Endodontic mishaps include procedural errors that can occur during root canal treatment such as ledge formation, canal perforation, separated instruments, and overfilling/underfilling of canals. It is important for practitioners to understand how to recognize, prevent, and treat these mishaps. Common causes include inadequate access, excessive force, or improper instrument use. Perforations require immediate sealing with materials like MTA to achieve the best prognosis. Separated instruments may be bypassed or retrieved, while ledges can sometimes be circumvented with smaller files. Overall, minimizing errors requires adherence to principles like conservative access, copious irrigation, and careful instrumentation.

1. ENDODONTIC MISHAPS

2. Endodontic mishaps :
Constitute the procedure related errors or accidents seen
during the endodontic procedures.

3. •
Knowledge of etiologic factors involved
•
Methods of recognition
•
Methods of treatment/correction
•
Effects of the mishap on the prognosis of the root
canal therapy

4. Some of the examples of procedural accidents are:
•
Accidental swallowing /aspiration of an endodontic
instrument
•
Perforations
•
Ledge formations
•
Missed canals
•
Overfilled/underfilled canals
•
Vertically fractured roots
•
Separated instruments

5. Legal implications
Does the patient need to know about the mishap ?????????
The patient should be informed about
•
the incident
•
the procedures necessary for its correction
•
alternative treatment modalities
•
effect of the mishap on the prognosis

6. ENDODONTIC MISHAPS
ACCESS
PREPARATION
CLEANING
AND
SHAPING
OBTURATION
POST
ENDODONTIC
RESTORATIONS

7. ACCESS RELATED :
Main objective of access cavity
▬►
•
straight line access to the canal orifices
•
unobstructed access to the apical foramen

8. Accidents most commonly encountered during access
opening are:
•
Treating the wrong tooth
•
Missed canals
•
Damage to existing restoration
•
Access cavity perforations
•
Crown fractures

9. Perforations:
Results from failure to direct the bur with the long access
of the crown
Commonly encountered with the mandibular anteriors due
to their inclination

10. Perforation of the furcation is most commonly encountered
in posterior teeth with calcified pulp chambers

11. Tooth with crown require special care

12.  Dentist should not rely completely on the orientation of
the bur as seen on the mirror image
 Periodically the preparation should be stopped and the
access should be examined
 Especially when dealing with calcified chambers

13. Prevention:
Clinical examination
 Thorough knowledge of tooth morphology and
internal anatomy
 Location and angulation of the tooth with respect
to the adjacent teeth as well as the alveolar bone
Radiographic examination
 Radiographs should be taken at different
angulations
 Presence of calcifications, resorptive defects

14. Operative procedures:
Rubber dam has to be always placed during endodontic
therapy
Access cavity preparation without rubber dam is indicated in
cases like



Teeth inclines lingually or bucally
teeth with crowns/large restorations
Calcified chambers

15. This will help in judging the crown root alignment with
respect to the adjacent tooth or the alveolar bone
But once access is achieved the rubber dam should be
placed.
No file/broach should be placed inside the patients mouth
without the rubber dam

16. Quadrant isolation may help in recognizing the orientation
of the tooth to the adjacent tooth
Specialized endodontic burs like the Endo-Z burs with non
cutting tips will prevent the perforations especially in the
furcations

17. In case of calcified chambers or teeth with a crown, a bur
can be placed inside the access and then a radiograph is
taken for orientation of the the bur with the canal

18. Important aids for locating canals
-Magnification
- illumination
Identification of perforations:
 Continuous haemorrhage
 Sudden pain during working length determination
 Bad taste during irrigation with hypochloride
 Premature reading with the EAL
 Radiographically malpositioned fie

19. Treatment :
Lateral root perforations:
If above the crestal bone → good prognosis
 Intracoronal placement of restorative material like
Glass ionomer, composite, MTA
 Surgical exposure and sealing the defect externally
Below the crestal bone [coronal third of the root] →
Attachment loss →periodontal pocket
•
Crown lengthening/orthodontic extrusion to expose
the defect and repair

20. Furcation perforations:
Direct : floor of the pulp chamber

21. Strip perforations:
Normally caused by the excessive flaring of the canals
with rotary instruments
Mostly inaccessable
Treated by sealing with MTA

22. Prognosis depends on
size of the perforation
site of perforation
time taken to seal it
Best prognosis if the perforation is sealed immediately.
The sealing material should not block the access of the
canals

23. CLEANING AND SHAPING
Most common procedural errors during cleaning and shaping
are
•
Ledge formation
•
Artificial canal creation
•
Root perforation
•
Instrument separation
•
Extrusion of the irrigating solution periapically

