over time due to their lack of
efficiency and their tendency to deviate from normal root canal
anatomy during use. More tapered rotary reamers made of
nickel-titanium have essentially replaced the stainless steel
hand reamer. These instruments have radial land-cutting regions along their shafts and thus have been termed "U"-bladed
in cross section. Like the orifice openers previously described,
rotary reamers are used in a slow-speed, high-torque, gearreduction, air-driven or electric handpiece. Their tapers range
from the standard 0.02-mm increase up to a 0.12-mm increase
per millimeter. Examples include Profiles (Dentsply), GT Rotaries (Dentsply), Quantec 2000 (Kerr Analytic), and
Lightspeed (Lightspeed).
Control questions to practical lesson
1. What tools can be used for the root canal primary covering?
Why?
2. What tools can be used for the root canal widening? Why?
3. What tools can be used for the obliterated root canal
primary covering? Why?
4. What is the advantage in rotary Ni-Ti endodontic tools
usage?
36
5. What are the indications for the use of ultra sound in
endodontics? What ultrasonic endodontic tools do you
know?
6. What endodontic tools for the lateral condensation do you
know? What is the algorithm of their use?
7. What endodontic tools for vertical (hot) condensation do
you know? What is the algorithm of their use?
8. What tools are more preferable for the root canal peepholes widening? What is the advantage?
9. What is the indication of the endodontic tools Golden
medium series in the root canal treatment.
10. The advantages of safety usage of endodontic system in the
treatment of the crooked root canal.
11. The modern rotary Ni-Ti endodontic tool. Composition.
Advantages. Disadvantages. Indication for usage. The
method of application.
12. The modern endodontic handpieces and engines. Indication
for usage. Advantages. Disadvantages..
13. Manual Ni-Ti endodontic tools. Types. Indication for
usage. Advantages. Disadvantages.
14. List all of the materials necessary for the proper placement
of a rubber dam on a tooth requiring endodontic therapy.
15. Discuss the types and properties of the materials used in
obturating a cleaned and properly shaped root canal.
16. Discuss the various types of instruments that can be used to
bioinechanically prepare the root canal.
Situation tasks and test control
1. What endodontic tool will be used primarily and secondarily
in case of manual root canal preparation?
A. К-file No15
B. К-reamer No10
37
C. GT-file 35/12
D. Н-file No15
2. What endodontic tool is preferable as manual in full-round
root canal preparation:
A. К-file
B. К-reamer
C. ProTaper
D. Н-file
3. When is the highest risk of endodontic tool fracture in the
full-round root canal preparation?
A. Manual
B. Rotary speed is 200 revolutions per minute
C. Rotary with a programmed round control
D. It is important
4. For what endodontic tool a full revolution is unacceptable?
A. К-file
B. К-reamer
C. С-file
D. Н-file
5. For what endodontic tool the «balance forces» method is the
most dangerous?
A. К-file
B. К-reamer
C. GT-file
D. Н-file
6. Endodontic tool of size No 10 is marked:
A. Red
B. Violet
C. Black
38
D. Blue
E. White
7. Endodontic tool of size No 20 is marked:
A. Red
B. Blue
C. Yellow
D. Black
E. White
8. Endodontic tool of size No 15 is marked:
A. Red
B. Blue
C. Black
D. Violet
E. White
9. Endodontic tool of size No 25 is marked:
A. Red
B. Blue
C. Black
D. Violet
E. White
10. Endodontic tool of size No 30 is marked:
A. Red
B. Blue
C. Black
D. Violet
E. White
11. Endodontic tool of size No 35 is marked:
A. Red
B. Blue
39
C. Black
D. Green
E. White
12. Endodontic tool of size No 40 is marked:
A. Red
B. Blue
C. Black
D. Green
E. White
13. To perform the root canal probing it should be used:
A. Miller needle
B. Н-file No15
C. К-file No10
D. H-file No15
14. All of the following endodontic instruments are designed to
remove dentin except which one:
A. K-file
B. reamer
C. broach
D. Hedstrom
15. The endodontic "triad" consists of which of the following:
A. Access, biomechanical instrumentation, and obturation
B. Rubber dam placement, access, and obturation
C. Biomechanical instrumentation, obturation, and restoration
D. Access, obturation, and restoration
16. All of the following are true about Hedstrom files except
which one:
A. They work best by rotation
B. They are made from a circular wire
40
C. They are manufactured in uniform sizes
D. They are made from either stainless steel or nickel titanium
metal
17. Which of the following is a chelating agent, helping to
loosen calcific obstructions in the root canal:
A. Gutta-percha
B. Roth's 801
C. Sodium hypochlo-rite
D. EDTA
18. Which of the following instruments is used in the lateral
condensation of gutta-percha:
A. Plugger
B. Spreader
C. Explorer
D. Broach
Reference literature
1. Clincal endodontics: a textbook /Leif Tronstad.– 3rd rev.
ed.– New Yourk, 2009.– 249 p.
2. Stephen Cohen, Richard C. Burns. Pathways of the pulp.
Eighth edition.– Mosby, 2002.– 1031 p.
3. Fan B, Wu M-K, Wesselink PR. Leakage along warm
gutta-percha fillings in the apical canals of curved roots.
Endod Dent Traumatol 2000;16:29-33.
4. Glosson CR, Haller RH, Brent Dove S, del Rio CE.
Comparison of root canal preparations using NiTihand,
NiTi engine-driven and K-flex endodontic instruments. J
Endod 1995;21:146-51.
41
5. Molven O, Halse A, Grung B. Surgical management of
endodontic failures: indications and treatment results. Int
Dent J 1991;41:33-42.
6. Seltzer and Bender’s. Dental pulp // Quintessence
Publishing, 2002.
Practical lesson No 36
Theme: Work with endodontic instruments. The use of
medications for cleaning of the root canal. Methods of
cleaning and widening of root canals.
