Journal of Endodontics
Volume 30, Issue 8 , Pages 559-567 , August 2004

Current Challenges and Concepts in the Preparation of Root Canal Systems: A Review

References 

  1. Al-Omari MA , Dummer PM , Newcombe RG , Doller R . Comparison of six files to prepare simulated root canals. Part 2 . Int Endod J . 1992;25:67–81
  2. Nagy CD , Bartha K , Bernath M , Verdes E , Szabo J . The effect of root canal morphology on canal shape following instrumentation using different techniques . Int Endod J . 1997;30:133–140
  3. Peters OA , Peters CI , Schönenberger K , Barbakow F . ProTaper rotary root canal preparation: assessment of torque and force in relation to canal anatomy . Int Endod J . 2003;36:93–99
  4. Stropko J . Canal morphology of maxillary molars: clinical observations on canal configurations . J Endodon . 1999;25:446–450
  5. Cunningham CJ , Senia ES . A three-dimensional study of canal curvatures in the mesial roots of mandibular molars . J Endodon . 1992;18:294–300
  6. Hess W . Formation of root canals in human teeth . J Natl Dent Assoc . 1921;3:704–725
  7. Buhrley LJ , Barrows MJ , BeGole E , Wenckus CS . Effect of magnification locating the mb2 canal in maxillary molars . J Endodon . 2002;28:324–327
  8. Ida RD , Gutmann JL . Importance of anatomic variables in endodontic treatment outcomes: case report . Endod Dent Traumatol . 1995;11:199–203
  9. Siqueira JF , Araujo MCP . Histological evaluation of the effectiveness of five instrumentation techniques for cleaning the apical third of root canals . J Endodon . 1997;23:499–502
  10. Roane JB , Sabala CL , Duncanson MG . The “balanced force” concept for instrumentation of curved canals . J Endodon . 1985;11:203–211
  11. Kyomen SM , Caputo AA , White SN . Critical analysis of the balanced force technique in endodontics . J Endodon . 1994;20:332–337
  12. Wildey WL , Senia ES , Montgomery S . Another look at root canal instrumentation . Oral Surg Oral Med Oral Pathol . 1992;74:499–507
  13. Kartal N , Cimilli HK . The degrees and configurations of mesial canal curvatures of mandibular first molars . J Endodon . 1997;23:358–362
  14. Schneider SW . A comparison of canal preparations in straight and curved root canals . Oral Surg Oral Med Oral Pathol . 1971;32:271–275
  15. Pruett JP , Clement DJ , Carnes DL . Cyclic fatigue testing of nickel-titanium endodontic instruments . J Endodon . 1997;23:77–85
  16. Ruddle C . Cleaning and shaping the root canal system . In: Cohen S , Burns RC editor. Pathways of the pulp . 8th ed.. St. Louis: Mosby; 2002;p. 231–292
  17. Nagy CD , Szabo J , Szabo J . A mathematically based classification of root canal curvatures on natural human teeth . J Endodon . 1995;21:557–560
  18. Nagy CD , Keszthelyi G , Szabo J , Sulyok P , Ledeczky G , Szabo J . A computerized method for mathematical description of three-dimensional root canal axis . J Endodon . 2000;26:639–643
  19. Bjørndal L , Carlsen O , Thuesen G , Darvann T , Kreiborg S . External and internal macromorphology in 3D-reconstructed maxillary molars using computerized x-ray microtomography . Int Endod J . 1999;32:3–9
  20. Peters OA , Laib A , Rüegsegger P , Barbakow F . Three-dimensional analysis of root canal geometry using high resolution computed tomography . J Dent Res . 2000;79:1405–1409
  21. Peters OA , Schönenberger K , Laib A . Effects of four NiTi preparation techniques on root canal geometry assessed by micro computed tomography . Int Endod J . 2001;34:221–230
  22. Peters OA , Laib A , Göhring TN , Barbakow F . Changes in root canal geometry after preparation assessed by high-resolution computed tomography . J Endodon . 2001;27:1–6
