Procedural errors in endodontics
- 2. Related to access opening of the pulp space Related to canal shaping and cleaning Related to obturation
- 3. RELATED TO ACCESS OPENING OF THE PULP A. Treating the wrong tooth Prevention – -Make a suitable mark on the radiograph and also on the tooth in question before application of rubber dam -Alternatively, the initial access cavity into the enamel or dentino-enamel junction can be completed before the rubber dam B. Incomplete removal of caries Secondary caries under restoration;-one must study the preoperative radiograph under magnification and good lighting, if any doubt exists, the entire filling should be removed and the cavity redesigned accordingly. old occlusoproximal cavities should be removed distal caries; clinician might concentrate on access opening in the mesial part of the tooth and cause incomplete removal of caries ****such teeth will get re-infected in the future and ultimately fail, coronal leakage
- 5. C .Access opening through full- coverage restoration If a soft carious lesion is suspected under the crown from a radiograph, one should remove the crown even at the cost of the remaining tooth structure Burs are available for cutting through ceramic crown without chipping the crown They are also available for cutting through the metal crowns for easy access
- 6. D. inability to locate extra canals/missed canals Causes failure to externalize internal anatomy lack of knowledge pertaining to root canal anatomy, confirguration and its variations improper access and not observing the basic cavity design features incomplete deroofing of the pulp chamber incomplete removal and shaping of the lateral walls of the pulp chamber Prevention and action Good periapical radiographs preoperatively and during cleaning and shaping observe radiographs under magnification multiple radiographs in varying angulations to better understand the morphology of the tooth Use DG16 or size 06/08/10 ISO k- file instruments to locate the orifices C+ file and profinder
- 8. E. iatrogenic perforations (cervical perforations) Management of nonfurcal cervical perforations hemorrhage control with 1:50,000 epinephrine followed by perforation repair with MTA Prevention; one must study the crown root angulations esp. of the max. lat. Incisors and the mad. first premolar when removing caries, one must be careful not remove healthy dentine which might undermine the tooth structure and result in a perforation Management of cervical perforations in the furcation area Once there’s blood flooding, one must suspect a perforation which can be confirmed with a radiograph or apex locator MTA is the material of choice for sealing perforations The patient should be informed that a patient has occurred and the prognosis discussed
- 9. Prevention of cervical perforations in the furcation area study the preoperatively radiograph and evaluate the pulp chamber morphology access bur penetration for depth and angulation should be confirmed before proceeding straight line access is cardinal “stay lingual rule” for max. lat. Incisor and mad. First premolar remove existing crowns and old restorations For calcified chambers and pulp spaces, the endodontists must externalize the internal tooth anatomy
- 11. ERRORS RELATED TO CLEANING AND SHAPINGa. Canal blockage and ledge formation. Prevention of canal blockage;- -Always use the smaller instrument first -Use instruments in sequential order -Pre-curve the stainless steel instruments -Use copious amount of irrigants -Recapitulate frequently -Dispose off instruments suitably
- 12. Causes Not extending the access cavity sufficiently to allow adequate access to the apical third Incorrect assessment of canal curvature Erroneous root canal length determination Forcing and driving the instruments into the canal Using non-curved stainless steel instrument Failing to use instruments in sequential order Overuse of reaming motion Inadequate irrigation Over relying on chelating agents Attempting to retrieve broken instruments Attempting to prepare calcified root canals Creating apical blockages Attempting instruments into proximal cavities or restorations Prevention Preoperative radiograph to assess unusual root canal curvature Patency should be maintain throughout cleaning and shaping Recapitulation Work passively without forcing the instruments into the canal Never force an instrument apically Work sequentially by increasing the sizes of the instruments without jumping to large numbers
- 14. deviation from normal canal anatomy Zipping; an apical transportation of a curved canal caused due to improper shaping technique Transportation Elbow; is the narrowest portion of a zipped canal Management prevention is the best form of management -adhering to principles of root canal instrumentation and appreciation of canal anatomy and instrument dynamics -in cases of a zip or transportation, any type of obturation can be used but thermoplasticized technique is the best