Short description of a theme
Regulations concerning instruments designed to aid in
root canal preparation are governed by the International
Standards Organization. Instruments are numbered and colour
coded.
The number of each instrument refers to the diameter,
Dl, of the cutting blade at the tip of the shank. The number is
taken from the diameter Dl in millimetres x 100 e.g. If the
diameter at Dl is 0.25 mm the number of the instrument is 25.
D2 is the diameter of the cutting blade furthest from the tip of
the shank. The working part, which lies between Dl and D2, is
tapered, the degree of taper depending on the type of
instrument. Reamers and files have a taper of 0.02 mm per
mm of working length.
Colour coding. The International Standards
Organization (ISO) recommends a colour coding system
which has now been adopted by the majority of firms
42
manufacturing hand instruments, six colours were chosen in
ascending order of size from light to dark. These colours are
repeated in each of the 3 groups. The table on the right shows
the range of numbered instruments and their allotted colour
coding.
Instrument lengths. There are four standard lengths
manufactured 21 mm, 25 mm, 28 mm, and 31 mm measured
from the instrument tip to the base of the handle. These lengths
are adequate for the majority of teeth but occasionally longer
than 31 mm may be required and these can be ordered
specially.
Types of instrument. The various types of instrument in
use are illustrated, including several of the more recent designs.
Some instruments such as the smooth broach and rat tail files
are rarely used and are not described.
Barbed broach. These instruments are designed to
remove gross pulp tissue. They are made from soft steel and
have barbs notched into the shank. They must only be used in
the straight part of the canal. The size chosen should fit loosely
into the canal to avoid breakage. Reamer. The reamer is
produced by twisting a square or triangular tapered blank. A
reamer will cut only when it is rotated due to the angle of the
blade or flute.
K-File. The K-file received its name from the Kerr
Manufacturing Co., who were the first to produce it. The K-file
is constructed in the same way as a reamer except that there are
2% times the number of twists per unit length. The advantage
of the file is that it may be used to -cut dentine by either a
rotary movement or a filing action.
Flex-O-File2. A recent addition, the Flex-O-File is very
similar to a K-file but is manufactured with a softer more
flexible steel. It does not fracture easily and is so flexible that it
is possible to tie a knot in the shank.
43
K-Flexfilel. Another recent addition to the range of hand
instruments. It is similar to a K-file except that the shape of the
cross section is a diamond. This means that the instrument is
more flexible than a reamer or K-file and has a sharper blade.
Hedstroemfile. The instruments are machined from a round
tapered blank. A spiral groove is cut into the shank, producing
a sharp blade. Because of the angle of the blade the hedstroem
file should only be used with a filing action. If a rotary
movement is used and the blades engage the dentine there is a
danger of the instrument fracturing. Unifile. This relatively new
instrument is almost identical in appearance to the hedstroem
file, but it has two cutting blades instead of one. The grooves
cut into the shank of the Unifile remain at the same depth
throughout the working part. This increases the stiffness and
resistance to fracture in the coronal and middle thirds of the
instrument but allows greater flexibility in the apical portion
which corresponds to the position of the curve in most roots.
Helifile. The method of manufacture of the Helifile is
similar to the Hedstroem and Unifile except that in cross
section there are 3 blades. The appearance of the instrument
resembles a reamer rather than a Hedstroem file. Little
information is available yet concerning their cutting ability or
resistance to fracture.
Instrument Safety and Usage. An ever present danger
during root canal preparation is the fracture of an instrument
within the canal. This will be unlikely to occur if the following
steps are taken.
1. Instruments should be inspected before they are
inserted into the root canal. If there is any sign of the flutes
becoming either unwound or overtwisted the instrument should
be discarded. Instruments with a sharp bend in the shank
should also be thrown away. There is no guide to the number
of times an instrument should be used as this will depend upon
a number of factors. Smaller instruments will be discarded
44
more frequently than larger ones.
2. Never force an instrument into a canal. If an
instrument feels tight in the canal short of the working length it
should be removed and a smaller size used.
3. Reaming action. All instruments with the exception
of the Hedstroem file may be used with a reaming action. The
reaming action consists of a quarter to a half turn and
withdrawal. An instrument should not be screwed into the
canal as this invites fracture. The reaming action produces a
rounder hole than filing but should not be used in curved canals
as it will produce zipping in the apical portion of the canal.
4. Filing action is carried out by inserting the
instrument to the marked depth and then withdrawing it while
exerting even pressure on the wall of the canal. The instrument
is withdrawn a few mm, reinserted and the movement repeated.
The entire wall of the canal is filed by gradually working
circumferentially in a clockwise direction.
Control questions to practical lesson
1. What are the rules for preparation of access cavities in
endodontics?
2. Differences in the work with K-file and H-file in root canal
treatment.
3. What are the stages of root treatment in endodontics?
4. Describe methods of root instrumentation.
5. Describe Step-back technique in root canal instrumentation.
6. Describe Crown-down technique in root canal
instrumentation.
7. What groups of medications are used for root canal
cleaning?
8. What are the demands to antiseptics for root canal
cleaning?
45
9. How does antiseptic Na hypochloride influence vital
tissues?
10. Peculiarities of the treatment of the apical part of root
canal?
