Fig. 1

Initial situation of lower 1st Molar with large gingival polyp presented with spontaneous pain

Fig. 2

Pre-op X-Ray showed deep carious lesion with periapical radiolucency

Fig. 3

Excessive gingival tissue removed by thermacut bur. The bur will cauterise the gingiva when cutting on high speed without the water spray

Fig. 4

This figure shows bleeding from the gingiva due to cutting of gingival polyp 

Fig. 5

Gingival polyp was removed as a one piece

Fig. 6

This figure shows complete removal of gingival polyp, and tooth ready for isolation

Fig. 7

Isolation with rubber dam for pre-endo buildup, clean margin all around the tooth

Fig. 8

All carious tissue was removed and Access opening was made through the pulp chamber, a proper access cavity preparation is of central importance in localizing the orifices of the root canals

Fig. 9

Orifice opener to remove the coronal pulp tissue and to enlarge the canals orifices

Fig. 10

Removal of necrotic pulp tissue from the canals 

Fig. 11

Starting the build up, using Circumferential matrix in order to restore the missing walls

Fig. 12

Pre Endo-buildup was done, and the tooth is ready for the next visit 

Fig. 13

Temporary filling, End of the first visit

Fig. 14

Second visit, single isolation for accused tooth

Fig. 15

Working length determination for the four canals 


Fig. 16

Shaping of the canals

Fig. 17

Searching for extra canal by manual file

Fig. 18

Cleaning of the isthmus by ultrasonic tips

In most of the cases, middle mesial canal is hidden by a dentinal projection in the mesial aspect of pulp chamber walls, and this dentinal growth is usually located between the two main canals (mesiobuccal-mesiolingual)

Fig. 19

MM (medio-mesial canal) was catched

The additional canal was explored with a no. 10 K-file

Fig. 20

No.10 K-file was separated during the negotiation of MM

Fig. 21

Ultrasonic tip to remove the separated instrument

Fig. 22

Separated instrument jumped from MM to Distal canal during removal

Note: I should have closed each canal orifices by teflon or liquid dam in order to prevent this mistake 

Fig. 23

Separated file was successfully retrieved by ultrasonic tips

Fig. 24

X-Ray to Confirm the complete separated instrument removal

Fig. 25

Three files in mesial canal system 

ML , MM , MB

Fig. 26

Final working length determination 

Apical gauging

Apical gauging is a technique to best determine the size of the apical constriction and the taper of the apical portion closest to the foramen.

Apical gauging helps with:

1. Choosing the best master cone that closely matches canal length and taper

2.Achieving true tug back – as opposed to false tug back!

3.Minimising GP extrusions during obturation, especially with warm vertical compaction/condensation.

How do you do apical gauging?

Establish the depth of apical constriction – this is the zero reading on your apex locator. Remember your working length will be 0.5mm – 1mm short of this.

After cleaning and preparing the canal system to your working length, passively insert 02 taper hand files, starting from #15. If the file goes past the apical constriction (your working length + 0.5-1mm), then choose the next largest file and repeat.

When a file passively binds short of the apical constriction, that will be the upper limit of the apical constriction diameter. The smaller file before that would be the lower limit.

Fig. 27

Apical foramen size for the canals was

#25 for MM

#35 for MB

#40 for ML

#60 for DL

Fig. 28

Adjust the gutta percha point size according to the apical foramen size that we take from apical gauging 

Fig. 29

Cone fit it should be checked with wet canal not dry, so it work as lubricant in side the canal as the sealer work 

Fig. 30

Starting Irrigation protocol 

5.25% NaOCL 

17% EDTA 

2% CHx 

With different time for irrigation 

Fig. 31

Warming of sodium hypochlorite in order to increase its activity by obturation pen

Fig. 32

Activation of irrigant solution by ultrasonic 

Fig. 33

Sodium hypochlorite in action

Fig. 34

Clean and Ready for obturation

Fig. 35

Obturation by continuous wave of condensation technique (CWC)

Fig. 36

Down pack

Fig. 37

Down pack by x-ray

Fig. 38


Fig. 39

Coronal seal with flowable composite 

Fig. 40

Final restoration after finishing, polishing and occlusal check

Fig. 41

Post-op X-Ray

Fig. 42

The Author:

Dr. Abdulwahab Al-Qaraghuli

Baghdad - Iraq

2018: B.D.S (Baghdad University)

2021: M.Sc. student (Mustansiriyah University)

2020: Best case of the year at StyleItaliano Endodontics Facebook group


Mandibular molars demonstrate considerable variations with respect to number of roots and root canals. The possibility of additional root canals should be considered even in teeth with a low frequency of abnormal root canal anatomy. 

treating additional canals may be challenging, but the inability to find and properly treat the root canals may cause failures. Information on root canal anatomy come from radiographs is valuable and should always be integrated with a careful clinical examination, preferably under magnification for the better and successful endodontic treatment.


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