Endo

1. Armamentarium & Sterilization
in Endodontics
Materials, instruments, and devices
4th Level
Lec. 6
Associate Professor Dr. Ahmed Madfa
Department of Conservative Dentistry, Faculty
of Dentistry

2. Diagnostic instruments
• Visual Aids
• Vitality
Testing
• Radiographic
Examination

3. Visual Aids
Vitality Testing
Transillumination
Neural
Magnifying Loops
EPT
Surgical Microscopes
Thermal
Vascular
Laser Doppler
Apex Locators
Radiography
Plain Radiograph
CT-scan

6. Basic instrument pack

7. (A) Front surface mirror; (B) endodontic locking tweezers; (C) DG16 endodontic explorer; (D) Briault probe; (E)
long-shank excavator; (F) surgical haemostat; (G) millimetre ruler; (H) amalgam plugger; (I) flat plastic.

8. A front-surfaced mouth
mirror produces an
undistorted image for good
visibility deep within the pulp
chamber..

9. The endodontic explorer is a double-ended, extra-long,
sharp instrument designed to help in the location of
canal entrances and for detecting fractures.

10. A long spoon excavator is required to remove pulpal
contents and soft caries

11. Locking tweezers are ideal for handling paper points,
gutta-percha points, cotton wool pellets and root canal
instruments.

12. Briault probe is necessary for the initial
assessment of the tooth for caries
Periodontal probe is necessary for the localized
periodontal condition

13. Amalgam plugger are needed for placement of an inter-
appointment restoration.
Glick No. 1 or Plastic instrument: double ended instrument one
end is flat used to carry the T.F material; while the other end used as
a condenser for the cement materials to the floor of the pulp
chamber after completion of root canal treatment or removal (and
then condensation) of excess gutta-percha with the heated plugger
end

14. Glick #1 instrument

15. A millimetre ruler or other measuring
device should be available for measuring
purposes.
Endodontic ruler: it’s a metal ruler
of 0.5 mm divisions, convenient for
the measuring of reamer, file and
gutta-percha lengths.

16. A surgical haemostat or forceps can be used to
position X-ray films, for radiography during
treatment.
Demo: Demo12-1 Endodontic Instruments.flv

17. Instruments for access
cavity preparation

18. Access cavity burs (left to right): (A) FG 557 ISO 010 (TC); (B) FG ISO round (long); (C) FG ISO
round (long); (D) safe-ended diamond ; (E) FG safe-ended TC, Endo Z (Dentsply Maillefer).

19. Burs
Friction grip burs
 Friction grip tapered or cylindrical fissure burs are used
in the initial stages of access preparation to establish the
correct outline form.
 For penetrating ceramic or composite materials,
diamond-coated burs are needed.

20. Tools
diamond through porcelain
carbide through metal and
tooth
Bur Brushing

21. Round burs
• Round burs, normal and extra-long
are used to lift the roof off the pulp
chamber and eliminate overhanging
dentine.
• If a standard length bur is too
short, burs with longer shanks, up to
28 mm, are available.
• The longer and smaller sizes of burs
may be used to remove dentine
when opening calcified canals.

22. Safe-ended burs
 Following initial access to the
pulp space, a safe-ended or non-
cutting tip, tapered diamond or
tungsten-carbide bur (e.g. Endo
Z bur, Dentsply Maillefer), can
be used to remove the entire
roof of the pulp chamber.
 The non-cutting tip prevents
‘gouging’ of the pulpal floor.

23. LAAXXESS

25. Simple Color Coding
.20
.35
.45
TiN Coating
Parabolic Tip
Stainless Steel

27. Instruments for root canal
Preparation

28. o Gates-Glidden drills are elliptically
(flame) shaped burs with a latch
attachment.
o Gates-Glidden burs are made of
stainless steel and the set of six
different sizes of burs have cutting
bulbs with diameter ranging 0.4–1.4
mm (1-6).
o The Gates-Glidden bur is operated at
low-speed.
o Gates-Glidden drills are used to open
the orifice.
o They also achieve straight-line access by
removing the dentin shelf and rapidly
flaring the coronal and middle third of
the canal.
o In retreatment cases, Gates-Glidden
burs can be used to remove gutta-
percha in the coronal part of the root
canal.
o Should be used only in the straight
sections of the canal.
Gates-Glidden burs