  23. Peters OA , Peters CI , Schönenberger K , Barbakow F . ProTaper rotary root canal preparation: effects of canal anatomy on final shape analysed by micro CT . Int Endod J . 2003;36:86–92
  24. Hübscher W , Barbakow F , Peters OA . Root canal preparation with FlexMaster: canal shapes analysed by micro-computed tomography . Int Endod J . 2003;36:740–747
  25. Bergmans L , Van Cleynenbreugel J , Wevers M , Lambrechts P . A methodology for quantitative evaluation of root canal instrumentation using microcomputed tomography . Int Endod J . 2001;34:390–398
  26. Bergmans L , Van Cleynenbreugel J , Wevers M , Lambrechts P . Mechanical root canal preparation with NiTi rotary instruments: rationale, performance and safety. Status report for the American Journal of Dentistry . Am J Dent . 2001;14:324–333
  27. Gluskin AH , Brown DC , Buchanan LS . A reconstructed computerized tomographic comparison of Ni-Ti rotary GT files versus traditional instruments in canals shaped by novice operators . Int Endod J . 2001;34:476–484
  28. Rhodes JS , Pitt Ford TR , Lynch PJ , Liepins PJ , Curtis RV . A comparison of two nickel-titanium instrumentation techniques in teeth using microcomputed tomography . Int Endod J . 2000;33:279–285
  29. Rhodes JS , Ford TR , Lynch JA , Liepins PJ , Curtis RV . Micro-computed tomography: a new tool for experimental endodontology . Int Endod J . 1999;32:165–170
  30. Terakado M , Hashimoto K , Arai Y , Honda M , Sekiwa T , Sato H . Diagnostic imaging with newly developed ortho cubic-super-high resolution computed tomography (Ortho-CT) . Oral Surg Oral Med Oral Path Oral Radiol Endod . 2000;89:509–518
  31. Weine FS , Healey HJ , Gerstein H , Evanson L . Pre-curved files and incremental instrumentation for root canal enlargement . J Can Dent Assoc . 1970;36:155–157
  32. Powell SE , Simon JH , Maze BB . A comparison of the effect of modified and nonmodified instrument tips on apical canal configuration . J Endodon . 1986;12:293–300
  33. Dummer PM , Al-Omari MA , Bryant S . Comparison of the performance of four files with rounded tips during shaping of simulated root canals . J Endodon . 1998;24:364–371
  34. Griffiths IT , Bryant ST , Dummer PMH . Canal shapes produced sequentially during instrumentation with Quantec LX rotary nickel-titanium instruments: a study in simulated canals . Int Endod J . 2000;33:346–354
  35. Portenier I , Lutz F , Barbakow F . Preparation of the apical part of the root canal by the Lightspeed and step-back techniques . Int Endod J . 1998;31:103–111
  36. Al-Omari MA , Dummer PM , Newcombe RG . Comparison of six files to prepare simulated root canals. Part 1 . Int Endod J . 1992;25:57–66
  37. Endodontology ES . Undergraduate curriculum guidelines for endodontology . Int Endod J . 2001;34:574–580
  38. Weine FS , Kelly RF , Lio PJ . The effect of preparation procedures on original shape and on apical foramen shape . J Endodon . 1975;1:255–262
  39. Crump MC , Natkin E . Relationship of broken root canal instruments to endodontic case prognosis: a clinical investigation . J Am Dent Assoc . 1970;80:1341–1347
  40. Pettiette MT , Metzger Z , Phillips C , Trope M . Endodontic complications of root canal therapy performed by dental students with stainless-steel K-files and nickel-titanium hand files . J Endodon . 1999;25:230–234
  41. Pettiette MT , Delano EO , Trope M . Evaluation of success rate of endodontic treatment performed by students with stainless-steel K-files and nickel-titanium hand files . J Endodon . 2001;27:124–127
  42. Peters OA, Barbakow F, Peters CI. Nickel-titanium rotary root canal preparation: an analysis of 268 endodontically treated teeth. Int Endod J (in press).
