4th year lecture recent advances in automation of endodontic instrumentation (Rotary & Reciprocating instruments)

1. ashraf_refai@hotmail.com
Ashraf
Refai
Samir
BDS MSc DD HMD • Professor & Former Head of
Department of Endodontics
@ Al-Azhar University -
Cairo - Egypt
• Micro-Endodontist since
2009
• Visiting Professor FUE &
MIU
• Owner & Founder of
Integrated Dental Clinic
www.arefai.edublogs.org
www.idclinics.net

2. Recent Advances in
Instrumentation Techniques
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Dr. Ashraf S. Refai
Professor of Endodontics
Al-Azhar University

3. Lecture
Title
Wake up Call…
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4. What is Conventional???
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5. Components of a Preparation
Technique (System of Preparation)
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6. Step Back
Step Down or Crown Down
Hybrid Techniques
Directions…
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7. Step Back
Technique
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8. Step Down or Crown Down
Techniques
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9. Hybrid???
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10. Endodontic instruments are currently made out
of either stainless steel or nickel titanium
alloy
Quick Reminder…
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11. NiTi Structure

12. Heat Treated NiTi...
M-wire
R-Phase Alloy
CM-Wire

13. Advantages of Heat
Treated Niti...
• More Flexible
• More resistant to cyclic
fatigue

14. The Restoring Force of
Files

17. What is wrong with Conventional files?
Why the Hype?
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18. Disadvantages
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Time
Consuming
Occupational
Hazards
Standardizatio
n
Curved Canals
Iatrogenic
Errors
Debris
Extrusion

19. Crown Down
Vs Step Back
Apically
Extruded Debris
Less Stress
on Files
Reservoir of
Irrigant
Reduced
Curvature

20. Endodontic Advancement
Timeline
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1900’s
Use of
stainless steel
rotary
instruments
1970-80
Revival of use of
stainless steel rotary
instruments
1988
Walia et al.
uses first
manual Niti
instruments
1950-60
Discovery of Niti Alloy 1990’s
Combination of
Rotary & Niti
technology
To Date
Development
of different
Rotary Niti
?

21. The First Rotary Niti
Instruments...
Lightspeed
Profile
GT Rotary
1992-1994

22. The Radial Lands & The
Symmetrical Cross
Section...

23. The Constant Taper,
Pitch & Helical Angle ...

24. Drawbacks of the
1st Generation
Instruments
• High incidence of
instruments separation
• Low cutting efficiency
• Screw in (Taper Lock)
• Large number of
instruments
Berutti E, Chiandussi G, Gaviglio I, Ibba A. analysis of torsional and bending stresses in two mathematical models of nickel-titanium
rotary instruments: ProTaper versus ProFile.J Endod. 2003 Jan;29(1):15-9.
Berutti E, Negro AR, Lendini M, Pasqualini D (2004) Influence of manual preflaring and torque on the failure rate of ProTaper rotary
instruments. Journal of Endodontics 30, 228–30.

25. More First Generation
Instruments
Hero 642
Quantec
1997-2000

26. Changes in Design
Features
• Positive rake angles
(Sharp Cutting Edges)
• Atypical cross-sections
• Variable pitch and helical angle

27. 2nd Generation Instruments...
K3
ProTaper
2000-2007
Revo S
RACE

28. Design Features of
2nd Generation Instruments
• Variable taper
• Improved manufacturing
• Specific instrument sequences
• Changes in the file numbering & naming system
• Reduction of the number of files in the sequence

29. Heat Treated NiTi & Altered Niti
Alloys…
• M-wire • R-phase alloy • CM wire
2007

30. Advantages of Heat Treated
Niti & Altered Niti
Instruments…
• More Flexible
• More resistant to cyclic
• Some even allow for plastic
deformation

31. GTX
ProTaper
Gold
2008
Hyflex
CM
Twisted
File
M-Two
Heat Treated Niti & Surface treated
Instruments
ProTaper
Next

32. State of The
Endodontic Community
in 2008
• Many types of Rotary systems
• Endodontists looking for system with
least number of files & Possibility of
separation
• Pretty much been the same for about 5
years
• No major breakthroughs or changes

33. One File Endodontics...
Yared G. Canal preparation using only one Ni-Ti rotary instrument: preliminary
observations. Int Endod J 2008;41:339–44.
2008

34. Balanced vs Unbalanced
Reciprocation
Balanced Un-Balanced
60°
60° 150°
30°

35. 21(0.6)
25 (0.8)
40 (0.8)

36. #25(0.8)
#40(0.6)
#50(0.5)

38. Advantages of a One
File Reciprocating
System
• Reduce the overall treatment time
• Increased cyclic fatigue resistance and reduced potential of
torsional fracture
• No risk of cross contamination
• Simplification of the shaping procedures

39. Has a variable taper
Triangular cross-section
looks like a modified K-
File
No radial lands
Some of the instruments
have a partially active tip
while others have a non-
cutting tip
High torque 150-300
RPM
Comes in 6 Sizes
SX, S1, S2, F1, F2, F3
ProTaper Instrument
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40. www.arefai.edublogs.org
Tip Size:
0.19
Reduction in
Taper

41. www.arefai.edublogs.org
S1 Tip Size:
0.185
S2 Tip Size: 0.20
Variable Taper
Increase along
the length of the
file

42. www.arefai.edublogs.org
F1 Tip Size: 0.20
F2 Tip Size: 0.25
F3 Tip Size: 0.30
Taper Between D1-D3: F1 (0.7), F2 (0.8), F3 (0.9)

44. Questions…
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45. Guidelines When Using Rotary
NiTi Instruments
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Guideline #1
You Should always have SLA
(Straight Line Access)

46. Guidelines When Using Rotary
NiTi Instruments
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Guideline #2
Must create a glide path
(Minimum size #15)

47. Guidelines When Using Rotary
NiTi Instruments
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Guideline #3
Be familiar with the canal anatomy
(Curves, recures etc…)

48. Guidelines When Using Rotary
NiTi Instruments
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Guideline #4
NEVER SKIP FILES!!!
(Use files at recommended speed & torque)

49. Guidelines When Using Rotary
NiTi Instruments
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Guideline #5
Use frequent &
copious irrigation

50. Guidelines When Using Rotary
NiTi Instruments
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Guideline #6
Use minimal pressure
(Just enough not to break a pencil tip)
‘Take what the canal gives you don’t force
the instrument’

52. Guidelines When Using Rotary
NiTi Instruments
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Guideline #7
Insert & remove instruments while they are
rotating
‘The instrument should be constantly
moving using an in & out motion’

53. Guidelines When Using Rotary
NiTi Instruments
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Guideline #8
Don’t overuse the instruments
‘Most manufacturers suggest a single use
of the instrument’

54. SLA
Glide path
Be familiar with the
canal anatomy
Never skip Files
Use copious & frequent
irrigation
Use minimal pressure
Insert & remove the
instrument while it is
rotating
Don’t overuse the
instruments
Guidelines Review
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55. Torque
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57. Thank you for your attention…
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