Situation tasks and test control
1. Sonic and ultrasonic root canals preparation systems are
used for:
A. The coronal part of the crown
B. Its rotary endodontic tools
C. Activating the irrigation solutions
D. Good method for the root canal preparation
2. For the root canal localization it is preferable to use:
A. Periodontal probe
B. Excavator
C. Round-shaped drill
D. Endoprobe
3. What definition as to the barber broach is correct?
A. Barber broach can be used in curved canals
B. Barber broach is carried out (put into operation) in the full
length
C. Barber broach can be carried out with press into the root
canal
D. The size of barber broach makes it possible to extract the
pulp, avoiding the root canal walls
4. Barber broach is a flexible manual endodontic tool with
sharp hooks and is used for:
A. Extraction of the roof of the pulp chamber
B. Extraction of the pulp tissue from the root canal
46
C. Finishing the root canal dentin
D. Making the apical barrier in the root canal apex
5. What is the difference between K-file and K-reamer?
A. Do instruments make the square cuts prior to preparation,
twist method
B. In the same length the spiral amount is different
C. All the reamers make the triangular cuts prior to preparation
D. K-file can be used as mechanical and manual endodontic
tools
6. A working part of the endodontic spreader is:
A. Smooth with a dull tip with a little conical form
B. Smooth with a dull tip with a cylindrical form
C. Smooth with a sharp tip with a slight conical form
D. Smooth with a sharp tip with a cylindrical form
7. The important factor in case of the endodontic tool fracture
in the root canal is:
A. Length
B. Diameter
C. Localization
D. Flexibility
8. In the majority cases the H-file is used for:
A. Widening the root canal from apex to the root canal
entrance
B. Making the round shaped form in the apical 1/3 length
C. Preparing the canal for restoration with a pin
D. For the dentin cutting with a rotary movement
9. Mechanical 3-th size piesoreamer is used for:
A. Extraction of the rest of the pulp and tissues
47
B. Instrumental preparation of the apical and medium parts of
the root canal
C. Finishing and polishing of all the canal walls
D. Finishing and widening the crown 1/3 length of the root
canal
10. What rotary tools are used for widening the coronal part of
the root?
A. Round-shaped bur
B. Gates-Glidden bur
C. Inverted-cone bur
D. Fissure-straight bur
Reference literature
1. Clincal endodontics: a textbook /Leif Tronstad.– 3rd rev.
ed.– New Yourk, 2009.– 249 p.
2. Stephen Cohen, Richard C. Burns. Pathways of the pulp.
Eighth edition.– Mosby, 2002.– 1031 p.
3. Fan B, Wu M-K, Wesselink PR. Leakage along warm
gutta-percha fillings in the apical canals of curved roots.
Endod Dent Traumatol 2000;16:29-33.
4. Glosson CR, Haller RH, Brent Dove S, del Rio CE.
Comparison of root canal preparations using NiTihand,
NiTi engine-driven and K-flex endodontic instruments. J
Endod 1995;21:146-51.
5. Molven O, Halse A, Grung B. Surgical management of
endodontic failures: indications and treatment results. Int
Dent J 1991;41:33-42.
6. Seltzer and Bender’s. Dental pulp // Quintessence
Publishing, 2002.
48
Practical lesson No 37
Theme: Root canal filling materials. Classification. Main
demands. Partially hardening sillers. Composition.
Characteristic. Indications for use.
Short description of a theme
For the root canal obturation three main types of the
points are used: Gutta-percha, resilon and silver.
Points can be divided into:
- metal: silver, titanium
- nonmetal: gutta-percha, plastic, resilon
Gutta-percha is a polymer matter, which composites
from the polyizopren, which obtained from the Malaysia
tropical tree. Gutta-percha – the coagulated, dried, purified
latex of trees of the genera Palaquium and Payena, most
commonly Palaquium gutta; used in orthopedics for fracture
splints, in surgery for temporary sealing of cavities and in
dentistry, in the form of cones for filling the root canal and in
the form of sticks for sealing cavities over treatment.
As a polymer, this matter has a viscous elasticity
feature. It means, that in a solid substance this matter possesses
elasticity propeties, but in liquid is a low flow fluid. On
heating, gutta-percha becomes soft quite easy. This material
heated to 65ºC temperature turns into liquid. It can be solved
by chloroform, eucalyptol xyleni.
The gutta-percha points can be standard and accessory.
The guttapercha points consist of 60-70% ZnO, 17%
hard metals salts, 1-4% different kinds of wax, antioxidants
and polymer compositions. The gutta-percha points contain just
20% of genuine guttapercha. It can have α and β forms. On the
heating to 42ºC - 44ºC β form is converted into the α form.
49
Absolute guttapercha dissolution occures in 56º C - 64ºC. After
cooling gutta-percha has a high shrinkage level. The standard
points have the same size that the standard endodontic tools.
The dentist can choose the tape of the point. It may be 02, 04,
06 type.
The main best feature of the gutta-percha points is their
biocompatibility. So this matter does not irritate the periapical
tissue. This point is x-ray visible, does not cause the
discolouration of the tooth and can be removed from the canal
easily.
Disadvantages: The single gutta-percha point fails to
provide the hermetic root canal isolation and protect it against
the spread of microbes.That is why it is recommended to use
points with a sealer to provide better root canal hermetization.
It has no adhesion to the dentin. The thin points are flexible
that makes it difficult to insert them into the canal.
The ISO standard points:
Size:
standard 15-140
accessory 15-55 (extra-fine,fine-fine,medium-fine,fine,
fine-medium, medium, medium-large, large, extra-large
Length
28 mm
Silver points are used as fillers from 30s of the XX
century. The metal posts can not provide the 3D root canal
obturation. The microleakage level is high. The silver points
ISO sizes are: 010, 015 and 020. The silver points can corrode
in blood and lymph. It forms the oxides of argentum, having a
toxic effect on the cells and tissues. These points can change
the colour of the tooth.
