lecture 7: iatrogenic misadventure and their sequelae

Question 1

the best prevention in endo is

Answer 1

intelligent case selection is key to success and prevention of predictable errors/incidents

Question 2

case presentation includes what

Answer 2

• presentation of possible tx options like risk and benefits
• honest explanation of all possible things that could happen before you start the tx
• pt must have all questions answered before tx is accepted
• pt must understand and sign informed consent before tx begins and before anesthesia on pt

Question 3

the 7 iatrogenic misadventures

Answer 3

1. wrong tooth (commission)
2. missed canals (omission)
3. separated instruments
4. ledging, blockage, and transportation apical perforation
5. blow outs
6. short and long fills
7. perforations and strip perfs

Question 4

what to do if you did the wrong tooth

Answer 4

1. leave the room and compose yourself
2. compensate pt
3. take responsibility

Question 5

bulls eye indicates

Answer 5

a 4th root and 4th canal DL. (difficult)

especially in NA and some asian pops

Question 6

4 approaches for when your file separates

Answer 6

1. remove the instrument (refer)
2. bypass the instrument
3. apical surgery and retrofill
4. TE and alternate tx options

choose the one that is best for the pt and the tooth.

Question 7

file separation tx decision and prognosis depends on what

Answer 7

• the location

- if the canal has been cleaned, shaped, disinfected and filled.

Question 8

if you start seeing that you have blockage what should you do?

Answer 8

• stop, irrigate, recapitulate with a #10 file and try to take a file again

Question 9

how do blow outs occur

Answer 9

you messed up WL
no you have no ACZ (apical constriction zone)

tooth is now compromised

Question 10

what to do if you have a blow out

Answer 10

1. re-establish a new apical stop within the root
   a. back off the WL and shorten it and enlarge if possible
   b. surgical resection and retroseal
   c. extract and replace

Question 11

if you have a long fill what should you do

Answer 11

1. defective apical control zone
2. cannot predictably retrieve GP beyond apex
   no good NSRCT option bc surgery will be necessary
   good reason to do tree stage XR

Question 12

if you have an anemic or short fill what should you do

Answer 12

1. remove old GP and filling material
2. re-shape to correct length and shape if possible
3. obturate correctly before someone else sees it

Question 13

the mother of all iatrogenic misadventures

Answer 13

perforations

the hardest to repair and the most damaging

Question 14

commonly seen reasons for perforations

Answer 14

1. failure due to angulation of long axis of the root
2. failure to measure and stay short of furcation
3. failure to remove adequate extra-coronal restoration to clearly visualize pulpal landmarks
4. spatial disorientation with inadequate access

Question 15

clues to recognition you have perforated

Answer 15

• unexpected hemmorrhage
• no mark on the 7mm on the bur
• loose and sudden drop-through
• unusual file angle
• pain is NOT a reliable clue

Question 16

once you have recognized you perforated what should you do

Answer 16

• stop and do not enlarge

- use apex locator

Question 17

how to control hemorrhage of a perforation

Answer 17

• with paper points or cotton carefully
• hemostatic agents
• non-invasive observation
• determine extent of damage
• dilute with a different [ ] of NaOCl now 10:1
• NO PRESSURE

Question 18

perforation prognosis depends on what 3 things

Answer 18

extent
location (close to attachment = worse)
timing of repair

Question 19

why should you do an immediate repair with perforation

Answer 19

because infection and loss of bone occur very rapidly

Question 20

what should you do to RCT you started as you refer it to an endo

Answer 20

• disinfect with 0.8%. NaOCl
• protect the found canals with removable material
• create an easily removable temp using CAVIT
• seal the tooth with a secure temp filling over cotton
• refer at once PRN

Question 21

removable material to use

Answer 21

cotton
paper points
Gp
file

Question 22

how will an endo repair the perforation

Answer 22

collacote -> matrix for repair
MTA is placed over the perforation and set with water.
once its closed, finish off the RCT

Question 23

subgingival perforation vs supragingival perforations

Answer 23

subgingival is worse bc of bacteria

Question 24

if you perforated below the alveolar crest what should you pack with

Answer 24

MTA

Question 25

if you perforated above alveolar crest pack with

Answer 25

geristore

Question 26

what is the most difficult perforation to repair

Answer 26

strip perforation bc large instrument is misdirected or was aggressively used

Question 27

apical perforation

Answer 27

starts with a ledge

added pressure leads to a root perforation well below attachment

try to bypass ledge re-enter canal and obturate canal

fill perf with GP or MTA then SEAL canal permanently