Endodontic Mishaps: Management, Prevention & Prognosis

Posted on Aug 24, 2024 in Biology

Endodontic Mishaps: Management, Prevention, and Prognosis

Introduction

Endodontic mishaps are unfortunate occurrences that can happen during root canal treatment. Some are due to inattention, while others are unpredictable. This comprehensive guide outlines various mishaps, their management, prognosis, and prevention strategies.

Management Steps

  1. Detection: Identifying the mishap accurately.
  2. Correction: Implementing appropriate corrective measures.
  3. Prognosis: Assessing the long-term outcome and success rate.
  4. Prevention: Strategies to minimize the risk of future occurrences.

I. Access-Related Mishaps

1. Treating the Wrong Tooth

  • Etiology: Misdiagnosis or incorrect isolation.
  • Detection: Persistent symptoms or radiographic discrepancies.
  • Correction: Treat both the intended and the incorrectly accessed tooth.
  • Prevention: Accurate diagnosis and marking the correct tooth.

2. Missed Canals

  • Etiology: Lack of knowledge or inadequate access preparation.
  • Detection: Off-centered radiographic appearance.
  • Correction: Locate and treat the missed canal.
  • Prevention: Proper access preparation, thorough knowledge of root canal anatomy, magnification (loupes or microscope), and regular radiographs.
  • Prognosis: Decreased success rate, depending on the type of canal missed.

3. Compromised Integrity of Existing Restoration

  • Etiology: Porcelain crown chipping during access preparation or rubber dam application.
  • Correction: Repair or reconstruct the damaged restoration.
  • Prevention: Consider crown removal or inform the patient of the potential risk.

4. Supracrestal or Furcation Perforations

  • Definition: Undesirable communication between the pulp space and the external tooth surface above the periodontal attachment.
  • Etiology: Inadequate knowledge of pulpal floor depth.
  • Detection: Bleeding (direct or indirect) and radiographic confirmation with a file.
  • Correction: Immediate repair with materials like MTA, Cavit, amalgam, calcium hydroxide, Super EBA, glass ionomer cement, or hemostatic agents.
  • Prevention: Proper access preparation, knowledge of root canal anatomy, and radiographic guidance.
  • Prognosis: Decreased success rate depending on the location, duration of exposure, sealing ability, and accessibility to the main canal.

5. Crown/Root Fracture

  • Etiology: Pre-existing crack exacerbated by access preparation and chewing forces.
  • Detection: Mobility.
  • Correction: Remove and evaluate; if a chisel fracture, remove the mobile part; support with a copper band during treatment; consider extraction.
  • Prognosis: Unpredictable, generally less favorable than an intact tooth.
  • Prevention: Reduce occlusion and avoid over-extended access preparation.

II. Instrumentation-Related Mishaps

1. Over-instrumentation (External Transportation)

  • Etiology: Overzealous preparation, excessive flaring, ledges, and apical transportation.
  • Prevention: Adhering to biomechanical principles.

2. Ledge Formation (Internal Transportation)

  • Etiology: Indirect access, inadequate knowledge, and the use of large or rigid instruments.
  • Detection: Shortened working length and tactile sensation.
  • Correction: Copious irrigation and lubrication (avoiding EDTA), using small, sharp, pre-curved files.
  • Prevention: Proper access, knowledge of root canal anatomy, radiographic guidance, pre-curving files, using NiTi files with non-cutting ends, and avoiding large instruments.
  • Prognosis: Decreased success rate depending on the size of the preparation and pulp vitality.

3. Radicular Perforations

  • Etiology: Using instruments that are too large or too long, overflaring, and cervical/furcal/supracrestal perforations.
  • Detection: Direct vision (with a microscope), pain, bleeding, and radiographic confirmation.
  • Correction: Small perforations can be sealed internally; larger perforations may require internal and surgical repair using MTA or Geristore.
  • Prevention: Proper access, knowledge of root canal anatomy, radiographic guidance, anti-curvature filing, careful use of rotary instruments, and avoiding large instruments.
  • Prognosis: Decreased success rate depending on various factors.

