How Long Does It Take for a Periapical Lesion to Develop?

How long does it take for a periapical lesion to develop? This is a great question, and it’s the topic for today’s tooth story.  

The patient in this case was a young lady who came to my office needing a few root canals. She had some deep decay on teeth #19 and 20 (and even some decay starting on #18).

I started with an endodontic diagnosis.

None of her teeth had any response to cold, and #19 was slightly tender to percussion. #20 had normal percussion. 

So, my endodontic diagnosis was Necrotic pulp and Symptomatic Apical Periodontitis #19 and Necrotic Pulp and Normal Apical Periodontium #20.

Notice that there is no lesion on tooth #18 at this time.  

I start with the  caries excavation. After that, I was in the pulp chamber.

Personally, I like to do my root canals one at a time. I could have easily done these together, but my patient was a bit apprehensive, so I took that into consideration and treated the teeth one at a time.

Here are the working radiographs from #19. We treated this tooth first, since it was more symptomatic. Using the SLOB rule, I was able to really visualize my four canals during treatment. 

Then, I treated tooth #20.

After this, she went back to her dentist to restore and stabilize these teeth. 

But that wasn’t the end of the story. About 3 months later, she came back to me because now #18 was starting to bother her.  

You can see there is new periapical radiolucency there, and it is pretty significant. There is even some furcal breakdown.

What does that tell us? The bacteria from her cavity has gotten into the pulp and killed the nerve. The tooth no longer felt cold and was tender to percussion. The diagnosis is Necrotic Pulp and Symptomatic Apical Periodontitis #18.

So, how long does it take for a periapical lesion to show up?

Not very long at all, sometimes!

I saved this case for y’all because I thought it was interesting just how fast her tooth shifted.  Her tooth went necrotic and she had a significant amount of bone loss in just 3 months! I think that is pretty damn fast.

She clearly has a high caries risk, and perhaps this is the reason why everything progressed so quickly. We don’t really know why this happened so fast. But I want to make sure you know that periapical lesions can show up in not long at all. Human bodies are wild! And moreover, it can really have an impact on your treatment.

What’s the takeaway from this? It is very important to take that preoperative periapical radiograph before you do that crown or restoration, so you make sure that you are not restoring a necrotic tooth. 

This is one of the main reasons that I am not a fan of insurance companies dictating what kind of radiographs we take, and when. The system doesn’t actually work with the reality of our bodies. Let me explain.

A note on insurance…

When insurance companies only pay for bitewings, many patients refuse other radiographs. And that leaves us dentists high and dry, because we cannot make a proper diagnosis. 

And if we go by just our bitewing radiographs, then we may end up placing a crown on the tooth that needs a root canal first and then we have to drill through that brand new crown to do the root canal. 

The result? We get a very unhappy patient who then wants a new crown at no charge. See how this can snowball?  

So, when it comes to getting all the information you need in order to get a proper diagnosis, I say stand your ground and do what you have to do. Take the radiographs that you need. 

Don’t let the patient or an insurance company tell you what to do. Explain to your patient that you really must have additional imaging to feel confident in your diagnosis and treatment plan, and to do your best for them. 

Don’t let anyone or anything sway you from being consistent.

Don’t forget to get paid!

Make sure you charge for your work, your technology, and your training. When you don’t charge for things, you decrease the value of it, in the patient’s eyes.

For example, when an insurance company refuses to pay for a radiograph that’s anything other than a bitewing, why should you eat the cost?

Really, your only option is to charge the patient for that service. However, when you explain that this is an investment in their health that can save them from having a future retreatment or complication (which will end up being even more expensive), they’ll often be glad to pay the additional imaging fee.

If there was one thing that I wish all patients understood about their insurance, it’s this: Their insurance company is the one not covering the procedure, and it has nothing to do with the provider giving the care. The more we take the time to educate our patients about the ins and outs of dental insurance, the better it will be for everyone involved.

The diagnosis stage is so important.

If you’re dealing with a case where you’re wondering, how long does it take for a periapical lesion to show up, I want to remind you that this is why it is SO important to do your endodontic diagnostic tests thoroughly prior to your restorative procedures.

You always want to be sure that you know the pulp status of your teeth prior to treating those teeth, even if it is just for a simple filling. Consistently doing your endodontic testing prior to restorations will prevent these unwanted moments and, therefore, reduce your number of unhappy patients.

This is another way that I see endodontics being so important in the general practice office.  It sneaks into your office in so many ways, and that is exactly why I say you are doing endo more often than you may realize! Endo is so much more than root canals.

If you want to see the power endodontics can have in making your practice run smoother, reduce your chair time, create more efficiencies, and lead you to better outcomes, check out my award-winning endodontic CE program, E-School. Enrollment is open now!

– Sonia