Urgent managemnt of procedural incidents Flashcards
What procedural errors can occur in endodontics?
File separation, perforation, extrusion of sodium hypochlorite, other errors (e.g., voids in obturation, extrusion of obturation material, transportation of canal).
What are the 2 modes files can fracture?
Cyclic fatigue and torsional fatigue.
What is cyclic fatigue?
When an instrument is rotated in a curved canal due to repeated compressive and tensile stresses.
What is torsional fatigue?
Occurs when the tip of the file binds in the canal and the motor continues to rotate.
Which instruments do not show plastic deformation (Warning sign for file fracture)?
NiTi files.
Which type of file is more likely to fracture?
NiTi.
Where do files most commonly fracture?
Apical third.
What can be done to minimise risk of file fracture?
Ensure straight line access, avoid overuse of files, ensure speed and torque settings are correct, inspect files for unwinding during use, continually move files within canal in no more than 3 strokes, continual irrigation and flushing of debris, advance files gradually by maximum of 2mm at a time.
What can be done to manage file fracture in coronal third of a vital tooth?
Remove file aiming for minimum dentine removal.
What can be done to manage file fracture in the mid third of a vital tooth?
Attempt to bypass the file, if not try to obturate fragment, monitor, if failure, consider surgical options.
How to manage file fracture in apical third of a vital tooth?
Obturate canal up to fragment.
How to manage file fracture in non-vital teeth?
Bypass if possible, do not need to remove. If bypass unsuccessful, inter-appt medicament (CaOH)2 for 2-4 weeks combined with NaOCl agitation follow up.
What are the two main types of perforation?
Iatrogenic accident and pathologic.
Give 3 reasons for pathologic perforation.
Resorptive, carious, fracture.
Where can perforations in coronal third occur?
Lateral and furcal.
When do perforations in coronal third often occur?
When trying to locate canal orifices.
What are the 2 types of perforation in the mid third?
Strip and lateral.
When do strip perforations occur?
Cured canal is instrumented too heavily on the inside surface.
Where can perforations in the apical third occur?
Apical and lateral.
How prevalent are iatrogenic perforations?
3-10% of all endodontically treated teeth.
In which arch are perforations more likely?
Maxilla.
What signs might indicate a perforation?
Bleeding, pain (if no LA given), consistent apex locator readings of 0 above apex.
What late signs may indicate a perforation?
Radiography, ST pathology (inflammation/sinus), CBCT.
What factors affect the prognosis of perforation?
Site (supracrestal or apical), size, time to repair.
How can the risk of perforation be reduced?
Use magnification and good lighting, remove impediments to straight line access, use pre-op imaging and take intra-op images as needed, ensure glide path with size 20 hand file before using rotary, copious, gentle irrigation, balancing force technique for hand files, follow manufacturer protocols, never force a file, do not use rotary if suspect a blockage/ledge, in multirooted teeth, always brush the file away from the furcation.
How to manage perforations?
Magnification, assessment of prognosis, repair with hydraulic calcium silicate cement if possible, if not possible, consider surgical approach, monitor, consider referral.
What is recapitulation?
Between each new rotary file, use a smaller hand file. This prevents blockages.
What damage can be caused by NaOCl extrusion?
Pain, oedema, ulceration, bruising, cellulitis, trismus, allergic response, damage to adjacent structures.
With which teeth is trismus most likely to occur?
Lower molars.
Which sex is more commonly affected by NaOCl extrusion?
Female.
What intra-operative factors can affect the severity of NaOCl extrusion?
Size of apical opening, force applied when irrigating, concentration of NaOCl, volume extruded, position of irrigant tip, irrigant tip gauge and shape.
What can be done to reduce the risk of NaOCl extrusion?
Use of rubber dam, measure files to correct working length, use of stoppers for irrigation syringes, use of safe ended needles, use of index finger instead of thumb for irrigation, ensure syringe is not locked in canal by using an in and out motion during irrigation, passive movement of syringe, ask patient to signal if they get a bad taste, use of a lower concentration of NaOCl.
Which type of syringes should be used for irrigation?
Side venting.
What distance from apical constriction can you effectively irrigate?
4mm.
How to immediately manage a NaOCl accident?
Block LA to manage pain, insert paper point to remove excess NaOCl, irrigate canal with saline (water if saline not available), let canal drain, aided with further paper points, dress tooth with calcium hydroxide and temporary filling, pain management - more LA / OTC analgesics, swelling management - NSAIDs.
What ongoing management should occur for NaOCl extrusion?
Telephone follow up on same day/evening, daily phone calls for next few days, RV in 1 week, if necrosis, prescribe antibiotics - amoxicillin or metronidazole, can consider other medications (e.g., steroids/antihistamines), refer to maxfax if concerned with sequelae, call patient 1-2 times a week until satisfied it is resolved, only obturate once symptoms have resolved.
What is the duty of candour?
Ethical responsibility of all healthcare workers to be open and honest, even when something goes wrong.
