Diese Präsentation wurde erfolgreich gemeldet.
Wir verwenden Ihre LinkedIn Profilangaben und Informationen zu Ihren Aktivitäten, um Anzeigen zu personalisieren und Ihnen relevantere Inhalte anzuzeigen. Sie können Ihre Anzeigeneinstellungen jederzeit ändern.

Endodontic failures

Endodontic failures

  • Loggen Sie sich ein, um Kommentare anzuzeigen.

Endodontic failures

  1. 1. endodontic failures and retreatment
  2. 2. Introdution• In different studies success rate ranges from 54 percent to 95 percent.• The definition of success is ambiguous - stringent : radiographic and clinical normalcy - lenient : only clinical normalcy
  3. 3. Endodontic treatment outcome• Healed: both clinical and radiographic presentations are normal• Healing: it’s a dynamic process, reduced radiolucency combined with normal clinical presentation• Disease: No change or increase in radiolucency, clinical signs may or may not be present or vice versa
  4. 4. Evaluation of success• Success or failures following endodontic therapy could be evaluated from combination of clinical, histopathological and radio graphical criteria.
  5. 5. Clinical evaluation for success• No tenderness to percussion or palpation• Normal tooth mobility• No evidence of subjective discomfort• Tooth having normal form, function and aesthetics• No sign of infection or swelling• No sinus tract or integrated periodontal disease• Minimal to no scarring or discoloration
  6. 6. Radiographic evaluation for success• Normal or slightly thickened periodontal ligament space• Reduction or elimination of previous rarefaction• No evidence of resorption• Normal lamina dura• A dense three dimensional obturation of canal space
  7. 7. Histological evaluation for success• Absence of inflammation• Regeneration of periodontal ligament fibers• Presence of osseous repair• Repair of cementum• Absence of resorption• Repair of previously resorbed areas
  8. 8. Causes of the endodontic failures Bacteria somewhere in the root canal system Divided into local and systemic
  9. 9. Factors affecting success orfailure of endodontic therapy in every case• Diagnosis and the treatment planning• Radiographic interpretation• Anatomy of the tooth and root canal system• Debridement of the root canal space
  10. 10. Factors affecting success orfailure of endodontic therapy in every case• Quality and extent of apical seal• Quality of post endodontic restoration• Systemic health of the patient• Skill of the operator
  11. 11. Factors affecting success or failure of a particular case Factors affecting success or failure of a particular case• Pupal and Periodontal status• Size of periapical radioleucency• Canal anatomy• Crown and root fracture
  12. 12. Factors affecting success or failure of a particular case Factors affecting success or failure of a particular case• Iatrogenic errors• Extent and quality of the obturation• Quality of the post endodontic restoration• Time of post treatment evaluation
  13. 13. Local Factors causing endodontic failures• Infection• Incomplete debridement of the root canal system• Excessive hemorrhage• Chemical irritants• Iatrogenic errors
  14. 14. Infection• infected and necrotic pulp tissue→main irritant to the periapical tissues• The host parasite relationship 、 virulence of microorganisms , ability of infected tissues to heal→influence the repair of the periapical tissues• Endo success →debridement
  15. 15. Incomplete debridement of the root canal system• Main objective of root canal therapy→complete elimination of the microorganisms and their byproducts• Poor debridement → residual microorganisms 、 byproducts and tissue debris → recolonize
  16. 16. Excessive hemorrhage• Extirpation of pulp and instrumentation beyond periapical tissues• Local accumulation of the blood→mild inflammation• Extravasated blood cells and fluid : foreign body nidus for bacterial growth
  17. 17. Over instrumentation• Instrumentation beyond apical foramen→PDL and alveolar bone trauma→the prognosis of endodontic treatment ↓
  18. 18. Chemical irritants• Intracanal medicaments and irrigating solution →extruded in the periapical tissues→the prognosis of endodontic treatment ↓• One should take care while Using medicaments to avoid their periapical extrusion