30. Peeso-Reamer Drills
• Peeso-reamers are also used as
adjunctive devices in canal
preparation
• They are basically similar to
Gates-Glidden drills but have
parallel cutting sides rather than
an elliptical shape.
• Peeso-reamers have been
suggested as a means of
improving straight-line access
• Peeso-reamers are not flexible or
adaptable, if not used with care
can perforate canal

32. o Used to create a funnel shaped opening into the
root canal.
o Enlarging the root canal orifice is helpful during
instrumentation and obturation phases.
Orifice Opener

33.  Micro-Openers are
excellent instruments for
locating canal orifices
when a dental dam has
not been placed.
 These flexible, stainless
steel hand instruments
have #.04 and #.06
tapered tips.
 They also have offset
handles that provide
enhanced visualization of
the pulp chamber.
Micro-Openers

34. Ultrasonic Unit and Tips
• An ultrasonic unit and tips specifically designed for
endodontic procedures can be valuable aids in the
preparation of access cavities.
• Ultrasonic tips can be used to trough and deepen
developmental grooves to remove tissue and
explore for canals.
• Ultrasonic systems provide excellent visibility
compared with conventional handpiece heads,
which typically obstruct vision.
• Fine ultrasonic tips are smaller than conventional
round burs, and their abrasive coatings allow
clinicians to sand away dentin and calcifications
conservatively when exploring for canal orifices.

35. • These instruments are manufactured by hacking a round, tapered
wire with a blade to form sharp, projecting barbs that cut or snag
tissue.
Function
1. Removal of pulp tissue from wide root canals
2. Cotton wool dressings from the pulp chamber.
3. Removal of pulp requires a broach that will not bind and yet is
large enough to ensnare the tissue. Binding should be minimized
because of possible breakage
Barbed broaches

36. • Hand instruments are grouped according to usage
and to the classification established by the
International Organization for Standardization
(ISO).
• The terminology, dimensions, physical properties,
measuring systems and quality control of
endodontic instruments and materials are defined
by these standards.
Hand-Operated Instruments

37. One technique involves machining (grinding) the
instrument directly on a lathe; an example is the
Hedström-type file. All nickel-titanium instruments are
machined.
1. Machined
Hedström file, machined by rotating a wire
on a lathe. Note the spiral shape. These are
efficient cutters (on the pull stroke) but are
more susceptible to separation when
locked and twisted.
Techniques for manufacturing of hand instruments

38. Some manufacturers produce K-type files using the machined (lathe-
grinding) process.
The machined file has less rotational resistance to breakage than a
ground-twisted file of the same size.
B and C, A machined K-type file. Note that
the transition angle at the leading cutting
edge of the tip is rounded, rendering it
noncutting.

39. 2. Ground-Twisted
1. Raw wire is ground into tapered geometric blanks: square, triangular,
and rhomboid.
2. The blanks are then twisted counterclockwise to produce helical cutting
edges.
K-type files have more twists per millimeter of length than the
corresponding size of K-type reamer.
Ground-twisted instruments. A, A square file blank
ground from wire. After twisting counterclockwise,
the appearance of a file (more flutes) (B) and
reamer (fewer flutes) (C).
These are K-type files and reamers.

40. Demo: Demo12-1 Endodontic Instruments.flv

41. Lengths
• Files and reamers are available in three shaft lengths: 21,
25, and 31 mm.
• Shorter instruments afford improved operator control
and easier access to posterior teeth, to which limited
opening impairs access.
• The 25- and 31-mm instruments are used for longer
roots.
• The 25-mm instruments are the most commonly used
instruments during root canal preparation.

42. Morphologic file selection

43. Sizing
• File tip diameters increase in 0.05-mm increments from size 10 up to the size 60 file
(0.60 mm at the tip), and then by 0.10-mm increments up to size 140.
• The diameter at the tip of the point is known as D1. The spiral cutting edge of the
instrument must be at least 16 mm long, and the diameter at this point is D16.
• The file diameter increases at a rate of 0.02 mm per running millimeter of length.

44. • The nickel-titanium rotary instruments
have other variable tapers of 0.04 and
0.06.
• For every millimeter of length, the
diameter increases by 0.04 or 0.06 mm.
• These greater tapers make these more
aggressive in creating marked flaring
preparation.

