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Odontogenic Sinusitis Symptoms & Diagnosis

Author Julia Casazza covers Odontogenic Sinusitis Symptoms & Diagnosis on BackTable ENT

Julia Casazza • Nov 8, 2023 • 42 hits

What is odontogenic sinusitis (ODS)? How does it differ from chronic rhinosinusitis? Why do otolaryngologists need to keep it on their differential? When dental disease spreads to the maxillary sinus, ODS results. Patients experience unilateral sinusitis symptoms and report foul-smelling odors. Rhinologist Dr. John Craig of Henry Ford Health recently joined BackTable to discuss contemporary management of and research on this neglected, but common, condition.

This article features excerpts from the BackTable ENT Podcast. We’ve provided the highlight reel in this article, and you can listen to the full podcast below.

The BackTable ENT Brief

• As the name suggests, ODS is chronic sinus disease of dental origin. Sinus disease can persist even after improvement in dental pathology.

• Diagnosis of ODS can be difficult when disease persists after dental work, as the culprit tooth is no longer present. Accordingly, otolaryngologists should maintain a high index of suspicion for ODS in all sinusitis patients, particularly those with unilateral disease.

• On a physical exam, ODS can present with fistulae between the oral cavity and maxillary sinus. The scope exam will reveal “angry” appearing maxillary sinuses containing pus and occasional polyps polyps.

• CT sinus without contrast is the best imaging study for ODS. Dental imaging studies (such as Panorex) are of limited benefit.

Odontogenic Sinusitis Symptoms & Diagnosis

Table of Contents

(1) History & Symptoms Suggestive of Odontogenic Sinusitis

(2) Physical Exam Findings in Odontogenic Sinusitis

(3) Imaging Findings in Odontogenic Sinusitis

History & Symptoms Suggestive of Odontogenic Sinusitis

While ODS presents with sinusitis symptoms, the presence of foul-smelling drainage and unilateral disease differentiate it from other forms of sinusitis. Most patients complain of chronic symptoms; the median symptom duration at presentation is six months. As in other forms of sinusitis, patients report some or all of the following: nasal obstruction, anterior drainage, posterior drainage, facial pressure, and anosmia. A history of previous dental work (fillings, root canals, extractions, implants, and bridges) may be present, though few ODS patients are referred from dental providers. For this reason, otolaryngologists should keep this diagnosis in mind when evaluating a new sinusitis patient.

[Dr. Ashley Agan]
When patients are coming in, can you talk to us about the stereotypical patient that comes in that you're seeing that ultimately has ODS? Obviously, not everybody is the same, but you've mentioned the foul smell. Is there anything else in the history that tips you off to thinking that it could be ODS?

[Dr. John Craig]
Yes, I think first off, people just have to flip a switch in their head that this is more common than most people think, and once you start thinking about or looking for it, you find it more. I know that sounds obvious, but the problem is that all of these patients will have the cardinal sinusitis symptoms to some variable frequency. They're going to have nasal obstruction, they're going to have anterior drainage, posterior drainage, facial pressure, sometimes smell loss, and different permutations of all those symptoms. The symptomatic history by itself doesn't say, oh, it's definitely dental. If you happen to remember to ask about foul smell, which is not one of the cardinal symptoms in all national-international guidelines, then you might pick up on that. The other thing is unilateral. I've noticed, reading a lot of doctors' notes, they're all-or-none symptoms. Instead, you need to know whether that nasal obstruction is one-sided or both sides. Is the colored drainage one-sided or both sides? It's just been interesting to me noticing that not everyone asks that simple question. Try to focus in on what's unilateral or bilateral, and then that foul smell will be a little extra in terms of suspicion.

[Dr. Ashley Agan]
How common is it for a patient to have associated tooth pain, jaw pain, gum pain?

[Dr. John Craig]
Intuitively, you'd like to hear that was a predictive symptom. Unfortunately, the studies that have included dental pain in symptomatic history in their data collection, it's been about 20% to 40% of these patients have dental pain. Now, I would argue, unfortunately, I don't think most people ask for one. Then the other problem is these teeth are usually necrotic or absent. They may have had their tooth pulled. For multiple reasons, either people aren't asking or they're just not painful etiologies, that symptom is not helpful. I actually always do ask because I collect as a data point, but unfortunately, it's not hugely helpful.

Listen to the Full Podcast

Odontogenic Sinusitis with Dr. John Craig on the BackTable ENT Podcast)
Ep 126 Odontogenic Sinusitis with Dr. John Craig
00:00 / 01:04

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Physical Exam Findings in Odontogenic Sinusitis

Close examination of the oral cavity and sinuses cinches the odontogenic sinusitis diagnosis. On examination of the oral cavity, look for evidence of prior dental work, especially extractions. The first and second molars are closest to the sinus floor. Infection involving these teeth confers higher risk of ODS. Assess the health of tooth roots, including fullness of and pus at the tooth socket. Slide a small probe along the gingiva to assess for fistulae. Upon scope examination of the sinuses, patients with ODS will have unilateral disease, sometimes with polyps and severe edema. If pus is present, it should be cultured; presence of oral flora supports the diagnosis of ODS. When questions about dental health arise, referral to a dental specialist (such as a periodontist) for vital pulp testing can provide complementary expertise.