  19. 19. Iatrogenic errors• Separated instruments—• Caused by improper or overuse of• instruments and forcing them in curved canals• Prognosis : no much affected in vital pulps poor in necrotic tissue.
  20. 20. Iatrogenic errors• Canal blockage and ledge formation—• Accumulation of dentin chips or tissue debris prevent the instruments to reach its full working length• Ledge formation—straight instruments in curved canals• These lead to bacteria & debris remained endo failure
  21. 21. Iatrogenic errors• Perforations—• Lack of knowledge of anatomy of the tooth, attention, misdirection of the instruments• Prognosis : location, time, perforation seal and size• Poor prognosis  remaining infected tissue
  22. 22. Iatrogenic errors• Incompletely filled teeth—• Teeth filled more than 2mm short of apex• Several studies shown :• poor prognosis—underfillings with necrotic pulps• Overfilling of root canals—• Overfilling extending ≧ 2mm beyond• radiographic apex• Continuous irritation of the periapical• tissues endo failure
  23. 23. Iatrogenic errors• Anatomic factors—• Such as : overly curved canals, calcifications,• numerous lateral and accessory canals,• bifurcations, C or S shaped canals• Problems in cleaning and shaping &• incomplete filling of root canals•  endodontic failure
  24. 24. Iatrogenic errors• Root fractures—• Partial or complete fractures of roots• Prognosis of teeth :• vertical root is poor than horizontal fractures• Traumatic occlusion –• Cause endo failures because of its effect on• periodontium
  25. 25. Systemic factors causing endodontic failures• Nutritional • Autoimmune disorders deficiencies • Opportunistic• Diabetes mellitus infections• Renal failure • Aging• Blood dyscrasias • Long term steroid• Hormonal imbalance therapy
  26. 26. Endodontic retreatment Before going/performing Case selection Prognosis ,Contraindications and problems Steps
  27. 27. Before going to endodontic retreatment• when should Treatment be considered• Patient’s needs• Strategic importance of the tooth• Periodontal evaluation of the tooth• Chair time & cost
  28. 28. Before performing to endodontic retreatment• May to prevent the potential disease• Remove/remade extensive coronal restoration• Technical problems• May not achieve better results• Filling materials have to be removed• Prognosis could be poorer• Patient might be more apprehensive
  29. 29. Case selection• Careful history• Anatomy of root canal , canal curvature, calcifications,unusual configurations• Quality of obturation• Iatrogenic complications• Cooperation of the patient
  30. 30. Factors affecting prognosis of endodontic treatment• Periapical radiolucency• Quality of the obturation• Apical extension of the obturation material• Bacterial status• Observation period• Postendodontic coronal restoration• Iatrogenic complication
  31. 31. Contraindications of endodontic retreatment• Unfavorable root anatomy• Untreatable root resorptions or perforations• Root or bifurcation caries• Insufficient crown/root ratio
  32. 32. Problems of endodontic retreatment• Unpredictable result• Frustration• Cost factor• Time consuming
  33. 33. Steps of Retreatment1. Coronal disassembly2. Establish access to root canal system3. Remove canal obstructions4. Establish patency5. Thorough cleaning, shaping and obturation of the canal
  34. 34. 1. Coronal Disassembly• Removal of existing • Access made through coronal restoration coronal restoration
  35. 35. Disadvantages ofAdvantages of gaining retaining aaccess through restoration:original restoration: a. Reduce visibility anda. Facilitate rubber dam accessibility placement b. Increased risks ofb. Maintaining form, irreparable errors function and aesthetics c. Increased risks ofc. Reducing the microbial infection if cost of replacement crown margins are poorly adapted
  36. 36. Advice:Remove the existing restorationEspecially: poor marginal adaptation, secondary cariesPlace temporary crown to maintain form, function and aesthetics.
  37. 37. 2. Establish Access to Root Canal SystemTeeth restored with post andcore:1.Post and core need to beremoved for gaining access toroot canal system2.Post and core can be perforatedto gain access
  38. 38. Posts can be removed by:1. Weakening retention of posts by use of ultrasonic vibration.2. Forceful pulling of posts but it increases the risk of root fracture3. Removing posts with the help of special pliers using post removal systems