Methods of the root canal obturation.
a) Cold gutta-percha points:
1. central point method
2. lateral compaction method
50
b) Chemical-plastificated cold gutta-percha method with usage
of the special oil solutions:
c) Warm gutta-percha obturation method
1. Vertical condensation
2. Fragmentated gutta-percha obturation
3. lateral-vertical condensation
4. Termomechanical condensation
d) Termoplastificated gutapercha obturation
1. Injection method
2. two-phases gutapercha
3. hard-rod fitting method
The lateral compaction method means the 3D root
canal obturation without the thermal or chemical guttapercha
softening. This method can help to prevent the gutta-percha
shrinkage which can appear after the heating, and problems
with the point fitting. This method means that we have to
choose the suitable master-point which has the same size as the
last endodontic tool which was used for the apical part of the
root canal preparation. After that the doctor has to fit this point
on the whole length to the root canal and check the position
with the help of the periapical x-ray. Correct the point if it is
necessary. Mark the point relatively the reference on the
occlusal or incisal surface and remove it from the root canal.
The point has to be covered by sealer and fitted in the root
canal to the whole length to the mark The sealer can be put
inside the canal with the help of lentulo or manually. The
spreader should be inserted into in the root canal to the apical
narrowing if it is possible. The spreader’s size must be smaller
on the first step of obturation and it has to penetrate inside the
canal as deep as it is possible, but not deeper than the apical
narrowing. Later the greater sizes of spreader are used. The
srpeader compact the guttapercha to the lateral walls and make
a space for the additional points. Spreader has to be removed
from the root canal after 20 sec. The additional point which is
51
covered by the sealer is placed on the same length while the
lateral compaction. The additional point shouldn’t be softened.
This procedure should last to the full root canal obturation.
Cut the ends of the points in the crown. The x-ray control
should be made.
The one point method means that the root canal is
obturated by one point and sealer. With the help of endodontic
tools the apical narrowing is formed. The size and the shape of
the post have to be the same that the last tool for root canal
formation. For this purpose it is recommended to use Ni-Ti
rotary tools. After that we have to fit this point on the whole
length to the root canal and check the position with help of the
periapical x-ray. Correct the point if it is necessary. Mark the
point relatively the reference on the occlusal or incisal surface
and remove from the root canal.Cover the walls by the sealer.
The point should be covered by sealer and fitted in the root
canal to the whole length to the mark. Cut the ends of the
points which are situated in the crown.
Control questions to practical lesson
1. What are the fillers that can be used for the root canal
obturation?
2. What is the composition of the gutapercha point?
3. What is the composition of the resilon point?
4. What is the benefit in guttapercha points use?
5. What is the benefit in resilon points use?
6. Gutta-percha points: features, indication for use.
7. Resilon points: features, indication for use.
8. Silver points: features, indication for use.
9. Describe the lateral compaction method of the root canal
obturation.
52
10. Describe the vertical condensation method of the root canal
obturation.
11. Describe the one point method of the root canal obturation.
12. Describe the method of the root canal obturation with help
of the ultrasonic plastification.
13. Describe the method of the root canal obturation with help
of the gutta-condensor.
14. Describe the method of the root canal obturation with help
of the Ultrafil system.
15. What is meant under the definition „fillers”?
16. What indications and contraindications for the fillers use do
you know?
17. What indications and contraindications for the gutta-percha
points use do you know?
18. What indications and contraindications for the silver points
use do you know?
19. What indications and contraindications for the resilon
points use do you know?
20. Compare the gutta-percha and silver points.
21. Compare the gutta-percha and resilon points.
22. Compare the resilon and silver points.
23. Compare the vertical condensation method and the lateral
compaction method of the root canal obturation
24. Compare the vertical condensation method and the method
of the root canal obturation with help of the guttacondensor
25. Metal points: general classification. What are the
characteristic features of points. Features. Indication for
use.
26. Resilon points: general classification. What are the
characteristic features of the resilon points. Features.
Indication for use.
27. Gutta-percha points: general classification. Characterize the
gutta-percha points. Features. Indication for use.
53
Situation tasks and test control
1. For how long does the hot gutta percha possess its ability to
condensation?
A. 5 sec
B. 30 sec
C. 1 min
D. 2 min
2. The second upper incisor root canal is prepared to the
working length with No 35 К-file. What gutta percha points
can be used for the root canal filling?
A. Gutta percha point No 30
B. Gutta percha point No 35
C. Gutta percha point No 40
D. All is right
3. Which of the assertions as to the silver points is true?
A. Silver content in them is equal to 70%
B. Texture of their surface does not influence on the sealer
adhesion
C. They prove to be the least toxic in endodontics
D. They can be exposed to corrosion that has cytotoxic affect
4. Standard gutta percha post are used as the basic posts,
because they are:
A. Long, cone-shaped and thermoplastic
B. They can easily penetrate into the narrow, curved, canals
C. Of the same diameter and cone-shaped with instruments
used for root canals
D. Tough, strong and are easily inserted into the canal
5. If the roentgenography (X-ray) reveals that the standard
point is too short, than the dentist can:
54
A. Use the lubricant for its deeper insertion
B. Widen the canal by H-file (its dimensions corresponds to
master file) and repeat the insertion of the point
C. Use the new point but with smaller dimension
D. Apply it with apical effort
6. In case the X-ray shows that the standard gutta percha point
is a little bit shorter (up to 0,5 mm), than the dentist can:
A. Select the most suitable point among the rest of the same
size
B. Widen the canal with a help of K-file with a proper size
C. Use the lubricant for inserting the post with the apical effort
D. Use it, taking into account the necessity in filling a gap with
a sealer
7. In case the post is too long, the dentist can:
A. Select the point of greater size
B. Make shorter for 1 mm
C. Make shorter with, using the Maillefer caliber-rule
D. Insert point against the stop and shorten its excess according
to the X-ray showings
8. If it occurs that during the filling with a point, the master
post corresponds to the working length, but there is a space in
the canal the dentist is:
A. To fill it with the excessive amount of sealer
B. To insert along with sealer the additional 1-2 posts
C. While cutting the posts by hot plugger it is recommended to
condensate gutta-percha by cold plugger
D. All above mentioned cases
9. In what cases the obturation by a single gutta percha sealer
point with sealer is indicated?
