The document discusses a new paradigm in nickel-titanium (NiTi) instrumentation called the Self-Adjusting File (SAF) system. The SAF represents an improvement over traditional rotary NiTi files by adapting to the three-dimensional anatomy of the root canal, continuously irrigating during instrumentation, and requiring only a single file per canal. Studies have shown the SAF more effectively cleans and shapes canals while preventing issues like canal transportation compared to traditional rotary files. The simple SAF procedure and ability to respect root canal anatomy may provide more effective and higher quality root canal treatments.

2. A New Paradigm in NiTi Instrumentation Raviv Zary

3. Paradigm “ A framework of thoughts and concepts within which scientific experiments are performed”

4. The Introduction of Nickel-Titanium Rotary Instruments Represented a Paradigm Shift in Endodontics

5. Profile 1993 A Disruptive Technology

6. Evolution of Rotary NiTi Files Profile 1993 Quantec 1996 GT 1998 Hero642 1999 FlexMaster 2000 1 st Generation Symmetrical & Uniform

7. Evolution of Rotary NiTi Files Race 1999 ProTaper 2001 K3 2001 Hero Shaper 2002 Revo-S 2009 2nd Generation Asymmetrical and/or Not Uniform

8. Evolution of Rotary NiTi Files 3rd Generation GT - X 2009 M Wire TF 2009 R Phase Innovative Metallurgy

9. Motorized instrumentation Faster instrumentation Able to negotiate curved canals Great Technology !

10. Nevertheless Rotaries are Rotaries are Rotaries …

11. Common to all : Many instruments Complicated sequences Tedious repeated rinsing is essential

12. Common to all : Instruments break unexpectedly Separated apical part is difficult to remove A Major Drawback !

13. Common to all : Ignoring the 3D shape of the root canals !

14. The Common Misconception Dentists tend to relate to all root canals as if they had a uniform round cross section

15. This is true in upper incisors but wrong in many other teeth

16. Oval or flat canals are common in lower incisors canines premolars distal roots of lower molars

18. Canals with “ tear-shaped” cross section are common in premolars mesial roots of lower molars mesio-buccal roots of upper molars

19. All appear the same on a 2D X-ray

20. Current High-End Technology Rotating Blade with Flutes

21. All root canals are machined to a round cross section

22. Root Canals with a Tear-Shaped Cross-Section

23. Treated with Rotary Nickel Titanium Files Flat Canals * * Will look great on the radiograph

24. Treated with Rotary Nickel Titanium Files Canals with a “ Tear-Shaped” Cross Section * * Will look great on the radiograph

25. Do We Aim for Nice Radiographs or High Quality Endodontic Treatment ?

26. This may explain the frequently encountered enigma : Endodontic failures in roots with apparently good root canal fillings * * Misleading 2D X-Ray images

27. Wu & Wesselink, Int Endod J 34: 137-141, 2001

28. De Deus et al. Int Endod J 41: 183-190, 2008

29. De Deus et al. J Endod 34: 1401-1405, 2008

30. Micro CT Analysis B12 Rotary File

31. Bucco-Lingual B12 Rotary File Mesio-Distal

32. B12 Rotary File 2 mm 4 mm 6 mm

33. B53 Rotary File Micro CT Analysis Bucco-Lingual Mesio-Distal

34. 2 mm B53 Rotary File 2 mm 4 mm 6 mm

35. J Endod 35: 1044-1047, 2009 Hard Tissue Debris Accumulation Analysis by High Resolution Computed Tomography Scans Paqué et al 2009 New Insight !

36. Packing of Debris into the Isthmus Area During Rotary Instrumentation

37. The Longitudinal 3D challenge Curved Canals

38. Int Endod J 36: 86-92, 2003 ProTaper Rotary Root Canal Preparation: Effects of Canal Anatomy on Final Shape Analyzed by Micro CT Peters et al 2003 3 D X-Ray

39. Peters et al 2003 Superimposed Images Red : Surface untouched by file Green : Affected surface Clear : Final preparation

40. Percent of Root Canal Surface Unchanged by the File Int Endod J 36: 86-92, 2003 Peters et al 2003 Disto-buccal (n=11) 33 (±19)% Mesio-buccal (n=11) 43 (±29)% Palatal (n=11) 49 (±29)%

41. Paqué et al 2009 ProFile ProTaper Flexmaster Lightspeed GT NiTi K File Percent Untreated Root Canal Surface Adapted from: Paqué et al J Endod 35:1056-9, 2009 Can we do Better ?

