Fig. 1

Initial radiograph shows deep DISTAL CARIES related to tooth 14, as patient was suffering from pain

Fig. 2

 Canals negotiation to obtain glode path,  as you can notice 3rd file was introduced thinking it's LATERAL canal then it turned out it's a split of second canal buccally.

Fig. 3

Different angulation

Fig. 4

Intra oral microscopic view shows the split under magnification 25 X

Fig. 5

due to difficulty of inserting 2 guttapercha all at once in split , one has to be introduced first and vertically compacted allowing enough space for the other one to be followed.

Fig. 6

as you can notice one has been compacted while manual file inserted in the other split to avoid any unnecessary blockage by gp

Fig. 7

Final obturation

Conclusions

Root canal morphology of the maxillary first premolar appears with different variations, including root diameter, root canal diameter, canal wall thickness, canal diameter, and cross-sectional root canal shape.

The majority of maxillary first premolars have two canals. Of the 2 roots with 2 canals maxillary first premolars, the furcation groove on the palatal aspect of the buccal root has a great influence on the treatment and prognosis .

Thus , to obtain predictable result we have to dedicate plenty of time for radiograph interpretation not to mention requiring CBCT whenever needed .

Bibliography

Pécora JD, Saquy PC, Sousa Neto MD, Woelfel JB. Root form and canal  anatomy of maxillary first premolars. Braz Dent J. 1992;2(2):87-94. Pubmed PMID: 1290917.

Gupta S, Sinha DJ, Gowhar O, Tyagi SP, Singh NN, Gupta S. Root and canal morphology of maxillary first premolar teeth in north Indian population using clearing technique: An in vitro study. J Conserv Dent. 2015 MayJun;18(3):232-6. Pubmed PMID: 26069411.

Hargreaves KM, Cohen S, Berman LH. Cohen's pathways of the pulp. 

Mosby Elsevier,; 2011.

[4]. Jayasimha Raj U, Mylswamy S. Root canal morphology of maxillary

premolars in an Indian population. J Conserv Dent. 2010 Jul;13(3):148-51. 

Pubmed PMID: 21116391.