A. Narrow (20-25) and curved canal after preparation
55
B. Slightly curved canal of the lateral upper incisor
C. An undeveloped canal in children
D. In all above-mentioned cases
10. In what cases the obturation of a canal by lateral
condensation method is recommended?
A. Narrow (20-25) and curved canal after preparation
B. Slightly curved canal of the upper lateral incisor
C. An undeveloped canal of the upper lateral incisor
D. In all above-mentioned cases
E. In all above-mentioned cases except for ….. A
11. Which of the below-mentioned instruments and materials
proved to be unnecessary for the lateral condensation?
A. Sealers
B. Standard gutta percha post
C. Spreaders
D. Pluggers
12. Which of the belowmentioned demands as to the form of
the canal preparation proved to be unnecessary for the tooth
filling by lateral condensation?
A. Apical narrowing
B. Apical projection
C. Even cone-shaping
D. Smooth walls
E. Round or oval form on transversal incision
13. How is the sealer introduced in lateral condensation?
A. By a canal filler with 200 rotations per minute that
completely fills the canal
B. A small amount of sealer is introduced into the canal with a
help of canal filler (200 rotations per minute)
56
C. A small amount of sealer is introduced into the canal with a
help of manual canal filler
D. Method of introduction and amount of sealer are not
important
14. The characteristics of obturation of the canal system in case
of proper lateral condensation. Which of the below enumerated
judgements are incorrect?
A. There is no material in the lateral canals
B. Gutta-percha is in the lateral canals
C. Sealer is in the lateral canals
D. Magistral canal is filled geometrically
15. Which of the enumerated statements proved to be correct?
A. Lateral condensation – the best filling
B. Vertical condensation – the best filling
C. Both fill the lateral canals with certainty
D. The ability to fill the canals depends on the form of the
canal which is to be prepared
16. Which of the enumerated instruments and materials proved
to be unnecessary for the vertical condensation?
A. Sealer
B. Gutta-percha based
C. Spreader – heat carrier
D. Plugger
E. Over for the gutta percha heater
17. In classical technique of the vertical condensation the
warning-up of gutta percha makes it soft. Which of the
following statements proved to be correct?
A. Before warming, the gutta percha-based post is adjusted but
not tightly along the length and diameter of the canal
B. Standard post is warmed up outside the canal
57
C. Gutta percha-based post becomes soft in the canal due to the
use of a heated acute-edged smooth instrument with regard for
the length and diameter of the canal
D. The heated plugger makes the gutta percha – based post soft
18. Which of the enumerated statements, as to the form of the
canal that is to be prepared, is obligatory for the cervical
condensation of the canal?
A. The presence of retention in the apical part of the canal
B. Even cone-shaping
C. Smooth walls
D. Round or oval form on the transversal incision
19. Working part of instruments for root canal filling. Which of
the following instruments is defined as a revolving condensor?
20. Which of the enumerated instruments and materials proved
to be unnecessary for filling with thermafil?
A. Sealer
B. Carrier of gutta percha – thermofil
C. Spreader – heat carrier
D. Over for gutta percha heating
21. What method of gutta percha filling the thermafil-based
obturation is referred to?
A. The application of cold gutta percha
B. The application of gutta percha softened by chloroform
C. The application of gutta percha softened by intracanal heat
58
D. The application of gutta percha softened by extracanal heat
22. What method of obturation the thermofil-filling is referred
to?
A. Method of lateral condensation
B. Method of central condensation
C. Method of vertical condensation
23. The best facilities for gutta percha sterilization are the use
of:
A. 90% alcohol
B. 3% hydrogen peroxide
C. 70% alcohol
D. 5,25% sodium hypochloride
24. For gutta percha sterilization it is preferable to use:
A. 90% alcohol
B. 3% H2O2
C. 70% alcohol
D. 5,25% NaOCl
25. The main purpose of canal obturation is:
A. To keep the balance of both the post material and root
cement in the canal
B. Three-dimensional filling of the canal space
C. The isolation of the basic canal from the tissue liquids
26. What is the obturation purpose?
A. Balancation of filler and sealer amount in the root canal
B. Root canal 3D obturation
C. Basic root canal isolation from surrounded tissue liquid
D. Filling the lateral and periapical endodontic lesions
27. The best filling material must:
59
A. Possess a sufficient shrinkage for canal filling
B. Readily fill the canal laterally and apically, adjoining its
walls
C. Resolve under the influence of the tissue fluids, without
causing irritation
D. Possess spongy surface for supporting the tissue growth
28. The best canal cement used with a semisolid point:
A. Fills the roughness between the filling and canal walls
B. As a rule, irritates the periapical tissues
C. Is radiopaque on applying, but not in final hardening
D. Influences insignificantly on the final result of treatment
29. Standard gutta percha posts are used as the main post
because they:
A. Are long, cone-shaped and soluted in the chloroform
B. Penetrate easily into the narrow curved canals
C. Their diameter and form is similar to the diameter and form
of the instruments used for root canals
30. Standardizated gutta percha points are used as master
points because:
A. They are long, taped and can be solved in chloroform
B. Can be good adaptated in curved root canals
C. Have the same diameter and shape as root canals endodontic
tools
D. They are hard,straight and can be easily adapted in the root
canal
Reference literature
1. Clincal endodontics: a textbook /Leif Tronstad.– 3rd rev.
ed.– New Yourk, 2009.– 249 p.
60
2. Stephen Cohen, Richard C. Burns. Pathways of the pulp.
Eighth edition.– Mosby, 2002.– 1031 p.
3. Fan B, Wu M-K, Wesselink PR. Leakage along warm
gutta-percha fillings in the apical canals of curved roots.
Endod Dent Traumatol 2000;16:29-33.
4. Glosson CR, Haller RH, Brent Dove S, del Rio CE.
Comparison of root canal preparations using NiTihand,
NiTi engine-driven and K-flex endodontic instruments. J
Endod 1995;21:146-51.