  39. 39. Post Removal System(PRS)
  40. 40. Post Removal System(PRS)• 5 various designed trephines• Corresponding taps(microtubular tap)• Torque bar• Transmetal bur• Rubber bumpers• Extracting plier
  41. 41. 1-Transmental burEffeciently dooming of the post head
  42. 42. 2-Add lubricant• EX: RC Prep• Be placed on the post head to further facilitate the machining process
  43. 43. 3-Trephine burUse the largest bur to machine down the coronal 2-3 mm of the post.
  44. 44. 4-Rubber bumperinserted on the tab & pushed on the occlusalsurface.Act as a cushion, distribute the loads andprotect thetooth during the removal procedure.
  45. 45. 5-Microtubular tap• Inserted against the post head.• Screwed it into post with counter clockwise direction and strongly engage the post.
  46. 46. Post removal plier• Mount the post removal plier on tubular tap• Ultrasonic instrument using/torque bar inserting Ultrasonic instrument Screw knob Tubular tap Rubber bumper plier
  47. 47. Post removal plier1 -Nonsurgical Removal of Posts Broken Instruments - YouTube_x264.mp4
  48. 48. Removing Canal Obstructions andEstablishing Patency
  49. 49. Silver Point Removal A- Microsurgical forceps
  50. 50. Silver point removal B-Ultrasonic
  51. 51. Siver point removalC- Using Hedstroem files(H-files)
  52. 52. Silver Point RemovalE- Post removal system kit.D- Instrument removal system(IRS).
  53. 53. Gutta-Percha Removal• The relative difficulty in removing gutta-percha is influenced by some factors of canal system:  Length  Diameter  Curvature  Internal configuration• Progressive Manner : gutta-percha is best removed from canal in progressive manner to prevent its extrusion periapically
  54. 54. Gutta-Percha Removal• Coronal portion of gutta-percha should always be explored by Gates-Gliddens to:  Quickly : Remove gutta-percha quickly  Solvent : Provide space for solvents  Convenience : Improve convenience form• Gutta-percha can be removed by using:  Solvents  Hand instruments  Rotary instruments  Microdebrider
  55. 55. 1. Solvents• GP is soluble in:  Chloroform : most effective but carcinogenic with high concentratin , excessive filling in pulp chamber is avoided  Methyl chloroform  Benzene  Xylene  Eucalyptol oil  Halothane• GP dissolution should be supplemented by using hand instruments
  56. 56. 2. Hand Instruments Used mainly in apical portion of the canal.• Hedstroem files• Hot endodontic instrument like Reamer or files Poorly condenced GP can be pulled easily
  57. 57. 3. Rotary Instruments•They are Safe to be used in straight canals Recently:•ProTaper universal systems  Consisting of file :D1 D2 D3  500-700 rpm
  58. 58. Protaper universal system• D1 : Remove filling from the coronal third• D2 : Remove filling from the middle third• D3 : Remove filling from appical third
  59. 59. Microdebriders A small files with 90 degrees bends Removing remaining gutta-percha on the sides of canal walls
  60. 60. Pastes and Cement Soft setting pastes  Penetrated by endodontic instruments Hard setting cements  Softened by solvents: xylene, eucalyptol...... Then removed by files .  Ultrasonic devices
  61. 61. Separated Instruments and Foreign Objects Coronal third – attempt retrieval Middle third – attempt retrieval or bypass Apical third – surgical treat
  62. 62. Separated Instruments and Foreign Objects Attempt retrieval  Mechanism → Stieglitz pliers, Massermann extractor  Vibration → Ultrasonics  Accessibility → Modified Gates Glidden bur Bypass  Reamers or files with copious irrigation Surgical treat  Apicoectomy
  63. 63. Ultrasonic4-endo(instrument removal) - YouTube_x264.mp4
  64. 64. Instrument removal system (IRS) Can be used to remove the broken files microtube screw wedge
  65. 65. The beveled end of the microtube The introduction of the screw wedge which isoriented toward the outer wall of the rotated CCW to engage and displace the headcanal to “scoop up” the head of the of the file out the side window.broken file.
  66. 66. Completion of the Retreatment Thorough cleaning, shaping and obturation The outcome of retreatment  Short-term: no pain and swelling  Long-term: depended regaining canal patency & obturation of the root canal system Retreatment is mostly associated with procedural complication. Effective communication is required b/t dentist & patient.

×