Maxillary sinusitis is inflammation of the maxillary sinuses, the two largest paranasal sinuses, which sit inside the cheekbones above the upper teeth. It causes cheek pressure, blocked nose and aching upper teeth that worsen on bending forward. Most cases follow a cold, but a 2023 meta-analysis linked about half of CT-confirmed cases to the teeth.
For background, see the sinusitis hub and the full list of sinusitis symptoms.
What Is Maxillary Sinusitis?
Maxillary sinusitis is inflammation of the mucous lining of one or both maxillary sinuses, usually with trapped mucus behind a swollen drainage opening. It is the most commonly involved sinus in acute sinusitis, and it can also persist as chronic sinusitis.
Where the maxillary sinuses sit
Each maxillary sinus is a pyramid-shaped air space inside the upper jawbone (maxilla), behind the cheek and below the eye socket. The adult sinus measures about 3 to 4 cm in height and 3 cm in width and depth, with a volume of roughly 15 mL. The floor of the sinus lies directly above the roots of the upper premolar and molar teeth. The anatomy and functions of the maxillary sinus explain why this sinus is so often involved.
Why the maxillary sinus drains poorly
The maxillary sinus drains through a small opening, the ostium, located high on its inner (medial) wall. Mucus cannot fall out by gravity; tiny hair-like cilia sweep it upward toward the ostium and into the middle meatus of the nose. When a cold or allergy swells the lining around the ostium, mucus pools on the sinus floor, pressure builds and bacteria can multiply.
Acute, subacute and chronic forms
Duration defines three forms, according to the 2015 American Academy of Otolaryngology–Head and Neck Surgery (AAO-HNS) adult sinusitis guideline:
- Acute maxillary sinusitis: symptoms lasting up to 4 weeks
- Subacute maxillary sinusitis: symptoms lasting 4 to 12 weeks
- Chronic maxillary sinusitis: symptoms lasting 12 weeks or longer
- Recurrent acute sinusitis: four or more acute episodes a year with full recovery between them
What Are the Symptoms of Maxillary Sinusitis?
The hallmark symptoms of maxillary sinusitis are pain or pressure over one or both cheeks, nasal blockage, thick nasal discharge and aching upper teeth. Pain typically worsens when bending forward, lying down or stepping down stairs, because head movement shifts the fluid and pressure inside the sinus.
Cheek and facial symptoms
Five facial symptoms point to the maxillary sinus:
- Cheek pain or pressure, felt below the eye and beside the nose
- Tenderness when pressing on the cheekbone
- Upper tooth ache across several back teeth at once
- Pain spreading to the upper jaw, ear or eye socket
- Mild cheek swelling, occasionally
The page on facial pain or pressure covers how sinus pain differs from other facial pain.
Nasal and general symptoms
Maxillary sinusitis also produces the general signs of sinusitis: nasal congestion, thick yellow or green discharge from the front of the nose or down the throat, reduced sense of smell, bad breath, cough (often worse at night), tiredness and sometimes a mild fever. Discharge colour alone does not prove a bacterial infection.
One-sided symptoms
Symptoms confined to one cheek deserve closer attention. The 2022 state-of-the-art review of odontogenic sinusitis by Craig, published in the World Journal of Otorhinolaryngology – Head and Neck Surgery, describes a dental source as one of the most common causes of one-sided maxillary sinus disease. Persistent one-sided symptoms also call for a doctor to rule out a growth.
Is It Maxillary Sinusitis or a Toothache?
Maxillary sinus pain usually affects several upper back teeth on the same side and changes with head position, while dental pain usually centres on one tooth and reacts to hot, cold or biting. The two can also occur together, because an infected upper tooth can spread infection into the sinus.
| Feature | Sinus-related tooth pain | Dental (tooth) pain |
|---|---|---|
| Teeth involved | Several upper back teeth | Usually a single tooth |
| Lower teeth | Not affected | Can be affected |
| Effect of bending forward | Pain increases | Little change |
| Hot, cold or sweet triggers | Little effect | Often trigger sharp pain |
| Nasal symptoms | Congestion and discharge present | Usually absent |
| Course | Eases as the cold or sinusitis clears | Persists until the tooth is treated |
A dentist confirms or excludes a tooth source with an examination and X-rays. The article tooth pain and sinusitis: who’s to blame? covers this distinction further.