24. Ledge formation:
Ledge is created when the working length
can no longer be negotiated and the
original patency of the canal is lost
Main causes:
•
Inadequate straight line access into the
canal
•
Inadequate irrigation or lubrication
•
Excessive enlargement of a curved
canal with files
•
Packing debris in the apical portion of the canal

25. Small, curved and long canals are most prone to ledging
Prevention :
•
Preoperative radiographic evaluation of the root curvatures
•
Straight line access to the canals
•
Precurving the files before the insertion
•
Accurate working length
•
Frequent recapitulation and use of lubricants
•
Recapitulate with a file smaller than the MAF
•
Each file must be worked until loose before moving to the
next size

26. Treatment :
Try to bypass the ledge with the help of smaller instruments
like #8 or #10
Prognosis :
Depends on the amount of debris present beyond the ledge

28. Creating an artificial canal:
Deviation from the original canal pathway.
Same factors that cause a ledge
Once a ledge is formed and is not diagnosed, the operator
tries to regain the
working length and uses force to
instrument in the direction of the ledge creating a new
pathway

29. Root perforations
Apical perforations
Lateral perforations
Coronal root perforations

30. Separated instruments:
Instruments fractured in the canals.
Recognition:
Sudden decrease in the length of the file after removal
from the root canal
Subsequent loss of patency and working length

31. Prevention:
Check the instruments visually for any deformative each
time the instrument is taken out of the canal
Files are used sequentially without jumping from a small
size to larger size
Treatment:
Bypass the instrument
Retrieve the instrument
Leave the instrument inside the canal

33. Aspiration or ingestion
Use of rubber dam is mandatory before placing any file in the
canal orifice
The rubber dam clamp is secured with a floss always.
If rubber dam is not used ,atleast tie the instruments with a
floss such that a part of the floss hangs out of the patients
mouth

34. The patient with the aspirated instrument is referred
to an emergency for the surgical removal of
instrument
the

35. Extrusion of the irrigant:
Cause:
•
Wedging the needle tightly in the canal during irrigation
•
Forceful expression of the irrigant
Indicators
•
Sudden prolonged and sharp pain during irrigation with
NaOCl
•
Followed by rapid diffuse swelling indicating the
penetration of the fluid into the tissue spaces

36. How to recognize a NaOCl accident
•
Immediate severe pain (for 2-6 minutes)
•
Ballooning or immediate edema in adjacent soft tissue
•
because of perfusion to the loose connective tissue
•
Extension of edema to a large site of the face such as
cheeks, peri- orbital region, or lips
•
Ecchymosis on skin or mucosa as a result of profuse
interstitial bleeding
•
•
Profuse intraoral bleeding directly from root canal
Chlorine taste or smell because of injected NaOCl to
maxillary sinus

37. •
Severe initial pain replaced with a constant discomfort or
numbness, related to tissue destruction and distension
•
Reversible or persistent anesthesia
•
Possibility of secondary infection or spreading of former
infection

38. How to treat a NaOCl accident
•
Remain calm and inform the patient about the cause
and nature of the complication.
•
Immediately irrigate with normal saline to decrease
the soft-tissue irritation by diluting
•
the NaOCl.
•
Let the bleeding response continue as it helps to
flush the irritant out of the tissues.
•
Recommend ice bag compresses for 24 hours (15minute intervals)to minimize swelling.

39. •
Recommend warm, moist compresses after 24 hours
(15-minute intervals).
•
Recommend rinsing with normal saline for 1 week to
improve circulation to the affected area.
•
•
For pain control
Initial control of acute pain could be achieved with
local anaesthesia
•
Antibiotics are not required
•
Analgesics are given

40. OBTURATION
UNDERFILLING
OVERFILLING

41. VERTICAL ROOT FRACTURE:
Causes:
 Over instrumentation of canals with increased force
 Cementation of an oversized post
Prevention :
 Less force during cleaning and shaping
 Finger spreaders induce less streses than the hand
spreaders

42. Clinically presents with a periodontal defect or a sinus
along the fracture line
Lateral radiolucency present along the border of fracture
of the root
Prognosis is poor

43. ACCIDENTS DURING POST PREPARATION:
Most commonly cause perforations
•
Caused due to improper selection of the size of the
drills to create the post space
•
Excessive force during the preparation.
•
Improper characteristics of the post like
short post
large post
•
Improper case selection

44. Clinically may present with
vertical root fracture
Perforation of the root
A fistulous tract extending to the base of the post
indicating a vertical fracture or a perforation site
Radiographs show a lateral radiolucency

45. Prognosis
Vertical root fractures ---------poor
Perforations----------good [surgically exposed and
sealed with MTA]