Fig. 1

Pre-op X-Ray showed lower first premolar with defective amalgam filling with distal cavitation, and there is fast-breack phenomenon.

In this type of configuration there is expectation of extra anatomy and deep apical split of the canal.

Diagnostic radiograph revealed there is slight periapical change. 

Fig. 2

Negotiation of the canals.

There is deep apical split of the main canal into one lingual and one buccal canal

Noticing the buccal canal go slightly mesially this indicated may be there is more extra-anatomy in the distobuccal side especially when the buccal canal is more tinny than the lingual one.

Working length was determined by apex locator and confirmed by x-ray for all the canals..

Fig. 3

With distal shift and bending of the K-file #10 scouting of the distobuccal canal..

So there is one lingual and two buccal canals

All the canals are patent.

Working length was determined by apex locator and confirmed by x-ray for all the canals.

Fig. 4

Shaping till the full working length 30/04 for all the canals and master apical cone confirmed. 

The shaping protocol :-

- coronal flaring with orifice opener file

  • D finder file # 10.
  • Rotary file 15/03
  • Rotary file 17/04
  • Rotary file 25//04
  • Rotary file 30/04

With copious amount of NaOCl 5.25% between each file, EDTA 1cc for all the canals with sonic activation for 1 minutes to remove the smear layer and followed again with NaOCl to disinfect again 

Fig. 5

The lingual cone bended to go through the lingual canal but the bending can’t preserved inside the root canal system because of the body temperature straighten the cone again.

Using dry ice (ethyl chloride) spray to increase the degree and duration of bending.

Fig. 6

Obturation of the canals by single cone with bioceramic sealer and down back of the cones.

Fig. 7

Filling of the middle and coronal part with heat softened gutta-percha by Fast fill with final composite filling.

Fig. 8

post-operative X-ray with final restoration.

Fig. 9

About the author:

Dr. Hussein Arshed graduated in 2012 from Mustansyria university in Iraq. 

  • in 2018, he got high diploma in Endodontics from Mustansyria university
  • In 2023, he got master degree in Endodontics from Mustansyria university
  • He works in Rivan dental clinic in Baghdad 
  • He has been offering lectures, training courses, webinars for dentists.
  • He is international lecturer and gives many lectures locally and internationally.
  • He is a fellow member of Style Italiano Endodontics.
  • He is key opinion leader for Avalon Biomed company in Iraq.


This case report presents the successful endodontic treatment of a mandibular first premolar with three Canals and provides a reference for other similar cases. Before starting root canal treatment it is essential to always consider variations in pulp anatomy and morphology. using magnification tools, to magnify the internal anatomy of a root canal increases the probability of finding additional canals. Using ethyl chloride spray is very beneficial in preservation degree of bending especially in case with deep apical split and curved canals.


1. Patel S, Dawood A, Ford TP, et al. The potential applications of cone beam computed tomography in the management of endodontic problems. Int Endod J. 2007;40(10):818–30

2. Zhang R, Wang H, Tian YY, et al. Use of cone-beam computed tomography to evaluate root and canal morphology of mandibular molars in Chinese individuals. Int Endod J. 2011;44(11):990–9.

3. Siqueira JF Jr. Aetiology of root canal treatment failure: why well-treated teeth can fail. Int Endod J. 2001;34(1):1–10.

Cohen S, Hargreaves KM. Pathways of the Pulp. 9th ed: St Louis: Elsevier Mosby; 2006. p. 216-7

4. Vertucci FJ. Root canal anatomy of the human permanent teeth. Oral Surg Oral Med Oral Pathol. 1984;58(5):589–99

Yoshioka T, Villegas JC, Kobayashi C, et al. Radiographic evaluation of root canal multiplicity in mandibular first premolars. J Endod. 2004;30(2):73–4

5. Yang L, Han J, Wang Q, Wang Z, Yu X, Du Y. Variations of root and canal morphology of mandibular second molars in Chinese individuals: a cone-beam computed tomography study. BMC oral health. 2022;22(1):1–12.