The document discusses various endodontic instruments used for root canal treatment. It describes the evolution of endodontic instruments from crude early designs to modern specialized instruments. It provides classifications of endodontic instruments and details various instruments, including their design, sizes, recommended usage techniques, and safety tips. Instrument types discussed include files, reamers, broaches, spreaders, and pluggers. The document also covers standardization of instrument sizes and tapers over time.

2.  In considering the endodontic instruments those that are hand
operated are the most important.
 However other specialised instruments such as explorers &
excavators have been designed to adapt to the root canal
treatment requirement.
 Originally instrument for root canal treatment were few in
number and crude in design.
 The earliest hand operative devices had long handles that were
best suited for anterior teeth.
 As RCT diversified, small “finger” instruments were developed for
posterior teeth.
 New designs in endodontics instruments have been introduced
and will continue to evolve.

3. MICRO
INSTRUMENTS
INTRACANAL
INSTRUMENTS
GENERAL
INSTRUMENTS
Classification

4.  1) Front surface mouth mirror

5.  2) Periodontal probe

6.  3) Explorer

7.  4) Cotton forceps

8.  5) Endodontic explorers
DG 16
DG 16/23

9.  6) Endodontic excavator

10.  7) Endodontic ruler

11. 8) Instrument organizer (endodontic kit)
 used for arrangement of reamers and files
according to the size and length.
 provides holes for the files to be place
vertically in a sponge which is saturated with
disinfectant to maintain its sterility.

12. 9) Endodontic syringe
 tip of the instrument is flat to prevent penetration of
the needle to the small canals;
 also it has a groove in its tip to permit the irrigation
which might be under pressure to flow coronally
rather than forcing it to the apical foramen causing
post operative pain.

13. 10) Transfer sponge

14. A-Carbon steel-
contain less than 2.1% of
carbon
 Have high hardness than SS
instruments.
 Prone to corrosion, so cant be
re-sterilised.
 Prone to rust.
 Example: barbed broch
B-Stainless steel instruments-
contain 18% chromium, 8-
10% nickel, 0.12% carbon
 Corrosion resistant
 Stiff nature
 Prone to fracture
 Prone to distortion

15. C-Nickel titanium - contain 55% Ni and 45% Ti
 Shape memory
 Super elasticity
 Low modulus of elasticity
 Corrosion resisitant
 Softer
 Good resilience
 Biocompatibility
 Poor cutting efficiency
 Don’t show signs of fatigue before they fracture
 Poor resistance to fracture.

16. 1-Broaches & Rasps:
 Made from round stainless steel wire blank.
 Working edges are created by cutting into the wire at an
angle to its long axis.
 The depth angle and number of cuts (barbs) will determine
how the instrument is used

17. 2- K Files & reamers:
 Designed in 1904 by Kerr Manufacturing Co.
 Are the most widely copied and extensively manufactured endodontic
instruments worldwide .
 Previously made of Carbon Steel Presently made of Stainless Steel.
 K File and Reamer are the oldest instruments used to machine dentin.
 Produced by grinding graduated sizes of round Piano wire into either a
square or triangular configuration
 These instruments are useful for penetrating and enlarging root
canals.
 These instruments works primarily by compression and release
destruction of the dentin surrounding the canal.

18. Design & structure
 Made from triangular
blanks.
 More flexible.
 The helix angle is small,
therefore effective only in
rotating motion
 Has cutting tip
 0.5-1 flute/mm.

19. Reamer: Sizes & Codes
 comes in sizes 06 -
140,
 all with a taper of 0.02.
 design is identified by
the triangle symbol on
the handle.

20. Reamer: Recommended use
 It is used by continuous
rotation when the resistance
is small or moderate
 and by balanced force when
the resistance is greater.
 In curved canals ledging
easily occurs with even small
reamer sizes if instruments
are not pre-curved.

21. Reamer: Safety tips
 Reamers can be rotated only using
moderate pressure.
 Use of force, particularly with
smaller sized instruments, may
result in distortion of the helical
structure and ultimately in fracture.
 Each instrument should be checked
for symmetry by rotating it against
an even background before
introducing it into the canal.

22. K-file: Design & Structure
 Made from rectangular blanks
 Helix angle is greater than in a
reamer, and therefore preparation
by a K-file is effective both in
rotary and filing motion.
 The tip of the instrument is cutting
 less flexible than reamers but are
more effective in cutting.
 1.5-2.25 flute/mm.

23. K-file: Sizes & Codes
 K-files are produced in sizes
06 - 140,
 all with a taper of 0.02.
 K-file design is identified by
the square symbol on the
handle.

24. K-file: Recommended use
 It prepares both in filing motion (up and
down) and when rotated.
 In slightly curved canals -continuous
rotation when the resistance is small and
balanced force against greater resistance.
 Compared to reamers, the use of
continuous rotation is limited because of
the screwing effect typical of K-file.