[Dr. Ashley Agan]
Moving on to your exam, I assume you have typical rhinology exam where you're looking in the nose and you do endoscopy. When it comes to your exam, your oral exam, what are you thinking when you're looking at teeth? I know when I look in the mouth, I'm like, "Oh, that tooth looks kind of funny," or maybe I can't say that I feel very confident about what I see.

[Dr. Gopi Shah]
Are you tapping on any of the teeth with a tongue blade like checking for loose – feeling the gums?

[Dr. John Craig]
These are all really important questions and we don't have answers for them yet. Again, I'm going to go to my anecdotal oral exam process, but I can tell you it does not predict ODS in either direction. If I see a diseased tooth, frankly, necrotic, horrible-looking tooth, totally clear sinuses. Then the flip side is true, really healthy-looking dentition, we get the scan, and oh my gosh, it's a huge periapical abscess, bone erosion into the sinus. Unfortunately, for me so far, I just haven't studied it methodically, but I don't think there's a clear correlation between the oral exam and the sinuses.

What do I actually look for? I do look for prior dental work because it just makes sense to me that if they've had something done that affects the possible spread into the pulp chamber, then that's going to increase the risk for sinusitis down the road. If they've had a prior extraction, I'm looking at that. I should mention that the molars are the main culprits here. It's actually going to be a cool study that we haven't put out yet, but looking at the relationship of the tooth sockets to the sinus, the first and second molars are generally closest to the sinus floor.

They're the highest-risk teeth basically regardless of dental pathology. Either endodontic pathology with intact teeth or prior extractions causing a fistula, those are your biggest bang for your buck. I tend to look at the posterior dentition. That said, we've all seen a first or second premolar also cause disease and in a very rare situation, a canine. I'm looking at all those teeth mainly just to try to correlate to what I'm going to see on my endoscopy. I mentioned prior dental work. Overt dental disease obviously is suspicious. Necrotic tooth that's fractured, black looking, and then don't forget to look at the gum line.

Right above the tooth roots, if there's a raging dental process, there will be fullness there. You also might see pus straining through the tooth socket. I think those are the main things I'm looking for. Then, like you mentioned, the scope. The scope is huge.

Imaging Findings in Odontogenic Sinusitis

Non-contrast sinus CT is the imaging test of choice for odontogenic sinusitis. On CT, ODS appears as a subtotal or total opacification of the maxillary sinus. Sinus walls often appear hyperostotic. Mucosal inflammation may cause the uncinate process to bulge out. In extensive disease, erosion into the orbit or skull base is present. Associated dental pathology appears as a peri-apical lesion with surrounding bone erosion. If the differential includes a tumor or if bone erosion is present, MRI is indicated. Dental x-rays (Panorex) are not recommended.

[Dr. Ashley Agan]
Before we get to Panorex, what are your typical CT findings? Is it a hyper-expanded max that's blown out or in the uncinate, it's going to be sucked in laterally to the lamina? What is your typical findings for this on the unilateral and the max?

[Dr. John Craig]
Yes. Subtotal to total opacification of the maxillary sinus is going to be most common. This actually is a nice segue into the mucosal thickening dilemma. One point I want to hit on a couple of times during this today is that mucosal thickening adjacent to dental pathology or dental work is not what we're talking about with odontogenic sinusitis. Unfortunately, the literature lumps it in there sometimes. That's a problem. That's just reactive mucosal inflammation to underlying dental pathology responds very well to dental treatment.

A true infectious ODS, like we're focusing on for the most part, you won't see an atelectatic sinus. You'll definitely see bulging out of the uncinate process. There's actually a nice study by Alberto Saibene, out of Milan, actually. He published a study showing that the angulation of the uncinate bulges out more in ODS. You'll see that in the maxillary. Then, in my practice, you usually see some extension of the ethmoids plus or minus frontal. I think this is an important point. You usually see relative sparing of the posterior ethmoid and sphenoid sinuses. Infection drains in the middle of the meatus, presumably then can access the anterior ethmoid. Some patients, it's like the 5% range for my practice, get into the posterior ethmoid and sphenoid. It's possible, it's just a lot less common.

Podcast Contributors

Dr. John Craig discusses Odontogenic Sinusitis on the BackTable 126 Podcast

Dr. John Craig

Dr. John Craig is the chief of Rhinology and co-director of the Skull Base Center at Henry Ford Health in Detroit, Michigan.

Dr. Ashley Agan discusses Odontogenic Sinusitis on the BackTable 126 Podcast

Dr. Ashley Agan

Dr. Ashley Agan is a practicing ENT and assistant professor at UT Southwestern Medical Center in Dallas, TX.

Dr. Gopi Shah discusses Odontogenic Sinusitis on the BackTable 126 Podcast

Dr. Gopi Shah

Dr. Gopi Shah is a practicing ENT at UT Southwestern Medical Center in Dallas, TX.

Cite This Podcast

BackTable, LLC (Producer). (2023, August 29). Ep. 126 – Odontogenic Sinusitis [Audio podcast]. Retrieved from

Disclaimer: The Materials available on are for informational and educational purposes only and are not a substitute for the professional judgment of a healthcare professional in diagnosing and treating patients. The opinions expressed by participants of the BackTable Podcast belong solely to the participants, and do not necessarily reflect the views of BackTable.



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