Friday, December 21, 2012

Lateral Portals of Exit

As clinician readers know, the canal anatomy of teeth is rarely simple. Lateral portal of exits (lateral canals) are a significant challenge to clean and are present in many of the teeth we see for root canal therapy. In a previous post, I discussed the use supplemental irrigation and ultrasonic instrumentation to clean isthmus tissue. That post can be found here: I use these same techniques to address lateral portal of exits. These lateral exits are very common, but with proper irrigation, they can be predictably addressed.

Sometimes, as in this #19 below, the exit can be found at the apex in the form of a sharp distal turn or delta. Direct instrumentation may or may not be possible with small, pre-bent files (6 or 8).

These exits can also be found in the furcation region. If untreated and contaminated with bacteria, they can feed furcation radiolucencies and cause attachment loss (probing). Here is a straightforward #30.

Untreated, you will see radiolucencies centered on the exit as in this #9 retreated below. I measured to the depth of the lateral canal and focused my irrigation and irrigant activation at that level.
Always be aware that the potential for more anatomy exits. With this #28, I found 3 canals splitting at midroot and thought I had found all the anatomy. Fortunately, extensive irrigant activation picked up a lateral exit off the mesial buccal canal in the apical third. Tooth #29 is scheduled for retreatment.

In summary, do not believe for a second that sticking a file in a canal completely cleans a canal system.
Merry Christmas!
Justin Parente
Alpharetta Endodontics


Unknown said...

If I ever have a root canal that looks like your #28, I'm putting on my Christmas card. Beautiful work. You should be very proud of that.

Nicholas Calcaterra DDS said...

That #28 is textbook. And even more impressive you preserved the 28/29 splinted crowns. Great work.