What Causes Maxillary Sinusitis?
Most maxillary sinusitis begins with a viral cold; bacterial infection, dental disease, allergies and structural blockages cause the rest. Each cause blocks the ostium or introduces infection into the sinus.
Viral infection
A common cold is the usual starting point. The virus swells the nasal lining, narrows the maxillary ostium and traps mucus. Viral sinusitis typically improves within 7 to 10 days, and the AAO-HNS guideline estimates that only 0.5% to 2% of viral episodes are complicated by a bacterial infection.
Bacterial infection
Doctors suspect acute bacterial sinusitis when symptoms last 10 days or more without improvement, or when symptoms worsen again after initially improving (“double worsening”). The bacteria most often involved are Streptococcus pneumoniae, Haemophilus influenzae and Moraxella catarrhalis.
Dental (odontogenic) causes
Odontogenic sinusitis is sinusitis caused by an infected upper tooth or a complication of dental treatment. Five dental sources are recognised:
- Apical periodontitis: an infection at the root tip of an upper molar or premolar
- Periodontitis: gum disease with bone loss around upper back teeth
- Tooth extraction: an opening between mouth and sinus (oroantral communication)
- Dental implants and sinus lift grafts: material displaced into the sinus
- Root canal treatment: filling material pushed beyond the root tip
The article on signs of sinus infection of odontogenic origin lists the warning signs of a dental source.
Allergies and structural factors
Allergic rhinitis keeps the nasal lining swollen, which narrows the ostium. Structural factors include a deviated septum, nasal polyps, enlarged turbinates and anatomical variations of the ostiomeatal complex. Cysts of the maxillary sinus are common incidental findings on scans and usually cause no symptoms.
How Common Is Odontogenic Maxillary Sinusitis?
A 2023 systematic review and meta-analysis estimated that 51% of maxillary sinuses and 50% of patients with maxillary sinusitis on CT had a dental cause.The review, by Vitali and colleagues in the Journal of Endodontics(2023;49(4):369-381), included 38 studies, 31 of them in the meta-analyses.
What the figure means
The 50% figure comes from CT-based studies that often assessed people seen in dental or imaging settings, and the included studies varied widely in design and definitions. It shows that dental causes are far more common than older textbooks suggested, not that every second person with cheek pain has a tooth problem. The review found that apical lesions, periodontitis and moderate to severe bone loss were significantly associated with odontogenic sinusitis.
Why the source matters
Odontogenic sinusitis often fails to settle with sinus treatment alone, because the infected tooth keeps reseeding the sinus. The Craig review states that evaluation and management should generally involve both an ear, nose and throat (ENT) specialist and a dental provider. The review also reports that complications occur in about 7% or fewer of published odontogenic cases, and 69% of those complications involve the eye socket.
How Is Maxillary Sinusitis Diagnosed?
Doctors diagnose maxillary sinusitis mainly from the symptom pattern, the duration and an examination of the nose and face. Scans are not needed for a typical acute episode; the page on how sinusitis is diagnosed covers the full process.
Clinical examination
The doctor asks about duration, “double worsening”, one-sided symptoms and recent dental work, presses on the cheeks, and inspects the nose. Nasal endoscopy, a thin camera passed into the nose, shows pus or swelling at the drainage pathway.
Imaging
A CT scan is reserved for chronic or recurrent sinusitis, suspected complications, one-sided disease or surgical planning. CT shows fluid, thickened lining, blocked drainage and dental root infections reaching the sinus floor. Plain X-rays are rarely used.
Dental assessment
One-sided maxillary sinusitis, a foul smell or taste, or symptoms after dental work call for a dental examination with X-rays or cone-beam CT to identify the tooth source.
How Is Maxillary Sinusitis Treated?
Treatment of maxillary sinusitis depends on the cause: supportive care for viral cases, antibiotics only for confirmed or strongly suspected bacterial cases, dental treatment for odontogenic cases and surgery for persistent structural blockage. Every medicine decision belongs with a doctor or pharmacist.