46. Tip Design
 Originally, the tip angle of K-type files and reamers was
approximately 75 degrees plus or minus 15 degrees.
 This design was intended to provide cutting efficiency without
an excessively sharp transition angle.

47. Torsional Limits (point of breakage)
 Torsional limit is the amount of rotational torque that
can be applied to a “locked” instrument to the point of
breakage (separation).
 Smaller instruments (less than size 20) can withstand
more rotations without breaking than larger (greater
than size 40) instruments.

48. Color Coding
Color coding of file handles designates size. Color
coding of the newer nontraditional instruments
varies according to the manufacturer.

50. Hand-Operated Instruments
• Several cross-sectional shapes of files and
reamers are commercially available.

51. Reamers
Reamer: Design & Structure
 Reamers are K-type instruments (manufactured by Kerr
company), which are used to ream the canals. They cut by
inserting into the canal, twisting clockwise one quarter to
half turn and then withdrawing, i.e. penetration,
rotation and retraction.
 Reamers have triangular blank and lesser number of flutes
than files. Numbers of flutes in reamer are ½-1/mm.
 Though reamer has fewer numbers of flutes than file,
cutting efficiency is same as that of files because more
space between flutes causes better removal of debris
 Reamer tends to remain self centered in the canal
resulting in less chances of canal transportation.
Triangular blank
and lesser number
of flutes in reamer

52. Reamer: Sizes & Codes
Reamers come in sizes 06 - 140, all with a taper of 0.02.

53. Reamer: Recommended use
• A reamer is the most effective hand instrument in straight canals.
• It is used by continuous rotation (upper picture) when the resistance
is small or moderate and by balanced force (lower picture) when the
resistance is greater.
• In curved canals ledging easily occurs with even small reamer sizes if
instruments are not pre-curved.
• Reamers are excellent instruments in straight canals but poorly
adaptable to curved canals.

54. Flexoreamer
Flexoreamer: Design & Structure
• Flexoreamers are manufactured from a triangular steel wire that is
twisted to give the typical shape of a reamer.
• The angle between the long-axis and the cutting blade is small, and
therefore preparation by flexoreamer is effective only in rotatory
motion.
• The tip of the instrument is non-cutting ('bat-tip', 'inactive tip')
making flexoreamer well suited for the preparation of evenly curved
canals without risk of ledging.

55. Flexoreamer: Sizes & Codes
• Flexoreamers come in sizes 15 - 40, all with a taper of 0.02.

56. Flexoreamer: Recommended use
• The flexoreamer is well suited both for straight canals and slightly
curved canals.
• It prepares dentin in rotation.
• The cutting efficiency and usability of flexoreamers are excellent.
In slightly curved canals the recommended techniques are
continuous rotation (upper picture) when the resistance is small
and balanced force (lower picture) against greater resistance.

57. There are various types of root canal file, and they are
mostly made from stainless steel.
The common types of files on the market are:
1. K-file
2. Flexofile
3. Hedström file.
Files

58. • This file introduced by the Kerr Company.
• K-files are manufactured from square or triangular steel wire.
• K-files have 1½ to 2½ cutting blades per mm of their working end.
• Tighter twisting of the file spirals increases the number of flutes in
files (more than reamer).
• Triangular cross-sectioned files show superior cutting and increased
flexibility than the file or reamers with square blank
Disadvantage of K-files
1. Less cutting efficiency.
2. Extrusion of debris periapically.
K-file: Design & Structure

60. K-file: Sizes & Codes
K-files are produced in sizes 06 - 140, all with a taper of 0.02.

61. K-file: Recommended use
• The K-file is suited for the preparation of straight canals.
• It prepares dentin effectively both in filing motion (up and down)
and rotated.
• In slightly curved canals the recommended techniques are
continuous rotation (lower picture) when the resistance is small
and balanced force (upper picture) against greater resistance.
• Compared to reamers, the use of continuous rotation is limited
because of the screwing effect typical of K-files.