  43. Thoden van Velzen SK , Duivenvoorden HJ , Schuurs AH . Probabilities of success and failure in endodontic treatment: a Bayesian approach . Oral Surg Oral Med Oral Pathol . 1981;52:85–90
  44. Lussi A , Messerli L , Hotz P , Grosrey J . A new non-instrumental technique for cleaning and filling root canals . Int Endod J . 1995;28:1–6
  45. Attin T , Buchalla W , Zirkel C , Lussi A . Clinical evaluation of the cleansing properties of the noninstrumental technique for cleaning root canals . Int Endod J . 2002;35:929–933
  46. Luiten DJ , Morgan LA , Baumgartner JC , Marshall JG . A comparison of four instrumentation techniques on apical canal transportation . J Endodon . 1995;1995:26–32
  47. Pertot WJ , Camps J , Damiani MG . Transportation of curved canals prepared with Canal Master-U, Canal Master- U-NiTi, and stainless steel K-type files . Oral Surg Oral Med Oral Path Oral Radiol Endod . 1995;79:504–509
  48. Jardine SJ , Gulabivala K . An in vitro comparison of canal preparation using two automated rotary nickel-titanium instrumentation techniques . Int Endod J . 2000;33:381–391
  49. Iqbal MK , Maggiore F , Suh B , Edwards KR , Kang J , Kim S . Comparison of apical transportation in four NI-Ti rotary instrumentation techniques . J Endodon . 2003;29:587–591
  50. Bramante CM , Berbert A , Borges RP . A methodology for evaluation of root canal instrumentation . J Endodon . 1987;13:243–245
  51. McCann JT , Keller DL , LaBounty GL . A modification of the muffle model system to study root canal morphology . J Endodon . 1990;16:114–115
  52. Tamse A , Pilo R . A new muffle model system to study root canal morphology and instrumentation techniques . J Endodon . 1998;24:540–542
  53. Kuttler S , Garala M , Perez R , Dorn SO . The endodontic cube: a system designed for evaluation of root canal anatomy and canal preparation . J Endodon . 2001;27:533–536
  54. Coleman CL , Svec TA . Analysis of Ni-Ti versus stainless steel instrumentation in resin simulated canals . J Endodon . 1997;23:232–235
  55. Short JA , Morgan LA , Baumgartner JC . A comparison of canal centering ability of four instrumentation techniques . J Endodon . 1997;23:503–507
  56. Shadid DB , Nicholls JI , Steiner JC . A comparison of curved canal transportation with balanced force versus Lightspeed . J Endodon . 1998;24:651–654
  57. Porto Carvalho LA , Bonetti I , Gagliardi Borges MA . A comparison of molar root canal preparation using stainless steel and nickel-titanium instruments . J Endodon . 1999;25:807–810
  58. Leseberg DA , Montgomery S . The effects of Canal Master, Flex-R, and K-Flex instrumentation on root canal configuration . J Endodon . 1991;17:59–65
  59. Kosa D , Marshall G , Baumgartner J . An analysis of canal centering using mechanical instrumentation techniques . J Endodon . 1999;25:441–445
  60. Deplazes P , Peters O , Barbakow F . Comparing apical preparations of root canals shaped by nickel-titanium rotary and nickel-titanium hand instruments . J Endodon . 2001;27:196–202
  61. Thompson SA , Dummer PM . Shaping ability of Lightspeed rotary nickel-titanium instruments in simulated root canals. Part 1 . J Endodon . 1997;23:698–702
  62. Thompson SA , Dummer PM . Shaping ability of Lightspeed rotary nickel-titanium instruments in simulated root canals. Part 2 . J Endodon . 1997;23:742–747
  63. Bryant ST , Thompson SA , Al-Omari MAO , Dummer PMH . Shaping ability of ProFile rotary nickel-titanium instruments with ISO sized tips in simulated root canals: part 1 . Int Endod J . 1998;31:275–281
  64. Bryant ST , Thompson SA , Al-Omari MAO , Dummer PMH . Shaping ability of ProFile rotary nickel-titanium instruments with ISO sized tips in simulated root canals: part 2 . Int Endod J . 1998;31:282–289
  65. Bryant ST , Dummer PM , Pitoni C , Bourba M , Moghal S . Shaping ability of .04 and .06 taper ProFile rotary nickel-titanium instruments in simulated root canals . Int Endod J . 1999;32:155–164
  66. Thompson SA , Dummer PM . Shaping ability of Hero 642 rotary nickel-titanium instruments in simulated root canals: part 2 . Int Endod J . 2000;33:255–261