Supportive care
Four measures help most viral maxillary sinusitis:
- Saline rinses or sprays to thin mucus and clear the nose (see saline solution and sinusitis)
- Rest and fluids while the infection runs its course
- Warm compresses over the cheeks for comfort
- Sleeping with the head raised to reduce night-time pressure
Medicines
A doctor or pharmacist can advise on pain relievers, intranasal corticosteroid sprays and short-term decongestants based on age, other conditions and other medicines. Decongestant nasal sprays are limited to a few days, because longer use causes rebound congestion.
Antibiotics
Antibiotics do not help viral sinusitis. For uncomplicated acute bacterial sinusitis, the AAO-HNS guideline allows either watchful waiting with follow-up or an antibiotic, decided with a doctor. Unnecessary antibiotics add side effects and resistance, as discussed in too many antibiotics.
Treating a dental source
In odontogenic sinusitis, the dental source is treated through root canal treatment, extraction, removal of displaced material or closure of an oroantral opening. An ENT specialist decides whether sinus surgery is also needed.
Surgery
Surgery is considered for chronic maxillary sinusitis that persists despite medical treatment, for complications and for some odontogenic cases. Endoscopic middle meatal antrostomy widens the natural ostium through the nose; balloon sinuplasty dilates it; the older Caldwell-Luc approach through the gum is now rarely used. The article on techniques used for maxillary sinus surgery describes these options.
What Complications Can Maxillary Sinusitis Cause?
Complications of maxillary sinusitis are rare but include eye-socket infection, spread to the bone and, very rarely, spread inside the skull. The maxillary sinus roof is the floor of the eye socket, so infection can reach the orbit (see sinus infection and the eye).
Chronic disease
Untreated or recurrent inflammation can become chronic sinusitis with lasting congestion, loss of smell and poor sleep.
Oroantral fistula
A persistent opening between the mouth and the maxillary sinus after a tooth extraction lets fluids pass into the nose and keeps the sinus infected until it is closed surgically.
Tumours that mimic sinusitis
The maxillary sinus is the most common site of sinonasal cancer. Early tumours cause symptoms similar to sinusitis, so persistent one-sided blockage, bloody discharge, cheek numbness, loosening upper teeth or cheek swelling need prompt ENT review. The article on symptoms of maxillary sinus cancer covers these signs.
When Should You See a Doctor About Maxillary Sinusitis?
See a doctor when symptoms last more than 10 days, worsen after improving, recur several times a year or affect only one side. Recent dental work combined with cheek pain also warrants a dental and medical check.
Emergency warning signs
Seven signs need same-day emergency care:
- Swelling or redness around an eye
- Double vision, blurred vision or reduced vision
- A bulging eye or pain moving the eye
- A severe or unfamiliar headache
- Confusion or drowsiness
- Neck stiffness
- Fever above 39°C (102.2°F)
Who should seek advice earlier
People with diabetes, a weakened immune system, recent sinus or dental surgery, or a history of complications should contact a doctor early rather than waiting 10 days.
Can Nasodren® Help With Maxillary Sinusitis Symptoms?
Nasodren® is a nasal spray designed to relieve sinusitis symptoms by increasing drainage of retained mucus; it does not treat a dental infection and is not a substitute for dental or medical care.
Where Nasodren® fits
Nasodren® is a CE 0051 Class IIA medical device, not a medicine. Nasodren® is a 100% natural nasal spray made from Cyclamen europaeum extract, applied once daily into each nostril. It stimulates nerve endings (trigeminal) in the nasal lining and increases the drainage of retained mucus from the sinuses, including the maxillary sinuses. The extract is supported by more than 30 published clinical studies and a Level A recommendation in EPOS 2012.
Evidence and safety
A 2018 Cochrane review of the extract for acute sinusitis, covering 2 trials and 147 adults, concluded that its effectiveness is unknown because neither trial reported the review’s main outcomes. Mild adverse events, such as nasal and throat irritation, occurred in 50% of the treatment group against 24% on placebo, with no serious side effects reported. According to its information leaflet, Nasodren® can be used by adults and children aged 5 and over; it is not used during pregnancy or breastfeeding unless a doctor prescribes it. People allergic to plants of the Primulaceae family do not use it, and anyone taking anticoagulants, including acetylsalicylic acid (aspirin), or anticholinergic medicines consults a doctor first. Mucus discharge can last up to 2 hours after application, so driving is avoided during that period, and other nasal products are used 1.5 to 2 hours apart.
