This week’s question is “Retreatment versus the apico – which to use, and when?” Watch my video explanation, and you can also read below. But definitely check out the case images in the video.
Do you ever have trouble deciding on when to do a retreatment versus an apico? When do you do what? What goes into your decision making?
Are you looking at the quality of the endo?
Are there any canal obstructions?
Are you using a CBCT to help make your decision?
Are you evaluating the restorative?
So think about it, What are your deciding factors? Well, let me walk you through my thought process.
The first thing that I do is I look at the quality of the endo and I try to find out the whole tooth story. Is there a missed canal? Can I tell if the previous operator achieved working length? Did they use a rubber dam? I like to show people the rubber dam so that they understand what I am talking about. When I show them this (see video) and ask if it was used during their treatment and they say no, they like to tell me that their root canal was done years ago and that is the reason why it wasn’t used. Well, my friends, the rubber dam was invented back in 1864, so there are no excuses. So, when I show them the rubber dam and they say that they have never used it, that tells me something. It tells me that the entire root canal could still be infected. And that could be the deciding factor for me on how I need to treat the tooth.
Let’s talk about the key differences between an orthograde retreatment and an apicoectomy. A retreatment will treat the entire length of the canal, while the apicoectomy will treat only around the last 6mm of the canal. So, if you suspect that the entire root is contaminated then a retreatment should be your first choice. And if you suspect a missed canal then retreatment should definitely be your first choice.
I also want to know when the tooth was treated and how many times the tooth was treated. When I was in dental school, I learned the following. You first do the root canal, if it fails you retreat it, if that fails then you retreat it again before you ever go to the apico. If the tooth has had only one root canal, then I will try to retreat whenever it is possible. I always try to do whatever I can non-surgically first. I have become sort of a retreat-o-dontist. One of the main reasons why I retreat first, is simply because and I have to be honest here, I just don’t trust that the tooth was disinfected properly or that there hasn’t been any coronal leakage. So, if there is a missed canal, a short obturation or a not so good looking endo, I retreat any chance I can get, and especially if it’s never been retreated before.
Apicos were created for a few main reasons. First is because teeth naturally have a lot going on in the apical third. There are times that in the last apical 3mm there are a lot of apical ramifications and isthmuses that can get in your way. The natural anatomy can sometimes be hard to disinfect. So when we do an apico we resect the tooth at 3mm because this is the level in which you will likely remove all those ramifications. We then do a retroprep that extends 3mm into the canal cleaning it even further and deeper and then seal it with a retro filling.
Another great reason to do an apico is if you have an obstruction, like a separated file or some calcification that prevented you from getting patent. The apico again would resect 3mm of the root, most likely exposing the file and then your retroprep would likely remove the file and clean in the area around where you can then seal the canal properly from the end.
Apicos are great and they work really well, but you have to know the right cases to use them because an apico will only achieve disinfection until around to the 6mm level, so if you suspect any coronal leakage or coronal contamination, then the contamination will not be addressed and could lead to a future failure like in this picture here (see video).
You can see that this patient had a silver point obturation that was likely failing and so the apico was done. Years later it started to fail and she developed a sinus tract because the entire length of the root was contaminated. So, another apico here was not going to fix this. Instead, I retreated it and her infection went away.
Here are a few more cases where some the apicos failed (see video). This root canal looks like it was done well, but it was tender to percussion again years after the apico. I wasn’t sure what was going on, but I knew that I would have retreated the tooth first prior to this apico so that was going to be my treatment of choice at this point. Now, my postop doesn’t look much different. You can’t tell much, but if you take an off-angle radiograph you can actually see that there is an extra canal in that root where the apico was done. You would never be able to see something like that unless you accessed it. So sometimes you have to take a peek inside to really know what is the correct treatment.
Here is another case that was apico’ed and was not healing. The CBCT here told us the exact story. There was a missed MB2. So an apico is not going to work long term when there is a missed canal like this. So, make sure you know the entire tooth story before you dive in. You have got to retreat first.
Another reason why people prefer an apico is sometimes for restorative reasons like in this patient here (see video).
I didn’t think that an apico is a good long term solution here because it doesn’t appear disinfected at all. And since the patient was ready to replace the crown and start over due to the esthetics, we went with the retreatment. But, you have to disassemble the tooth in order to get the job done. So make sure you talk to your patient and let them know their options and the pros and cons of each option. That’s what we did here and even though we both felt it was more work on the front end, we knew that it would give him the best result long-term both endodontically and esthetically.
Remember there are contraindications to both procedures, but specifically for the apico, you need to be careful for those special anatomical structures like the sinus and the mental nerve. And Sometimes the second molars can have too much buccal bone that it makes the surgery very difficult to access. So don’t forget to keep these contraindications in mind.
Now what about this? This patient has two posts, but she is asymptomatic and has been asymptomatic for 10 years. You could try to retreat the tooth, but this is a cast post and core and so you must consider that when you are treatment planning. You could certainly do an apico, but you can also do nothing. Remember another option is to do nothing, but don’t forget to follow-up your patient if this is what you choose.
Well, I hope this helps you make your decision making when it comes to retreats versus apicos. Both are great options to save your natural teeth.