  67. Thompson SA , Dummer PM . Shaping ability of Hero 642 rotary nickel-titanium instruments in simulated root canals: part 1 . Int Endod J . 2000;33:248–254
  68. Griffiths IT , Chassot AL , Nascimento MF , Bryant ST , Dummer PMH . Canal shapes produced sequentially during instrumentation with Quantec SC rotary nickel-titanium instruments: a study in simulated canals . Int Endod J . 2001;34:107–112
  69. Kum K-Y , Spångberg L , Cha BY , Il-Young J , Seung-Jong L , Chan-Young L . Shaping ability of three ProFile rotary instrumentation techniques in simulated resin root canals . J Endodon . 2000;26:719–723
  70. Al-Omari MA , Bryant S , Dummer PM . Comparison of two stainless steel files to shape simulated root canals . Int Endod J . 1997;30:35–45
  71. Bishop K , Dummer PM . A comparison of stainless steel Flexofiles and nickel-titanium NiTi Flex files during the shaping of simulated canals . Int Endod J . 1997;30:25–34
  72. Schäfer E . Shaping ability of Hero 642 rotary nickel-titanium instruments and stainless steel hand K-Flexofiles in simulated curved root canals . Oral Surg Oral Med Oral Pathol Oral Radiol Endod . 2001;92:215–220
  73. Schäfer E , Lohmann D . Efficiency of rotary nickel-titanium FlexMaster instruments compared with stainless steel hand K-Flexofile: part 1. Shaping ability in simulated curved canals . Int Endod J . 2002;35:505–513
  74. Schäfer E , Florek H . Efficiency of rotary nickel-titanium K3 instruments compared with stainless-steel hand K-Flexofile. Part 1. Shaping ability in simulated curved canals . Int Endod J . 2003;36:199–207
  75. Yun HH , Kim SK . A comparison of the shaping abilities of 4 nickel-titanium rotary instruments in simulated root canals . Oral Surg Oral Med Oral Pathol Oral Radiol Endod . 2003;95:228–233
  76. Hata G , Uemura M , Kato AS , Imura N , Novo NF , Toda T . A comparison of shaping ability using ProFile, GT file, and Flex-R endodontic instruments in simulated canals . J Endodon . 2002;28:316–321
  77. Ottosen S , Nicholls J , Steiner J . Comparison of instruments using Naviflex and ProFile nickel-titanium engine-driven rotary instruments . J Endodon . 1999;25:457–460
  78. Ponti TM , McDonald NJ , Kuttler S , Strassler HE , Dumsha TC . Canal-centering ability of two rotary file systems . J Endodon . 2002;28:283–286
  79. Garala M , Kuttler S , Hardigan P , Steiner-Carmi R , Dorn S . A comparison of the minimum canal wall thickness remaining following preparation using two nickel-titanium rotary systems . Int Endod J . 2003;36:636–642
  80. Tucker DM , Wenckus CS , Bentkover SK . Canal wall planning by engine-driven nickel-titanium instruments, compared with stainless-steel hand instrumentation . J Endodon . 1997;23:170–173
  81. Wu MK , Wesselink PR . A primary observation on the preparation and obturation of oval canals . Int Endod J . 2001;34:137–141
  82. Tan BT , Messer HH . The quality of apical canal preparation using hand and rotary instruments with specific criteria for enlargement based on initial apical file size . J Endodon . 2002;28:658–664
  83. Rödig T , Hülsmann M , Muhge M , Schäfers F . Quality of preparation of oval distal root canals in mandibular molars using nickel-titanium instruments . Int Endod J . 2002;35:919–928
  84. Weiger R , El Ayouti A , Löst C . Efficiency of hand and rotary instruments in shaping oval root canals . J Endodon . 2002;28:580–583
  85. Bergmans L , Van Cleynenbreugel J , Beullens M , Wevers M , Van Meerbeek B , Lambrechts P . Smooth flexible versus active tapered shaft design using NiTi rotary instruments . Int Endod J . 2002;35:820–828
  86. Bergmans L , Van Cleynenbreugel J , Beullens M , Wevers M , Van Meerbeek B , Lambrechts P . Progressive versus constant tapered shaft design using NiTi rotary instruments . Int Endod J . 2003;36:288–295
  87. Powell SE , Wong PD , Simon JH . A comparison of the effect of modified and nonmodified instrument tips on apical canal configuration. Part II . J Endodon . 1988;14:224–228