42. Peters et al. Int Endod J 2003, 36:86-92 Canal Transportation* (µm) & Canal Straightening (%) in Upper Molars * CM shift

43. (2) Peters et al. Int Endod J 2003, 36:86-92 Canal Transportation* (µm) P MB DB * CM shift Can we do better ?

44. (2) Peters et al, Int Endod J 2003, 36:86-92 Canal Straightening (%) P MB DB Can we do better ?

45. NiTi Rotary Files Resulted in a Great Progress in Endodontics

46. Which Frontiers Still Remain to be Engaged ?

47. Many instruments Complicated Sequences

48. Unexpected instrument separation

49. Flat oval root canals Canal transportation Curved root canals

50. Need for effective irrigation

51. These Call for Out-of-the-Box Thinking

52. Paradigm Shift in Canal Instrumentation

53. A New Concept SAF System

54. A Self Adjusting File SAF System Operated by a Vibrating Handpiece Made of NiTi

55. The hollow file is used with continuous irrigation

56. Cleaning & Shaping and Irrigation are Achieved Simultaneously

57. SAF System A New Concept A Compressible File 1

58. A hollow, compressible file

59. SAF Adapted into a # 20 K File Path

60. SAF System A New Concept A File Which Adapts Itself to the Canal’s 3D Anatomy 2

61. Adaptation to Longitudinal Curvature

62. Mandibular Incisor Adaptation to Oval Cross Section

63. SAF System Circumferential Removal of Dentin 3 A New Concept

64. Sand Paper Rough Surface Pressure Repeated Motion

65. Roughness : 2.8 µm ± 10%

66. The vibrating hand-piece provides 5000 vibrations per min + Pecking Motion

67. Goal attained with a minimal and uniform wall thickness reduction !

68. SAF Current Nickel Titanium Rotary Files Flat Canals

69. Current Nickel Titanium Rotary Files SAF Canals with a “ Tear-Shaped ” Cross Section

70. Micro CT Analysis Red : before treatment Blue over red : after 4 min treatment G93

71. Micro CT Analysis Red : before treatment Blue over red : after 4 min treatment A 32

72. Cross section at 6 mm from the apex A 32

73. An Extreme Case C-Shaped Canal

74. 2 nd Lower Molar TLS 16

75. 0° - 45° - 180° 90° 45° TLS 16 1 mm

76. SAF preparation 0° - 40° - 120° - 80° 120° 80° 40° Green: before preparation Red: after preparation 1 mm

77. Cross Sections 4mm 2mm Distance from the apex

78. Distal Roots of Lower Molars Paqué et al J Endod 36:703-707, 2010 ProTaper – Manufacturer’s Instructions 79.9 (±10.3)% Untreated

79. Distal Roots of Lower Molars ProTaper Circumferential Filing 69.1 (±9.2)% Untreated Paqué et al J Endod 36:703-707, 2010

80. Distal Roots of Lower Molars SAF System 23.5 ( ± 8.9)% Untreated

81. SAF System Prevention of Canal Transportation 4 A New Concept

82. Micro CT Analysis A 22

83. Paqué et al 2009 SAF Current Study ProFile ProTaper Flexmaster Lightspeed GT NiTi K File Percent Untreated Root Canal Surface Adapted from: Paqué et al J Endod 35:1056-9, 2009

84. (1) (2) (1) Peters et al, Int Endod J 2003, 36:86-92 (2) Metzger et al, on-going study Canal Transportation* (µm) P MB DB * CM shift

85. (1) (2) (1) Peters et al, Int Endod J 2003, 36:86-92 (2) Metzger et al , on-going study Canal Straightening (%) P MB DB

86. SAF System Continuous Irrigation with Sodium Hypochlorite 5 A New Concept

87. Irrigator Attachment Hollow File

88. LCD Display Flow Control Buttons Foot Switch SAF System Irrigator VATEA ©

89. Irrigation Solution Reservoir 400 ml SAF Sytem Irrigator VATEA

90. Flow Rate 1-10 mL / min = 4 - 40 mL in 4 min

91. Positive Pressure Irrigation Negative Pressure Irrigation vs No-Pressure Irrigation

92. Will the solution flow beyond the apex ?

93. Rinsing efficacy : Transparent Blocks

95. Exchange of Irrigant

96. Rinsing Scrubbing

97. SAF System Continuous No-Pressure Irrigation with Activation & Scrubbing

98. Cleaning the root canal SEM Study

99. SAF Cleaning and shaping with NaOCl 3% alternating with EDTA 17% SEM

100. Smear Layer Scoring (Hülsmann 1997) Score 1 No smear layer, dentinal tubules open. Score 2 Small amount of smear layer, some dentinal tubules open. Score 3 Homogenous smear layer, only few dentinal tubules open. Score 4 Complete root canal covered, no open dentinal tubules. Score 5 Heavy, non homogenous smear layer covering the complete root canal wall. X 1000