63. Flexofile
FlexoFile: Design & Structure
• Flexofiles are manufactured from rhomboid
shaped steel wire.
• The angle between the long-axis and the cutting
blade is bigger than in reamers, which is why
preparation by flexofile is effective both in
rotating motion and in filing motion (up and
down movement)
• The tip of the instrument is non-cutting which
makes the flexofile well suited for the preparation
of evenly curved canals without the risk of ledge
formation

64. FlexoFile: Sizes & Codes
• Flexofiles come in sizes 15 - 40, all with a taper of 0.02.

65. FlexoFile: Recommended use
• Flexofile is suited for both straight canals and slightly curved canals.
• The flexofile prepares dentin effectively both in filing motion (up
and down) and rotated.
• In slightly curved canals the recommended techniques are
continuous rotation (lower picture) when the resistance is small and
balanced force (upper picture) against greater resistance.
• Use of continuous rotation is limited as compared to reamers
because of the screwing effect typical of K-files.

67. Hedströem file
Hedströem File: Design & Structure
• Hedströem files are manufactured from round steel wire by grinding.
• Hedstrom files have flutes which resemble successively triangles set one on
another.
• Hedstrom files cut only when instrument is withdrawn because its edges face
the handle of the instrument.
• When used in torquing motion, their edges can engage in the dentin of root
canal wall and causing H-files to fracture.
• Hedstrom files should be used to machine straight canals because they are
strong and aggressive cutters. Since they lack the flexibility and are fragile in
nature, the Hfiles tend to fracture when used in torquing action.
• Advantages of H-files
1. Better cutting efficiency 2. Push debris coronally
• Disadvantages of H-files
1. Lack flexibility 2. Tend to fracture 3. Aggressive cutter

68. Hedströem File: Sizes & Codes
Hedströems come in sizes 08 - 140, all with a taper of 0.02.

69. Hedströem File: Recommended use
• Hedströem can be used both in straight canals and curved canals.
• The hedströem prepares dentin effectively only when using a filing,
up and down motion.
• In curved canals, files (sizes 20/25 and bigger) must be pre-curved
to correspond to the shape of the curve.
• Hedströem files must always fit loosely in the canal to avoid risk for
fracture. Small sizes up to #25 can be used down into full
preparation length while bigger sizes are often used 1 - 3 mm short.

70. (B) -H-style modifications:
H-style file
1- Unifile
2- S-File
3- Safety H-File
4- NT-Sensor File
5- A-File
6- U-File

71. 1-Unifile:
1. It is the 1st. modification of H- files.
2. Designed with 2 spirals for cutting blades.
3. The double helix blade represent –S- shape in
cross section .
4. Unifile is huskier than the standard H- file and
cut more efficiently.

72. 2- S- file:
 It is a variation of the Unifile in its double helix
configuration and the variation in flutes depth and
pitch from tip to shaft.
3-Safty Hedstroem file
• It has non-cutting tip to prevent ledging in curved canal.
4-NT sensor files:
 It offers more cutting efficiency.

73. 5-A-file:
1. It has steep depth of the flutes and 40º helical angle of cutting blades
which cut more efficiently than H-File (70º).
2. It has non cutting tip.

74. ** The main advantage of A-file is its use in curved canals non-
cutting tip insures that the point will follow the canal lumen and will
not catch in the wall, starting a ledge or a perforation.
Inner
W
(1)
Outer
W
(2)
(3)

75. 6- U- file:
1. It has a triangular blade, but with 90º cutting edges
at each point of the triangular blade.
2. U-shaped adapts well to the curved canal,
aggressively planning the external wall while
avoiding the more dangerous internal wall where
perforation or stripping occurs.
3. This file is used in both push- pull and rotary
motion.

76. Stainless steel hand instruments: (A) barbed broach; (B) reamer; (C) K-
file; (D) Flexofile; E) Hedstrom file.

77. There are three major areas
of development of new files :
1. Increase the file flexibility
by changing the file metals.
2. Increase the file flexibility
and cutting efficiency by
changing the file design.
3. Modification of the file tip
to produce files doesn’t zip
or produce perforation by
flute removal or safety tip
design.
Modification of Intracanal Instruments:

78. Nickel-titanium instruments (NiTi)
• There have been a number of newer developments in
instrument design and technology. Instead of stainless
steel, nickel-titanium (NiTi) alloys have been introduced
in the manufacture of endodontic instruments.
• The NiTi alloys have many interesting properties:
1. Shape memory effect (ability to return perfectly to
its original shape)
2. Superelasticity (low modulus of elasticity),
3. Good biocompatibility
4. High corrosion resistance.

