This is a great case with merging canals treated by Dr Xander Howell.
This interesting case with merging canals in both the mesial and distal roots (Vertucci Class II)
This patient was referred in for completion of primary endodontic therapy. The first stage of treatment was to remove any decay from the back of the tooth and seal the space with a white composite filling material to ensure no new bacteria could enter the pulp system. During the initial cleaning and shaping appointment 4 canals were noted (ML, MB, DL and DB). During irrigation it became apparent there was a merging of both of the distal canals as in a dry canal, irrigation of the DL canal flowed back out of the DB canal. Subsequent investigation showed they merged at around 13mm
The merging of the mesial canals was picked up following establishing full working length with an apex locator. The ML canal was prepared with a Reciproc 25 to full length. A single GP point is placed in the canal and then a size 10 file passed to full working length in the MB canal. Inspection of the GP point showed a clear mark from the size 10 file 2mm short of the apex - therefore the WL of the MB canal was modified and reduced by 2mm. This reduces the risk of damage of the apical constriction.