25. K-file: Safety tips
 K-files can be rotated only using moderate
pressure.
 Use of force, particularly with smaller sized
instruments may result in distortion of the helical
structure and ultimately in fracture.
 Balanced force technique and filing instead of
continuous rotation should be used with sizes 06 -
15 to minimize fracture risk.
 Each instrument should be checked for symmetry
by rotating it against an even background before
introducing it into the canal

26. Flexoreamer: Design & Structure
 manufactured from a triangular
steel wire that is twisted to give
the typical shape of a reamer.
 The helix angle is small, and
therefore 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.

27. Flexoreamer: Sizes & Codes
 come in sizes 15 – 40.
 all with a taper of 0.02.
 Flexoreamers are best
distinguished from normal
reamers by the size code at the
top of the instrument: in
flexoreamers the colour of the
number is the same as the
colour of the handle.

28. Flexoreamer: Recommended use
 The flexoreamer is well suited both
for straight canals and slightly
curved canals.
 It prepares dentin in rotation but not
if used as a file.
 The cutting efficiency and usability of
flexoreamers are excellent.
 In slightly curved canals the
recommended technique sare
continuous rotation when the
resistance is small and balanced
force against greater resistance.

29. Flexoreamer: Safety tips
 Flexoreamers can be rotated only using
moderate pressure.
 Use of force, particularly with smaller
sized instruments, may result in
distortion of the helical structure and
ultimately in fracture.
 Every instrument should be checked for
symmetry by rotating itagainst an even
background before introducing it into
the canal

30. FlexoFile: Design & Structure

31. FlexoFile: Sizes & Codes

32. FlexoFile: Recommended use
 Flexofile is suited for both straight
canals and slightly curved canals.
 Effective both in filing motion(up and
down) and when rotated.
 In slightly curved canals the
recommended techniques are
continuous rotation when the
resistance is small and balanced force
against greater resistance.
 Use of continuous rotation is limited as
compared to reamers because of the
screwing effect typical of K-files

33. FlexoFile: Safety tips
 Flexofiles can be rotated (balanced
force) only using moderate pressure.
 Use of force, particularly with smaller
sized instruments, may result in
distortion of the helical structure and
ultimately in fracture.
 Every instrument should be checked
for symmetry by rotating it against an
even background before introducing it
into the canal

34. Hedstrom File: Design & Structure
 Manufactured from round steel wire by
grinding.
 The helix angle is close to right angle,
which is therefore preparation by H files
is effective only when using a filing
motion (up and down movement).
 More positive rake angle.
 blade with a cutting rather than a
scraping angle

35. Hedstrom File: Sizes & Codes
 come in sizes 08 – 140.
 all with a taper of 0.02.
 H-file design is identified by
the circle symbol on the
handle.

36. Hedstrom File: Recommended use
 can be used both in straight canals
and curved canals.
 Cut only in retraction.
 In curved canals, files (sizes 20/25
and bigger) must be pre-curved to
correspond to the shape of the
curve.
 H-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.

37. Hedstroem File: Safety tips
 Hedstrom files show a greater risk for
fracture than reamers and K-files if
used in a wrong way.
 Hedstrom must always fit loosely in
the canal and they must never be
rotated.
 In curved canals Hedstrom-files are
pre-curved to correspond to the
shape of the canal.
 Before introducing them into the
canal, all Hedstrom files must be
inspected for possible earlier damage
to the instrument and discarded
immediately if an asymmetry in the
cutting area is found

38.  Rhomboidal or Diamond shaped
 This new cross-section presents
significant changes in instrument
flexibility and cutting
characteristics
 The cutting edges of the high
flutes are formed by the two
acute angles of the rhombus and
present increased sharpness and
cutting efficiency
 The alternating low flutes formed
by the obtuse angles of the
rhombus are meant to act as an
auger, providing more area for
increased debris removal

39.  They are made up of SS
 A hybrid instrument.
 More flutes than reamer but fewer than
K-file.
 Made from triangular stainless steel
blank by twisting, not ground.
 More aggressive & flexible than regular
K-style instrument.

40.  Made by removing the sharp
cutting edges from the tip of
instrument.
 Have non cutting tip, so less
chances of ledge formation,
canal transportation when used
with balance force technique.
 Triangular cross section which
provides it flexibility
 Made up of NiTi and cut during
anticlockwise rotary motion.

41.  Has noncutting safety side
along the length of the blade
which reduces the chances of
perforation.
 The noncutting side is directed
to the side of canal where
cutting is not required.
 Therefore prevents ledging of
the canals

42.  It is called S because of its cross-
sectional shape.
 Produced by grinding, which
makes it stiffer than H file.
 The file is designed with 2 spirals
for cutting blades, forming double
helix design.
 It has good cutting efficiency in
either filing or reaming action,
thus file can also be classified as
hybrid design.

43.  Used for difficult and calcified canals.
 Have better buckling resistance
than k files.
 Available in size 8, 10, 15 of length
18, 21 and 25 mm.

44.  Were described by Weine.
 Comes under intermediate files provided with
half sizes between conventional instruments.
 Available in sizes from 12-37 like 12, 17, 22,
27, 32, 37.
 Used for narrow canals.
 They are formed by cutting 1 mm from tip of
instrument.