  88. Kuhn WG , Carnes DL , Clement DJ , Walker WA . Effect of tip design of nickel-titanium and stainless steel files on root canal preparation . J Endodon . 1997;23:735–738
  89. Hülsmann M , Schade M , Schäfers F . A comparative study of root canal preparation with HERO 642 and Quantec SC rotary Ni-Ti instruments . Int Endod J . 2001;34:538–546
  90. Hülsmann M , Herbst U , Schäfers F . Comparative study of root-canal preparation using Lightspeed and Quantec SC rotary NiTi instruments . Int Endod J . 2003;36:748–756
  91. Card SJ , Sigurdsson A , Ørstavik D , Trope M . The effectiveness of increased apical enlargement in reducing intracanal bacteria . J Endodon . 2002;28:779–783
  92. Hülsmann M , Gressmann G , Schäfers F . A comparative study of root canal preparation using FlexMaster and HERO 642 rotary Ni-Ti instruments . Int Endod J . 2003;36:358–366
  93. Schäfer E , Schlingemann R . Efficiency of rotary nickel-titanium K3 instruments compared with stainless steel hand K-Flexofile. Part 2. Cleaning effectiveness and shaping ability in severely curved root canals of extracted teeth . Int Endod J . 2003;36:208–217
  94. Lam TV , Lewis DJ . Changes in root canal morphology in simulated curved canals over-instrumented with a variety of stainless steel and nickel titanium files . Aust Dent J . 1999;44:12–19
  95. Blum JY , Cohen A , Machtou P , Micallef JP . Analysis of forces developed during mechanical preparation of extracted teeth using Profile NiTi rotary instruments . Int Endod J . 1999;32:24–31
  96. Sattapan B , Palamara JEA , Messer HH . Torque during canal instrumentation using rotary nickel-titanium files . J Endodon . 2000;26:156–160
  97. Hübscher W , Barbakow F , Peters OA . Root canal preparation with FlexMaster: assessment of torque and force in relation to canal anatomy . Int Endod J . 2003;36:883–890
  98. Peters OA , Barbakow F . Dynamic torque and apical forces of ProFile .04 rotary instruments during preparation of curved canals . Int Endod J . 2002;35:379–389
  99. Thompson SA . An overview of nickel-titanium alloys used in dentistry . Int Endod J . 2000;33:297–310
  100. Sattapan B , Nervo GJ , Palamara JEA , Messer HH . Defects in rotary nickel-titanium files after clinical use . J Endodon . 2000;26:161–165
  101. Haikel Y , Serfaty R , Bateman G , Senger B , Allemann C . Dynamic and cyclic fatigue of engine-driven rotary nickel-titanium endodontic instruments . J Endodon . 1999;25:434–440
  102. Ruddle CJ . nickel-titanium rotary instruments: current concepts for preparing the root canal system . Aust Endod J . 2003;29:87–98
  103. Blum JY , Machtou P , Micallef JP . Location of contact areas on rotary Profile instruments in relationship to the forces developed during mechanical preparation on extracted teeth . Int Endod J . 1999;32:108–114
  104. Schrader C, Peters OA. Analysis of torque and force during step-back with differently tapered rotary endodontic instruments in vitro. J Endodon (in press).
  105. Yared GM , Bou Dagher FE , Machtou P . Influence of rotational speed, torque and operator's proficiency on ProFile failures . Int Endod J . 2001;34:47–53
  106. Yared G , Bou Dagher F , Kulkarni K . Influence of torque control motors and the operator's proficiency on ProTaper failures . Oral Surg Oral Med Oral Pathol Oral Radiol Endod . 2003;96:229–233
  107. Gambarini G . Cyclic fatigue of ProFile rotary instruments after prolonged clinical use . Int Endod J . 2001;34:386–389
  108. Yared G , Kulkarni GK , Ghossayn F . Torsional properties of new and used rotary K3 NiTi files . Aust Endod J . 2003;29:75–78
  109. Mandel E , Adib-Yazdi M , Benhamou L-M , Lachkar T , Mesqouez C , Sobel M . Rotary Ni-Ti ProFile systems for preparing curved canals in resin blocks: influence of operator on instrument breakage . Int Endod J . 1999;32:436–443
  110. Sonntag D , Guntermann A , Kim SK , Stachniss V . Root canal shaping with manual stainless steel files and rotary Ni-Ti files performed by students . Int Endod J . 2003;36:246–255