101. Debris Scoring (Hülsmann 1997) Score 1 Clean root canal wall, few small debris particles. Score 2 Few small agglomerations of debris. Score 3 Many agglomerations of debris covering less than 50% of root canal wall. Score 4 More than 50% of root canal covered by debris. Score 5 Complete or nearly complete root canal wall covered by debris. X 200

102. Apical Mid-Root Coronal D75 X 500 Apical

103. Apical Mid-Root Coronal D75 X 200 Apical

104. Apical Mid-Root Coronal F48 X 1000 Apical

105. Canal Wall Free of Debris Coronal Third Middle Third Apical Third 20/20 100% 20/20 100% 20/20 100% Metzger et al, J Endod 36:697-702, 2010

106. Canal Wall Free of Smear Layer Coronal Third Middle Third Apical Third 20/20 100% 16/20 80% 13/20 65% Metzger et al, J Endod 36:697-702, 2010

107. SAF System High Durability : No File Separation 6 A New Concept

108. Torque Durability Separation after ~ 1.3 turns Rotary file

109. Torque Durability Separation after ~ 3.5 turns SAF

110. Mechanical Failure Patterns

111. Mechanical Failure Patterns

112. The SAF Procedure

113. The SAF Procedure Orifice funneled Irrigating while working One instrument ! Path established up to # 20

114. SAF – Benefits = H igher quality of treatment Improved cleaning Improved irrigation Improved sealing Improved preservation of canal walls

115. SAF – Benefits A simple armamentarium

116. S 16/21 mm M 18/25 mm L 21/31 mm Ø 1.5 mm One File Per Procedure

117. SAF – Benefits A simple, easy procedure = Short learning curve A simple armamentarium

118. SAF – Benefits A simple, easy procedure A simple armamentarium Improved Safety !

119. Obturation Methods

120. A New Method for Evaluation of Root Canal Filling– Dentin Contact by 3D Micro CT Analysis Resolution:17 µm

121. RCF- Dentin Contact – 98% Scan after Treatment + Scan after Obturation Yellow : touched by the RCF Red : un-touched by the RCF Resolution:17 µm

122. Tooth A22 - Lateral Compaction Bucco-lingual Mesio-distal

123. RCF / Dentin contact – 89.6% Tooth A22 - Lateral Compaction

124. Tooth A04 – Heated Gutta-Percha Injection Bucco-lingual Mesio-distal

125. RCF / Dentin contact – 98.6% Tooth A04 – Heated Gutta-Percha Injection

126. Bucco-lingual Mesio-distal Tooth A60 - Thermafil

127. RCF- Dentin Contact – 90% Tooth A60 - Thermafil

128. Obturation Study

129. Obturation Study % canal wall affected by the file Red: Area unaffected by the file

130. Obturation Study % canal wall touched by the root canal filling Yellow: Area untouched by the RCF

131. Figure 3 Correlation between % Unaffected Canal Wall and % untouched by RCF )

132. 2009: Clinical Trials

133. March 2010 >250 Clinical Cases

134. * * * * * * *

135. Conclusion

136. The SAF System Represents A Paradigm Shift In NiTi Instrumentation

137. Journal of Endodontics April 2010 The Self Adjusting File (SAF). Part 1: Respecting the Root Canal Anatomy A New Concept of Endodontic Files and Its Implementation Metzger Z, Teperovich E, Zary R, Cohen R, Hof R J Endod 36:679-690, 2010

138. Journal of Endodontics April 2010 The Self-Adjusting File. Part 2: Mechanical Analysis Hof R, Perevalov V, Eltanany M, Zary R, Metzger Z J Endod 36:691-696, 2010

139. Journal of Endodontics April 2010 The Self-Adjusting File (SAF). Part 3: Removal of Debris and Smear Layer A Scanning Electron Microscope Study Metzger Z, Teperovich E, Cohen R, Zary R, Paqué F, Hülsmann M J Endod 36:697-702, 2010

140. Thank You Raviv Zary [email_address]