- 15. c. instrument separation in the canal Causes -Cyclic fatigue -Torsional fatigue -Carelessness in the instrumentation technique Treatment plan -instrument retrieval, coronal a third -by passing the instrument and making it part of the obturation, beyond a curvature, apical a third, narrow canals -surgical intervention in the form of hemi section of the root or root resection in roots with apical third instrument separation
- 17. d. obstruction from previous obtrutrating materials Gutta-percha Can be removed by application of; -Mechanical force in the form of instrumentation; canal orifice are reopened mechanically by forcing No, 20 or 25 H-file through the orifice or Gates Glidden drill -Heat to sear and soften the gutta percha ; with an excavator -Solvents; to assist sequence instrumentation, used be used carefully, not recommended for apical thirds -Ultrasonics -Combination of the above Silver Cone Not removed as easily as GP unless the butt end of the silver cone extends into the pulp chamber which is vibrated with an ultrasonic scaler to break the cementing media Cone is then seized with a pair of narrow- beaked pliers(stieglitz) If the cone extends slightly into the pulp chamber, it can often be made loose by vibrating with an ultrasonic scaler
- 19. PROCEDURAL ERRORS FROM OBTURATINGa. Under filling of GP Instability to seat the master cone to the estimated full working length- Occurs usually due to loss of working length as a result of packing dentinal mud into the pulp space Hints ;- Recapitulation and irrigation Obtain a radiograph after this procedure and reposition the master cone Over filling of GP Instrumentation beyond the constriction Should not occur if the basic biological and mechanical principles are observed as cardinal rules
- 20. ….OTHERS Aspiration or Ingestion of endodontic instruments Can be a clinical disaster ending up in the need for major surgery Preventable procedural error Use rubber dam High power suction
- 21. EVALUATION OF ENDODONTIC TREATMENT Clinical Evaluation Presence of symptoms though indicates the presence of pathology, but absence of a pain or any other symptoms does not confirm the absence of a disease. A little correlation exists between the presence of symptoms and the periapical disease. Clinical criteria for success • No tenderness to percussion or palpation • Normal tooth mobility • No evidence of subjective discomfort • Tooth having normal form, function and esthetics • No sign of infection or swelling • No sinus tract or integrated periodontal disease • Minimal to no scarring or discoloration
- 22. Radiographic Evaluation The radiographic criteria for failures are development of radiographic periapical areas of rarefaction after the endodontic treatment, in cases where they were not present before the treatment or persistence or increase in size of the radiolucency after the treatment. To predict the success or failure, one should be able to accurately compare the radiographs taken at different times. Radiographic criteria for success of endodontic treatment • 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.
- 23. Histological Evaluation Histological criteria for success or failure of endodontic therapy may include absence of inflammation and regeneration of periodontal ligament, bone and cementum following endodontic therapy. Histological criteria for success • Absence of inflammation • Regeneration of periodontal ligament fbers • Presence of osseous repair • Repair of cementum • Absence of resorption • Repair of previously resorbed areas
- 24. DEFINITIONS RELATED TO ENDODONTIC TREATMENT OUTCOME Healed: Both clinical and radiographic presentations are normal Healing: It is 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.
- 25. SUCCESS/FAILURE OF ENDODONTIC TREATMENTThe percentage of successfully treated cases naturally varies with judgment in selection of cases for treatment, with the method of therapy, with the skill of the operator, with the technical difficulties, and with other factors. Nevertheless, some idea of the probability of success can be gained from published reports
- 26. CAUSES OF ENDODONTIC FAILURELocal factors • Infection • Incomplete debridement of the root canal system • Excessive hemorrhage • Over instrumentation • Chemical irritants • Iatrogenic errors – Separated instruments –Canal blockage and ledge formation – Perforations – Incompletely filled teeth – Overfilling of root canals • Corrosion of root canal fillings • Anatomic factors • Root fractures • Traumatic occlusion • Periodontal considerations Systemic factors • Nutritional deficiencies • Diabetes mellitus • Renal failure • Blood dyscrasias • Hormonal imbalance • Autoimmune disorders • Opportunistic infections • Aging • Patients on long term steroid therapy
Editor's Notes
- #16: Kits available for removing separated instruments, Endo extractor Mounce extractor Masselann kit