  111. Mesgouez C , Rilliard F , Matossian L , Nassiri K , Mandel E . Influence of operator experience on canal preparation time when using the rotary Ni-Ti ProFile system in simulated curved canals . Int Endod J . 2003;36:161–165
  112. Sonntag D , Delschen S , Stachniss V . Root-canal shaping with manual and rotary Ni-Ti files performed by students . Int Endod J . 2003;36:715–723
  113. Barbakow F , Lutz F . The ‘Lightspeed’ preparation technique evaluated by Swiss clinicians after attending continuing education courses . Int Endod J . 1997;30:46–50
  114. Cailleteau JG , Mullaney TP . Prevalence of teaching apical patency and various instrumentation and obturation techniques in United States dental schools . J Endodon . 1997;23:394–396
  115. Goldberg F , Massone EJ . Patency file and apical transportation: an in vitro study . J Endodon . 2002;28:510–511
  116. Zelada G , Varela P , Martin B , Bahillo JG , Magan F , Ahn S . The effect of rotational speed and the curvature of root canals on the breakage of rotary endodontic instruments . J Endodon . 2002;28:540–542
  117. Poulsen WB , Dove SB , del Rio CE . Effect of nickel-titanium engine-driven instrument rotational speed on root canal morphology . J Endodon . 1995;21:609–612
  118. Karagoz-Kucukay I , Ersev H , Engin-Akkoca E , Kucukay S , Gursoy T . Effect of rotational speed on root canal preparation with Hero 642 rotary Ni-Ti instruments . J Endodon . 2003;29:447–449
  119. Wu MK , van der Sluis LWM , Wesselink PR . The capability of two hand instrumentation techniques to remove the inner layer of dentine in oval canals . Int Endod J . 2003;36:218–224
  120. Tepel J . Experimentelle Untersuchungen über die maschinelle Wurzelkanalaufbereitung . Berlin: Quintessenz Verlags-GmbH; 2000;
  121. Hülsmann M , Heckendorff M , Lennon A . Chelating agents in root canal treatment: mode of action and indications for their use . Int Endod J . 2003;36:810–830
  122. Bramante CM , Betti LV . Comparative analysis of curved root canal preparation using nickel-titanium instruments with or without EDTA . J Endodon . 2000;26:278–280
  123. McKendry DJ . Comparison of balanced forces, endosonic, and step-back filing instrumentation techniques: quantification of extruded apical debris . J Endodon . 1990;16:24–27
  124. Al-Omari MA , Dummer PM . Canal blockage and debris extrusion with eight preparation techniques . J Endodon . 1995;21:154–158
  125. Beeson TJ , Hartwell GR , Thornton JD , Gunsolley JC . Comparison of debris extruded apically in straight canals: conventional filing versus ProFile .04 Taper series 29 . J Endodon . 1998;24:18–22
  126. Reddy SA , Hicks ML . Apical extrusion of debris using two hand and two rotary instrumentation techniques . J Endodon . 1998;24:180–183
  127. Hinrichs RE , Walker WA , Schindler WG . A comparison of amounts of apically extruded debris using handpiece-driven nickel-titanium instrument systems . J Endodon . 1998;24:102–106
  128. Yusuf H . The significance of the presence of foreign material periapically as a cause of failure of root treatment . Oral Surg Oral Med Oral Pathol . 1982;54:566–574
  129. Sjögren U , Hagglund B , Sundqvist G , Wing K . Factors affecting the long-term results of endodontic treatment . J Endodon . 1990;16:498–504
  130. Siqueira JF . The etiology of root canal treatment failure: why well-treated teeth can fail . Int Endod J . 2001;34:1–10
  131. Izu KH , Thomas SJ , Zhang P , Izu AE , Michalek S . Effectiveness of sodium hypochlorite in preventing inoculation of periapical tissue with contaminated patency files . J Endodon . 2004;30:92–94
  132. Kerekes K , Tronstad L . Long-term results of endodontic treatment performed with a standardized technique . J Endodon . 1979;5:83–90
  133. Fan B , Wu M-K , Wesselink P . Leakage along warm gutta-percha fillings in the apical canals of curved roots . Endod Dent Traumatol . 2000;16:29–33
  134. Wu MK , Wesselink PR , Walton RE . Apical terminus location of root canal treatment procedures . Oral Surg Oral Med Oral Pathol Oral Radiol Endod . 2000;89:99–103
