Failed Dental X-Rays: What To Do When Radiographs Aren’t Enough

Many of us got into the practice of dentistry because we wanted to help people. Speaking from personal experience, it was an endodontist who got me out of months-long oral pain and back to living a fuller life when I was in college. But that aspiration to help people can make it all the more frustrating when a patient comes to us with tooth pain, but nothing shows up on the x-ray.

How do we arrive at the right diagnosis and treatment plan for our patients when there’s a failed dental x-ray (i.e., limitations to what the x-ray can show us) and not enough information coming from diagnostic tests alone? I’ve got some ideas, but let me start by sharing a tooth story that will set the scene for my proposed solution. 

The Tale of a Failed Dental X-Ray

Our dental x-ray failure story starts with a 56-year-old female patient whose official diagnosis was Necrotic Pulp and Asymptomatic Apical Periodontitis (read a little more on pulpal and periapical diagnosis here). She was referred by her dentist after a heavy dose of pain meds and some antibiotics. By the time I saw her, she couldn’t indicate which tooth was giving her trouble.

This is what her preoperative radiograph looked like. As you can see, we’re not getting much!

Now, at this point in my career, it’s quite a normal occurrence to have radiographs that give me no signs of what’s to come. X-rays have limitations after all, and it’s important for us to understand what they are! Yet despite the failed dental x-ray, the patient is still in pain—just like this poor woman here.

With nothing to go by from the periapical radiographs, I had my work cut out for me. Time to put on my detective cap!

After conducting a full set of diagnostic tests, I found that teeth #2-5 had no pain to percussion, and the only tooth in the quadrant that felt cold was tooth #2 (#3-5 had no response to cold). I couldn’t assume that all three teeth were necrotic, so which tooth was it? The patient described having a few days of excruciating pain and then it started to subside. Her claim of having a painful episode like this one is usually a sign that a nerve has died somewhere, but I needed proof in order to proceed with treatment.

Any idea what I did next?

Getting an Accurate Diagnosis After Dental X-Ray Failure

We all know that periapical radiographs can be great—except when they’re not. When a patient comes in with tooth pain, but nothing shows up on the x-ray, it can be a nightmare for diagnosing accurately.

By this point, I was frustrated and the patient was frustrated—so I opted to employ my secret weapon: the good ol’ cone beam. 

Without my cone beam, I would have had to wait for my patient’s pain to return and localize. But instead, I could now see right through the buccal bone, without waiting for the bony breakdown of the cortical plate to occur. That meant that I could figure out what was going on, treat this patient right away, and finally relieve her pain.
To determine the etiology of the patient’s pain. I looked carefully through the planes, seeking any irregularities in the teeth and any resorption of bone. Everything looked normal… until I got to tooth #3. I could see a small radiolucency around the disto-buccal and palatal roots.

You can see the thickened sinus membrane in the next image as well (green arrows). This was the sign I needed that it was tooth #3 that was necrotic. Despite all the difficulties in getting there—from the failed dental x-ray to the patient’s spreading pain—I gave her a confident diagnosis and told her that we could proceed with treatment right away.

CBCT as a Solution for Failed Dental X-Rays

I’m a very thorough tester—which counts for a whole lot! And this is a clear example of a case where the traditional methods just didn’t cut it. (I mean, compare those first radiographs to what showed up using the cone beam!)

I’m embracing the technology of CBCT because it helps me correctly diagnose my patients and expedite their healing journey, especially when there’s dental x-ray failure and the normal diagnostic tests just don’t give me enough to go off of. In particular, cone beam imaging helps me:

• Reveal the true etiology of root canal failure (like the patient in this tooth story!)
• Determine the true size of lesions
• Locate hard-to-find canals like the MB2 in maxillary molars
• Facilitate the early detection and diagnosis of disease
• Communicate with patients and educate them on root canals

And so much more!

I know the CBCT isn’t foolproof (see my blog on cone beam and cracks), but it does help me diagnose cases more accurately every day and get my job done—and that job is to save teeth!

Boost Your Diagnostic Skills With My Free Checklist

The CBCT is a fantastic tool for facilitating diagnosis, especially when dealing with a failed dental x-ray. But in many cases, you can still make accurate diagnoses and treatment plans using traditional methods! 

You can make sure your skills are up-to-par by downloading my free Pulpal and Periapical Diagnosis Checklist. It’s a cheat sheet to help you diagnose and treat patients correctly—every time.

– Sonia