45. In 1959, a new line of standardized instruments and filling
material was introduced by ingle and levine
 A formula for the diameter and taper in each size of
instrument and filling material was agreed on.
 A formula for a graduated increment in size from one
instrument to the next was developed.
 A new instrument numbering system based on
instrument metric diameter was established.

46. After the introduction of standardized instruments, about the
only changes made were
 the universal use of stainless rather than carbon steel
 the addition of smaller (Nos. 6 and 8) and larger (Nos. 110-
150) sizes as well as color coding.
It was not until 1976 that the first approved specification for
root canal instruments was published (ADA Specification No.
28)

47.  The numbering system, last revised in
2002, using numbers from 6 to 140, is
based on the diameter of the
instruments in hundredths of a
millimeter at the beginning of the tip of
the blades, a point called D0 (diameter
1 mm) , and extending up the blades
to the most coronal part of the cutting
edge at D16 (diameter 2-16 mm in
length).
 Additional revisions are under way to
cover instruments constructed with
new materials, designs, and tapers
greater than 0.02 mm/m

48.  Instruments with a taper greater than
the ISO (International Standards
Organization) standard of 0.02 mm/mm
have become popular: 0.04, 0.06, 0.08,
0.10, and 0.12.
 This means that for every millimeter
gain in the length of the cutting blade,
the width (taper) of the instrument
increases in size by 0.04, 0.06, 0.08,
0.10, or 0.12 of a millimeter rather than
the ISO standard of 0.02 mm/mm.
 These new instruments allow for
greater coronal flaring than the 0.02
instrument

49. comes in three lengths:
 standard, 25 mm;
 long, 31 mm; and
 short, 21 mm.

50. Taper
 usually is expressed as the amount
the file diameter increases each
millimeter along its working surface
from the tip toward the file handle.
Flute
 It is the groove in the working
surface used to collect soft tissue
and debris

51. Leading (cutting) edge
 The surface with the greatest
diameter that follows the groove
(where the flute and land
intersect) as it rotates.
.

52. land (marginal width)
 If a surface projects
axially from the central
axis as far as the cutting
edge between flutes

53. Relief
o To reduce frictional resistance,
some of the surface area of the
land that rotates against the canal
wall may be reduced to form the
relief.

54. Helix angle
 The angle the cutting
edge forms with the
long axis of the file

55. Rake angle
 angle formed by the
leading edge and the
radius of the file.

56. cutting angle/effective rake angle
 is a better indication of a file’s cutting ability
 determined by measuring the angle formed by the
cutting (leading) edge and the radius when the file is
sectioned perpendicular to the cutting edge
 If the flutes of the file are symmetric, the rake angle
and the cutting angle are essentially the same.

57. Pitch
 The distance between a point on the leading edge and
the corresponding point on the adjacent leading edge, or
it may be the distance between corresponding points
within which the pattern is not repeated

58.  long, tapered and pointed end
instrument, -compress gutta
percha into the apex and
periphery of the prepared canal
and also towards the irregularity
of canals
 leaving a space for insertion of
auxiliary root canal filling material
cones.
 Pluggers have blunt or flat ended
tips.

59. M series plugger-spreaders
 double-ended long-handled
instruments
 Handles colour coded
Corresponds to standard
sizing and taper of K-type files
Finger held spreaders and
condensers
 similar to K-type files with
plastic or metal handles.

60.  Instruments have been designed to take full advantage
of the increased visibility obtained with dental operating
microscopes, endoscopes, and orascopes.
 Better visualization of the surgical site would have
limited value without microsurgical instruments such as
ultrasonic tips for root-end preparation and micro-
mirrors for inspecting the root end.

62. 1- micro-mirrors
 Small round
 Medium oval

63. 2-Retractor
 Care must be taken
to rest the retractors
only on bone, not on
the reflected soft-
tissue flap or on the
neurovascular
bundle

64. 3-Elevator
4-Curette
 Jacquette
 spoon
Rubinstein Mini-Molt

65. 5-Scaler
6-Surgical forceps

66. 1-Castroviejo needle
holder
2-Castroviejo scissor

67. 3- microcondenser & plugger

68. 4-Messing gun type syringe

69. 5-Plugger with teflon sleeve

70. 6- Another delivery system designed specifically for MTA
placement. Kit includes a variety of tips for use in different
areas of the mouth and a single-use Teflon plunger.

71. 7- Hard plastic block with notches of varying shapes and sizes MTA is
mixed on a glass slab to the consistency of wet sand and then packed
into a notch. The applicator instrument is used to transfer the
preformed plug of MTA from the block to the root end.

72.  Current NiTi hand preparation procedures that use files with a
greater or variable taper are a substantial improvement over
instrumentation with 0.02 tapered stainless steel files
particularly when used in curved root canals.
 These newer instruments should produce canals with a better
shape, using fewer instruments in a shorter time.
 Microsurgical instruments such as ultrasonic tips for root-end
preparation and micro-mirrors for inspecting the root end
enhances better visualization and contributed to rapid
development of peri-radicular surgery.