  135. Dummer PMH , McGinn JH , Rees DG . The position and topography of the apical canal constriction and apical foramen . Int Endod J . 1984;17:192–198
  136. Kast'akova A , Wu MK , Wesselink PR . An in vitro experiment on the effect of an attempt to create an apical matrix during root canal preparation on coronal leakage and material extrusion . Oral Surg Oral Med Oral Pathol Oral Radiol Endod . 2001;91:462–467
  137. Hör D , Attin T . The accuracy of electronic working length determination . Int Endod J . 2004;37:125–131
  138. Davis RD , Marshall JG , Baumgartner JC . Effect of early coronal flaring on working length change in curved canals using rotary nickel-titanium versus stainless steel instruments . J Endodon . 2002;28:438–442
  139. Kuttler Y . Microscopic investigation of root apexes . J Am Dent Assoc . 1955;50:544–552
  140. Kerekes K . Evaluation of standardized root canal instruments and obturating points . J Endodon . 1979;5:145–150
  141. Byström A , Sundqvist G . Bacteriologic evaluation of the efficacy of mechanical root canal instrumentation in endodontic therapy . Scand J Dent Res . 1981;89:321–328
  142. Dalton BC , Ørstavik D , Phillips C , Pettiette M , Trope M . Bacterial reduction with nickel-titanium rotary instrumentation . J Endodon . 1998;24:763–767
  143. Shuping GB , Ørstavik D , Sigurdsson A , Trope M . Reduction of intracanal bacteria using nickel-titanium rotary instrumentation and various medications . J Endodon . 2000;26:751–755
  144. Ram Z . Effectiveness of root canal irrigation . Oral Surg Oral Med Oral Pathol . 1977;44:306–312
  145. Usman N , Baumgartner JC , Marshall JG . Influence of instrument size on root canal debridement . J Endodon . 2004;30:110–112
  146. Coldero LG , McHugh S , MacKenzie D , Saunders WP . Reduction in intracanal bacteria during root canal preparation with and without apical enlargement . Int Endod J . 2002;35:437–446
  147. Rollison S , Barnett F , Stevens RH . Efficacy of bacterial removal from instrumented root canals in vitro related to instrumentation technique and size . Oral Surg Oral Med Oral Pathol Oral Radiol Endod . 2002;94:366–371
  148. Walsch H. The hybrid concept of NiTi rotary instrumentation. Dent Clin North Am (in press).
  149. McCann JT , Keller DL , LaBounty GL . Remaining dentin/cementum thickness after hand or ultrasonic instrumentation . J Endodon . 1990;16:109–113
  150. Lertchirakarn V , Palamara JE , Messer HH . Patterns of vertical root fracture: factors affecting stress distribution in the root canal . J Endodon . 2003;29:523–528
  151. Schilder H . Filling root canals in three dimensions . Dent Clin North Am . 1967;Nov:723–744
  152. Ruddle CJ . Three-dimensional obturation: the rationale and application of warm gutta percha with vertical condensation . J Massachusetts Dent Soc . 1994;43:15–18
  153. Buchanan LS . The standardized-taper root canal preparation: part 1. Concepts for variably tapered shaping instruments . Int Endod J . 2000;33:516–529
  154. Allison DA , Weber CR , Walton RE . The influence of the method of canal preparation on the quality of apical and coronal obturation . J Endodon . 1979;5:298–304
  155. Wu M-K , Fan B , Wesselink P . Leakage along apical root fillings in curved root canals. Part I: effects of apical transportation on seal of root fillings . J Endodon . 2000;26:210–216
  156. Kirkevang LL , Hørsted-Bindslev P . Technical aspects of treatment in relation to treatment outcome . Endod Topics . 2002;2:89–102

 The author thanks Drs. C. I. Peters and M. Zehnder for helpful criticisms and cand med dent E. Radzik for technical assistance.Address requests for reprints to Dr. Ove Peters, Clinic for Preventive Dentistry, Periodontology and Cariology, Center of Dental and Oral Medicine and Cranio-Maxillofacial Surgery, University of Zürich, Plattenstr. 11, CH-8028 Zurich, Switzerland. e-mail: ove.peters@zzmk.unizh.ch.

PII: S0099-2399(05)60236-1

doi: 10.1097/01.DON.0000129039.59003.9D

Journal of Endodontics
Volume 30, Issue 8 , Pages 559-567 , August 2004