People who want a clinician’s view on their symptoms can book the free e-Health consultation at nasodren.com.
What Do People Ask About Maxillary Sinusitis?
Can maxillary sinusitis cause tooth pain?
Yes. The roots of the upper premolars and molars sit just below the maxillary sinus floor, so sinus pressure is felt as an ache across several upper back teeth. The pain usually increases when bending forward and eases as the sinusitis clears.
Can a tooth infection cause maxillary sinusitis?
Yes. An infected upper tooth, gum disease, an extraction opening or displaced implant material can infect the maxillary sinus. A 2023 meta-analysis of CT studies linked about 50% of maxillary sinusitis to a dental cause. Dental treatment of the source is usually required.
How long does maxillary sinusitis last?
Viral maxillary sinusitis usually improves within 7 to 10 days. Acute sinusitis lasts up to 4 weeks, subacute sinusitis 4 to 12 weeks and chronic sinusitis 12 weeks or longer.
Is maxillary sinusitis contagious?
The sinus inflammation itself is not contagious. The cold virus that often triggers it spreads from person to person, while dental and allergic maxillary sinusitis cannot be passed on.
Why does maxillary sinus pain get worse when I bend over?
Bending forward shifts fluid and raises pressure inside the blocked sinus. Because the maxillary ostium sits high on the sinus wall, mucus cannot drain by gravity and the pressure is felt in the cheek and upper teeth.
Does maxillary sinusitis always need antibiotics?
No. Most maxillary sinusitis is viral and antibiotics do not help it. Doctors consider antibiotics when symptoms last 10 days or more without improvement, worsen after improving, or are severe.
Key Takeaways: What Should You Know About Maxillary Sinusitis?
Maxillary sinusitis affects the largest sinuses, inside the cheekbones, and most cases are viral and self-limiting. Six points summarise the article.
- The maxillary sinus drains upward through an ostium high on its inner wall, so it relies on cilia rather than gravity.
- Cheek pain, blocked nose and aching upper teeth that worsen on bending forward are the hallmark symptoms.
- Sinus tooth pain affects several upper teeth; dental pain usually centres on one tooth and reacts to hot, cold or biting.
- About half of CT-confirmed cases had a dental cause in a 2023 meta-analysis, so one-sided symptoms or recent dental work call for a dental check.
- Antibiotics are reserved for suspected bacterial sinusitis, decided with a doctor.
- Eye swelling, vision changes, severe headache, confusion or neck stiffnessneed same-day emergency care.
This article is for informational purposes only and does not constitute medical advice. Consult a doctor, dentist or pharmacist before starting any treatment. Seek urgent care for eye swelling, vision changes, a severe headache, confusion or neck stiffness. Brand information for Nasodren® is included for commercial purposes; the medical content is sourced from published guidelines and peer-reviewed literature.
Which Medical Sources Support This Article?
- Rosenfeld RM, et al. Clinical practice guideline (update): adult sinusitis. Otolaryngology–Head and Neck Surgery. 2015;152(2 Suppl):S1-S39.
- Craig JR. Odontogenic sinusitis: a state-of-the-art review. World Journal of Otorhinolaryngology – Head and Neck Surgery. 2022;8:8-15.
- Vitali FC, Santos PS, Massignan C, Maia LC, Cardoso M, Teixeira CDS. Global prevalence of maxillary sinusitis of odontogenic origin and associated factors: a systematic review and meta-analysis. Journal of Endodontics. 2023;49(4):369-381.e11.
- Craig JR, et al. Diagnosing odontogenic sinusitis: an international multidisciplinary consensus statement. International Forum of Allergy & Rhinology. 2021.
- Anatomy, Head and Neck, Nose Paranasal Sinuses. StatPearls. NCBI Bookshelf.
- Zalmanovici Trestioreanu A, Barua A, Pertzov B. Cyclamen europaeum extract for acute sinusitis. Cochrane Database of Systematic Reviews. 2018;5:CD011341.