5. Molven O, Halse A, Grung B. Surgical management of
endodontic failures: indications and treatment results. Int
Dent J 1991;41:33-42.
6. Seltzer and Bender’s. Dental pulp // Quintessence
Publishing, 2002.
Practical lesson No 38
Theme: Filling of the root canals with partially hardening and
hardening sealers and fillers.
Short description of theme
Seallers - hardening materials, which are used for
filling of the empty spaces between the point and the root canal
walls while the root canal obturation.
It is used:
- for additional lateral root canals obturation;
- to form the compact layer between the point and a root
canal walls;
- to isolate not straight spaces on the root canal walls.
61
The properties of the seallers should be as follows:
- the high adhesion level to the root canal walls;
- it should lead easily into the root canal;
- provide full hermetisation of the basic root canal and
delts;
- be visible on X-ray film;
- the low shrinkage after the hardening;
- the small particles of sealler filler;
- should not paint the tooth;
- must possess bacteriostatic effect;
- must have the low time hardening;
- must be resistant to solubility;
- must not irritate the periapical tissues;
- in case of the retreatment provide the possibility to be
solved by special solvents;
- do not have the mutagenic and cariogenic features;
- must have no influence on the immune system.
ZOE- high effective endodontic hermetic. They formed
according to Rickert formula, and include next components:
- ZnO – 42%;
- Stabelith resin – 27%;
- Bismuth subcarbonate – 15%;
- BaS – 15%;
- Borat Na waterfree – 1%;
- Eugenol;
As supplements can be used : antiseptics, hormones and
others.
„Endomethasone”, „Endobtur”, „Estesone” (Septodont),
„Cariosan” (Spofa Dental).
Sealler which is based on the epoxide resins. This is
sealler „paste-paste” or „powder-liquid” type which is
hardening after the mixing in temperature 36ºC which is last 836 h. This type sealers: AH-26, AH-plus (Dentsply), “Diaket”
(ESPE).
62
Seallers, which contain Ca(OH)2 can stimulate the
mechanism of cementoblastes integration. As a result it can
form the apical barier. The bone tissue revival is possible in
case of this type sealler usage. Ca(OH)2 – white powder with
12,5 pH level.( it is very important, because this pH level
possesses with antiseptic property. The modern materials:
„Sealapex” (Kerr), „Apexit” (Vivadent), „Endocal”
(Septodont)
Glassionomers.
This type of materials has a chemical adhesion to dentin
that provides long and reliable root canal obturation. The
glassionomer for the root canal obturation hardening time is
1,5- 3 h. It can be used in case of wall perforation or when the
wall thickness is small.The most popular in this group is:
„Ketac-Endo Apical” (ESPE), „Endition” (VOCO).
The sealler disadvantages:
- cytotoxity that gets weaker while the hardening;
- it can dissolve, that lead to bad obturation hermetcity
and microleakage;
- the sealler components while spreading in periapical
tissues, can provoke the chemical and mechanical
irritation;
- do not hermetically sealedroot canal system obturation;
- necessity of the fillers usage.
Control questions to practical lesson
1. What are the advantages and disadvantages of ZOE sealler
usage?
2. What is the advantage and disadvantage of glassionomer
sealler using?
3. What is the advantage and disadvantage of epoxyde resin
sealler using?
63
4. What is the advantage and disadvantage of use the sealer
which contain Ca(OH)2?
5. What is meant under the definition „sealler”?
6. Mistakes and complications which can be in work with
ZOE sealler.
7. Mistakes and complications which can be in work with
glassionomer sealler.
8. Mistakes and complications which can be in work with
epoxyde resin sealler.
9. Mistakes and complications which can be in work with the
sealer which contain Ca(OH)2.
10. Indication and contraindication for a sealler use.
11. Indication and contraindication for the ZOE sealler
12. Indication and contraindication for the glassionomer sealler
13. Indication and contraindication for the epoxyde resin
sealler
14. Indication and contraindication for the sealler which
include Ca(OH)2.
Situation tasks and test control
1. Standard gutta-percha posts are used as the main post
because they:
A. Are long, cone-shaped and dissolved in the chloroform
B. Penetrate easily into the narrow cursed canals
C. Their diameter and form is similar to the diameter and form
of the instruments for root canals
2. Standartizated gutta-percha points are used as master points
because:
A. They are long, taped and can be dissolved in chloroform
B. Can be easily adapted in curved root canals
64
C. Have the same diameter and shape as root canals endodontic
tools
D. They are hard,straight and can be adapted easily in the root
canal
3. The main gutta-percha post must be closely inserted into the
canal:
A. Apical 1/3 length
B. In the 1/3 length
C. Throughout the entire canal
D. All over the canal
4. The main compound for the majority root cements is:
A. Epoxy resin
B. Polyvynil resin
C. Zinc-oxide-eugenol
D. Precipitated silver
5. At present, the most commonly used root canal cement
(sealer) is:
A. Rikert’s sealer
B. Vakha’s sealer
C. Chloropercha
D. Grossman’s type sealers
6. Prior to gutta percha filling, the canal is prepared with due
regard to its walls:
A. They are to be parallel lengthwise
B. They slightly converged to apical narrowing
C. They are the widest in the apical and mesial 1/3 length of
the root
D. They extend to apical opening
7. Which of statements about gutta percha is true?
65
A. Gutta-percha-based posts contain 20% of it
B. Its molecular elastic properties improve the hermeticity of
the canal filling
C. The use of gutta-percha alongwith chemical solved
possesses the space stability
8. Which of the statements, concerning silver points is true?
A. The content of silver in them is approximately about 70%
B. Texture of their surface does not influence on the root canal
adhesion
C. They prove to be the least toxic in endodontics
D. They can be exposed to corrosion, that possesses the
cytotoxic affect
9. What statement about the silver points is true?
A. Silver points contain 70% of silver
B. Silver points corrosion can be cytotoxic
C. They are the least toxic materials in endodontics
D. The surface of pin does not effect on sealler adgesion
10. Free eugenol in the root canal sealer increases:
A. Space stability
B. Hardening time
C. Cytotoxic effect
D. Firmness
11. Paraformaldehyde-containing cements of root canals can be
used in:
A. Temporary pulpotomy
B. Treatment of necrotic pulp
C. Root canal filling
12. Sealers that contain paraformaldehyde can be used in:
A. Temporary pulpotomy
66
B. Pulpectomy
C. Necrotizing pulp treatment
D. Obturation
Reference literature
1. Clincal endodontics: a textbook /Leif Tronstad.– 3rd rev.
ed.– New Yourk, 2009.– 249 p.
