Locating entrance - managing blockage

Fig. 1

Preoperative radiographic analysis

This is a referred case as a reason of inability to negotiate the canal of tooth no. 12 to full length.

From the coronal section of CBCT, it was evident the presence of periapical lesion  with no canal could be seen apically.

As a rule, the presence of periapical lesion is an indication of patent canal apically.

Fig. 2

CBCT analysis

By examination of more CBCT cuts it seems like the prior attempt to locate the canal entrance or the canal path failed as a reason of misalignment of used tools either ultrasonics or files.

So the site of the canal looks to be more mesial and more buccal to the previous reduction site.

In the axial cut is confirmed the obliteration of the canal at the level of blockage.

Fig. 3

clinical intervention

After removal of old temporary filling, calcium hydroxide dressing was detected. 

It was great to have a radiopaque material inside the canal to trace the previous site of reduction and troughing.

Fig. 4

Removal of canal dressing.

Old calcium hydroxide removed with active irrigation with ultrasonics.

At this stage the use of magnification is very important for precise more conservative reduction

Fig. 5

identifying the site of the canal

The red circle represent the site where the canal should exist which is more buccal and more mesial to the previous reduction site.

Fig. 6

locating the catch

The site of the canal located with the use of magnification and ultrasonics and here comes the role of C file to negotiate the canal.

As the canal is tight and narrow the use of C file is recommended to avoid buckling and bending effect of K files.

C files from Fanta are made of high quality stainless steel which is heat treated to make it more stiff for easier negotiation to the narrow canal

Fig. 7

Negotiation to full lenegh

Canal negotiated to full length using C files with the help of EDTA solution

Files used were 10,12 from Fanta C files.

Working length determined using apex locator but we need to take care and double confirm that this is the canal path not a superimposed perforation thats why shifting the X-ray cone mesial and distal would be preferred as a confirmatory step

Fig. 8

Double check and confirming the canal path

Mesial and dista shift radiographs were taken confirming its the canal and its not a perforation.

The relation of the file with the root didn’t change, the file is always in the middle of the canal with different cone shift and angulation.

If there is any difference in the relation that would be an indication of superimposed perforation

Fig. 9

Canal shaped and obturated

Clinical image showing conservative shaping and obturation to the canal.

Fig. 10

Radiographic workflow

Final radiographs of MC fit and obturation showing sussessful management of the case with conservative approach.