80. Nickel-titanium (NiTi)
NiTi File: Design & Structure
• NiTi files are manufactured from nickel-titanium.
• The angle between the long-axis and the cutting blade is bigger
than in reamers, and therefore preparation by NiTi file is effective
both in rotating motion and in filing motion (up and down
movement).
• The tip of the instrument is non-cutting which makes the
NiTiflex-file well suited for the preparation of curved canals
without the risk of ledge formation.

81. NiTi File: Sizes & Codes
• NiTiflex-files come in sizes 15 - 60, all with a taper of 0.02. K-file design is identified
by the square symbol on the handle.
• NiTiflex-files can be best distinguished from normal K-files by the code that in
NiTiflex-files is printed with two colours.

82. NiTi File: Recommended use
• NiTiflex-file is suited to be used both in straight
canals as well as in curved canals.
• The NiTiflex-file prepares dentin both in filing
motion (up and down) and when rotated.
• In curved canals the recommended techniques are
continuous rotation when the resistance is small
and balanced force against greater resistance.

83. Metals
Nickel-titanium Stainless steel
Excellent flexibility Less flexible
Conforms to canal
curvature
Straightens and transports
canal
Plastic deformation Permanent deformation

84. Metals
Stainless steel files demonstrate permanent deformation

85. Metals
Nickel-titanium files demonstrate plastic deformation

86. Power-assisted root canal instruments
Many different power-assisted root canal
instruments have been developed over the years
in the hope of making root canal preparation
quicker and to reduce operator fatigue.

87. More efficient flute design has less spirals
per unit length around the shaft thereby
decreasing stress concentration points
Limit number of rotations of the file in
the canal by decreasing its time
within the canal

89. Torque Control
• Predefined torque values are based on new
instruments!
• Used NiTi files have 50-60% decreased resistance to
fracture after use with high-torque motors. Gamborini
2001
• Predefined torque values on some motors are > than
the fracture limit of the NiTi file. Gamborini 2001

90. NiTi (Nickel titanium) rotary instruments
Function, features and directions for use
• Used to clean and shape the canals
• Used with endodontic handpiece and motor
• NiTi is flexible and instruments follow the canal
outline very well
• Several varieties of systems with different sequences
of instruments are used
• Important to follow the manufacturer’s recommended
speeds and instructions for use
Varieties
• Different lengths: 21 mm and 25 mm

92. Multiple Systems Available

93. First-generation Systems
• This generation of instruments in general, have passive cutting radial lands, which
helped a file to stay centered in the canal curvatures during work and fixed tapers of
4% and 6% over the length of their active blades.
• In addition, this generation of files have negative rake angles, which makes the file
passive; these instruments perform a scraping or burnishing rather than a real cutting
action, remove dentin slower, and have less of a tendency for canal straightening.
• This generation’s systems require numerous files for completing preparation of the
root canal, which was the major disadvantage.

94. Rotary NiTi instruments

95. Second-generation Systems
• The feature that distinguished this generation of instruments from the
first generation is that they have active cutting edges and thus
require fewer instruments to prepare a root canal.
• In general, active instruments cut more effectively and more
aggressively, and have a tendency to straighten the canal curvature.

96. Third-generation Systems
• Improvements in NiTi metallurgy became the hallmark of what may be considered
the third generation of mechanical shaping files.
• In 2007, some manufacturers began to focus on using heating and cooling
methods for the purpose of reducing cyclic fatigue, and improving safety
with rotary NiTi instruments in canals that are more curved. i.e., M-wire and
R-phase technology.
• This third generation of NiTi instruments significantly reduced cyclic fatigue
and consequently, less breakage of files occurred.

97. Fourth-generation Systems
• An advancement in canal preparation procedures was achieved with
reciprocation, a process that may be defined as any repetitive up-and-
down or back-and forth motion.
• Innovation in reciprocation technology led to a fourth generation of
instruments for shaping canals.
• This generation of instruments and its related technology have again
fuelled the hope for a single-file technique.
• The reciprocating movement allows a file to progress more readily,
cut efficiently, and remove debris from the canal effectively

98. Fourth-generation Systems

99. Fifth-generation Systems
• The latest generation of shaping files have been designed in such a
way that the center of mass or the center of rotation, or both are
offset.
• When in rotation, files that have an offset design produce a
mechanical wave of motion that travels along the active length
of the file.
• In addition, it enhances the removal of debris from a canal and
improves flexibility along the active portion of the file.
• This generation’s files have been recently introduced, adapting the
advantages from both the second and the third generations.