4. Canal Blockage

  • Etiology: Debris compaction.
  • Detection: Shortened working length, tactile sensation, and radiographic confirmation.
  • Correction: Recapitulation with a chelating agent and pre-curved files.
  • Prevention: Adequate irrigation and lubrication, and regular recapitulation.
  • Prognosis: Varies depending on the stage, pulp status, and canal size.

5. Instrument Separation and Foreign Bodies

  • Etiology: Locked or stressed instruments, excessive bending.
  • Detection: Shortened working length, tactile sensation, and radiographic confirmation.
  • Correction: Depending on the location, surgical or non-surgical removal (using ultrasonics), bypass, or filling.
  • Prevention: Avoiding stressed instruments, preventing wedging, sequential preparation, and using lubricants.
  • Prognosis: Varies depending on the location, pulp status, and size of the separated instrument.

III. Obturation-Related Mishaps

1. Over- or Under-extension of Root Canal Fillings

  • Prevention: Accurate working length determination, radiographic confirmation, and using apical barriers if necessary.
  • Prognosis: Overextension can affect apical seal quality; under-extension can lead to reinfection.

2. Nerve Paresthesia

  • Etiology: Extrusion of formaldehyde-containing sealers, over-instrumentation, over-extension, or surgery.
  • Detection: Sensory alterations (temporary or permanent).
  • Correction: Corticosteroids or surgical decompression.
  • Prevention: Careful technique and material selection.

3. Vertical Root Fracture

  • Etiology: Excessive force during obturation or post placement.
  • Detection: Sudden crunching sound, pain, halo (tear-drop) radiolucency, deep periodontal defect, or exploratory surgery.
  • Correction: Extraction.
  • Prevention: Controlled force during obturation and post placement.
  • Prognosis: Poor.

4. Post Space Perforation

  • Etiology: Use of end-cutting drills.
  • Detection: Bleeding and radiographic confirmation.
  • Correction: Sealing as with other perforations.
  • Prognosis: Depends on the location.
  • Prevention: Knowledge of anatomy, radiographic guidance, preparing the post space during obturation, and using solvents.

IV. Miscellaneous Mishaps

1. Hypochlorite Accident

  • Etiology: Forceful extrusion of NaOCl irrigant.
  • Detection: Pain, swelling, interstitial hemorrhage, and ecchymosis.
  • Correction: Reassurance, antibiotics, analgesics, antihistamines, cold compresses initially followed by heat, incision and drainage, and possible hospitalization with surgical intervention.
  • Prognosis: Generally favorable, but potential for paresthesia, scarring, and muscle weakness.
  • Prevention: Passive, slow irrigation with specialized needles.

2. Tissue Emphysema

  • Etiology: Air drying of the canal, surgical procedures, or hydrogen peroxide irrigation.
  • Detection: Dysphagia, dyspnea, rapid swelling, interstitial emphysema, erythema, crepitus, and respiratory difficulty.
  • Correction: Reassurance, palliative care, antibiotics, and airway management.
  • Prevention: Using paper points, horizontal positioning of the air syringe, and careful surgical technique.

3. Instrument Aspiration or Ingestion

  • Etiology: Not using a rubber dam.
  • Detection: May be asymptomatic or present with respiratory distress.
  • Correction: Remove accessible instruments with high suction, hemostats, or pliers; medical intervention may be necessary.
  • Prevention: **Always use a rubber dam!**

V. Antibiotics in Endodontics

Antibiotics are sometimes necessary in endodontic treatment, especially for systemic infections or immunocompromised patients. Common choices include penicillins, cephalosporins, metronidazole, and clindamycin. Proper selection and dosage are crucial to avoid antibiotic resistance and adverse effects.

VI. Isolation Techniques in Endodontics

Effective isolation is paramount in endodontic treatment. The rubber dam is the gold standard for direct isolation, providing a clean and dry operating field, protecting the patient and operator, and improving the properties of dental materials. Alternative isolation methods include cotton rolls, gauze, and high-volume evacuation.

Conclusion

Endodontic mishaps can be minimized with proper knowledge, meticulous technique, and adherence to established guidelines. This guide provides a comprehensive overview of common mishaps, their management, and prevention strategies to enhance the success and predictability of endodontic treatment.