2. Stephen Cohen, Richard C. Burns. Pathways of the pulp.
Eighth edition.– Mosby, 2002.– 1031 p.
3. Fan B, Wu M-K, Wesselink PR. Leakage along warm
gutta-percha fillings in the apical canals of curved roots.
Endod Dent Traumatol 2000;16:29-33.
4. Glosson CR, Haller RH, Brent Dove S, del Rio CE.
Comparison of root canal preparations using NiTihand,
NiTi engine-driven and K-flex endodontic instruments. J
Endod 1995;21:146-51.
5. Molven O, Halse A, Grung B. Surgical management of
endodontic failures: indications and treatment results. Int
Dent J 1991;41:33-42.
6. Seltzer and Bender’s. Dental pulp // Quintessence
Publishing, 2002.
Practical lesson No 39
Theme: Methods of fillings of the root canals. Mistakes and
complications during endodontic manipulations, their
reasons and ways of removal.
67
Short description of a theme
Materials and Instruments for Root Canal Obturation.
The goal of obturation is to seal off the root canal and
its ramifications from oral fluids and bacteria. Although there
is no ideal filling material, gutta-percha and sealer cements
have proved to be the materials of choice in contemporary
endodontics because they exhibit minimal toxicity and tissue
irritability when confined to the root canal system.
Gutta-percha.
Originating from special trees in Africa and South
America, pure gutta-percha is considered to be an isomer of
natural rubber known as trans-polyisoprene and is less elastic,
more brittle, and harder than natural rubber. It can exist in both
alpha and beta crystalline forms; these forms are
interchangeable depending on the temperature of the material.
The alpha form is the natural state, is less subject to shrinkage,
and is often used in obturating systems that use
thermoplasticized, or heat-softened, gutta-percha. The beta
form, which is typically found in gutta-percha cones or points,
is used in cold compaction techniques such as lateral condensation. Gutta-percha cones or pellets used in various
obturation techniques contain approximately 19% to 22%
gutta-percha, 59% to 75% zinc oxide, and a series of other
additives, including waxes, coloring agents, antioxidants, and
metallic salts.
The gutta-percha cone or pellet, in conjunction with a
root canal sealer, must be compacted in the canal to conform to
the prepared root canal system. Gutta-percha cones are
available in standardized and nonstandardized forms. The
standardized forms conform to the same dimensions and
uniformity as those used for endodontic files; thus, a No. 40
gutta-percha cone should reasonably fit a canal that has been
properly prepared with a No. 40 file. The nonstandardized
68
forms, classified as medium, medium-fine, or fine-fine, have
greater tapers than standardized cones and are often used in
techniques that involve vertical compaction of heat-softened
gutta-percha or filling of the coronal two thirds of a canal after
a standardized cone has been compacted in the apical third.
A couple of obturating techniques and instruments can
be used to compact gutta-percha into the root canal system. In
lateral condensation, a long (17- to 30-mm), tapered, metallic
instrument with a pointed tip known as a spreader is used to
compact the gutta-percha cones and sealer laterally against the
canal walls. Spreaders are available in both hand and finger
forms and are made of stainless steel or nickel-titanium for
greater flexibility. Root canal pluggers are used in the vertical
condensation method. These are long, slightly tapered, metallic
instruments with flattened or blunt tips. Available in both hand
and finger types, pluggers are designed to compact guttapercha and sealer vertically after the gutta-percha has been
thermosoftened with a hearing device.
Root canal sealers.
Root canal sealers are used to cement the gutta-percha
in place, to fill voids and the intricate ramifications of the canal
system, and to lubricate the cones during lateral compaction of
the relatively nonrigid gutta-percha points. They should be
biocompatible with and well tolerated by periradicular tissues.
The most commonly used sealers are zinc oxideeugenol (ZOE) and calcium hydroxide-based cements because
of their good working properties, sealability, biocompatibility,
and ease of removal. Resin-, glass-ionomer-, and siliconebased sealers are also available but are more technique
sensitive, difficult to remove, and have variable sealing
properties.
When mixed into a thick, creamy consistency, sealers
are placed inside the root canal via paper points or a lentulo
spiral, or are deposited in a light layer through the counter69
clockwise rotation of an endodontic file. Examples of
endodontic sealers include Roth's 801 (ZOE-based, Roth
Drug), Pulp Canal Sealer (ZOE-based, Kerr Analytic),
Sealapex (calcium hydroxide-based, Kerr Analytic),
ThermaSeal Plus (resin-based, Dentsply), and Ketac Endo
(glass ionomer-based, 3M ESPE).
Adjunct Materials
Calcium hydroxide
Calcium hydroxide has been used in dentistry for many
years, both as an intracanal medication and as a pulp-capping
agent. It is available in a variety of forms, ranging from pure
chemical grade to proprietary compounds (CalaseptJS Dental;
Tempcanal, Pulpdent). For intracanal use, calcium hydroxide
has been proven to be antibacterial and may aid in the
dissolution of necrotic pulp tissue. Its high pH is responsible
for the destruction of bacterial cell membranes and protein
structures. When pulps are exposed during routine cavity
preparation, a pulp-capping agent such as Dycal (calcium
hydroxide [Dentsply]) or mineral trioxide aggregate (discussed
later in this section) can be placed as a "bandage" over the
bleeding tissue in an attempt to promote dentinal bridge
formation over time, thus preserving the vitality of the pulp.
Mineral trioxide aggregate.
Mineral trioxide aggregate (MTA) (ProRoot, Dentsply)
is one of the newest and most promising materials to enter the
realm of endodontics in many vears. This root canal repair
material is a grayish powder consisting of fine, hydrophilic
particles that set in the presence of moisture. The hydration of
the powder, composed of tricalcium silicate, tricalcium
phosphate, tricalcium oxide, and others, creates a colloidal gel
that solidifies to form a strong impermeable barrier. The
material sets within 3 to 4 hours and has a working time of 5
minutes; it has been shown to be biocompatible and its seal is
superior to that of amalgam. Although the material is
70
somewhat costly and difficult to work with, primarily due to its
naturally sandy consistency when hydrated, the indications for
its use include clinical situations that often have no other viable
options, such as perforation repair. Indications for ProRoot
include pulp capping, internal repair of perforations
(noncommunicative), apexification, and root-end filling in
endodontic surgery.
Gutta-percha. The purified coagulated exiidate from
the mazer wood tree. It is a high-molecular-weight
stereoisomer of polyisoprenc. Since the 1950s, material
compounded in the United States for "gutta-percha" points has
been made from balata, a nearly identical latex from a special
tree in South America.
Irrigants. Liquids used to dissolve and flush out root
canal debris; examples include sodium hypochlorite, saline,
and hydrogen peroxide.
Obturation. The complete filling and closing of a
cleaned and shaped root canal with a root canal sealer and core
filling material.
Control questions to practical lesson
1. What is the goal of root canal obturation?
2. What types of endodontic posts for root canal obturatyion
do you know?
3. Describe the features of gutta-percha cones.
4. What are the most commonly used endodontic sealers?
5. What techiques of root canal filling do you know?
6. Describe root canal filling technique with central guttapercha point.
7. Describe root canal filling technique with lateral
compaction of gutta-percha points.
71
Situation tasks and test control
1. Which of the assertions as to the silver points is true
(correct)?
A. Silver content in them is equal to 70%
B. Texture of their surface does not influence on the sealer
adhesion
C. They prove to be the least toxic in endodontics
D. They can be exposed to corrosion that has cytotoxic affect
2. Standard gutta-percha post are used as the basic posts,
because they are:
A. Long, cone-shaped and thermoplastic
B. They can easily penetrate into the narrow, curved, cursed
canals
C. Of the same diameter and cone shaping with instruments
used for root canals
D. Tough, strong and are easily interested into the canal
3. In case the X-ray shows that the standard gutta-percha point
is a little bit shorter (up to 0,5 mm), then the dentist can:
A. Select the most suitable point among the rest of the same
size
B. Widen the canal with a help of K-file with a proper size
C. Use the lubricant for inserting the post with the apical effort
D. Use it, taking into account the necessity in filling a gap with
a sealer
4. Which of the mentioned instruments and materials proved to
be unnecessary for the lateral condensation?
A. Sealers
B. Standard gutta percha post
C. Spreaders
D. Pluggers
72
5. How is the sealer introduced in lateral condensation?
A. By a canal filler with 200 rotations per minute that
completely fills the canal
B. A small amount of sealer is introduced into the canal with a
help of canal filler (200 rotations per minute)
C. A small amount of siler is introduced into the canal with a
help of manual canal filler
D. Method of introduction and amount of sealer are not
important
6. Working part of instruments for root canal filling. Which of
the following instruments is revolving condensor?
7. Which of the enumerated instruments and materials are
unnecessary for filling with thermofil?
A. Sealer
B. Spreader – heat-carrier
C. Carrier of gutta-percha – thermofil
D. Over for gutta-percha heating
8. The best facilities for gutta-percha sterilization are the use
of:
A. 90% alcohol
B. 3% hydrogen peroxide
C. 70% alcohol
D. 5,25% sodium hypochloride
9. For gutta-percha sterilization it is better to use:
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A. 90% alcohol
B. 3% H2O2
C. 70% alcogol
D. 5,25% NaOCl
10. The ideal filling material must:
A. Possess a sufficient shrinkage for canal filling
B. Readily fill the canal laterally and apically, adjoining its
walls
C. Resolve under the influence of the tissue fluids, without
causing irritation
D. Possess spongy surface for supporting the tissue growth
11. The ideal canal cement used with a semisolid point:
A. Fills the roughness between the filling and canal walls
B. As a rule, irritates the periapical tissues
C. Is radiopaque an applying, but not in final hardening
D. Influences insignificantly on the final result of treatment
Reference literature
1. Clincal endodontics: a textbook /Leif Tronstad.– 3rd rev.
ed.– New Yourk, 2009.– 249 p.
2. Stephen Cohen, Richard C. Burns. Pathways of the pulp.
Eighth edition.– Mosby, 2002.– 1031 p.
3. Fan B, Wu M-K, Wesselink PR. Leakage along warm
gutta-percha fillings in the apical canals of curved roots.
Endod Dent Traumatol 2000;16:29-33.
4. Glosson CR, Haller RH, Brent Dove S, del Rio CE.
Comparison of root canal preparations using NiTihand,
NiTi engine-driven and K-flex endodontic instruments. J
Endod 1995;21:146-51.
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5. Molven O, Halse A, Grung B. Surgical management of
endodontic failures: indications and treatment results. Int
Dent J 1991;41:33-42.
6. Seltzer and Bender’s. Dental pulp // Quintessence
Publishing, 2002.
Practical lesson No 40
Theme: Module control.
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