What are the Maxillary Sinuses?

Jacob Queen

The maxillary sinuses are cavities in the skull located behind the cheekbones, directly above the upper teeth. They are larger than the other paranasal sinuses and are more prone to infection. The actual evolutionary purpose of sinuses is unknown to science, but there are several theories. Some researchers believe sinuses work as sound chambers to make the voice louder, while others think they exist to reduce the weight of the skull; they may also help to humidify the air a person breathes, or even work as crumple zones to protect the brain from trauma in the event of an injury. Sinuses help the immune system function by facilitating the flow of mucus, but it is debatable whether they actually evolved for that purpose.

A saline nasal rinse can be used to relieve the symptoms of a maxillary sinus cyst.
A saline nasal rinse can be used to relieve the symptoms of a maxillary sinus cyst.

All sinuses are lined with a mucus membrane and covered with tiny hairs called cilia. The mucus collects foreign debris that a person breathes in and the cilia move back and forth, thereby helping to keep mucus flowing in the proper direction. This action helps to keep the airways clean and protect the body from disease.

The maxillary sinuses are located just above the upper teeth.
The maxillary sinuses are located just above the upper teeth.

In the maxillary sinuses, there are small openings called ostium that allow the mucus produced within the sinus to drain into the nose. If the cilia stop functioning properly, or if the openings become too small due to tissue inflammation, mucus is trapped in the sinus, and begins to attract bacteria. The result typically is a sinus infection.

A toothache might indicate a maxillary infection.
A toothache might indicate a maxillary infection.

One of the main reasons the maxillary sinuses are especially prone to infection is their close proximity to the teeth. Most sinus infections are caused by either head colds or allergies that linger, thereby resulting in backed up mucus. The maxillary sinuses are vulnerable to this as well, but they can also be infected due to dental inflammation, or even bacterial contamination directly from the teeth. If the teeth are the source of infection, dealing with dental issues can be an important part of the treatment.

Symptoms of maxillary infection include a feeling of pressure in the face, sharp pains in the cheeks, toothache, nasal congestion, fever, and fatigue. For mild sinus infections, most people rely on over-the-counter pain medication and decongestants. If the symptoms are more severe, doctors may prescribe antibiotic medications to kill the bacteria. Depending on the severity of the case, other treatments may also be used, including nasal sprays, nasal irrigation, steam therapy, prescription decongestants, and steroids. In extreme cases, surgery may be performed to enlarge the sinus openings to make it easier for the mucus to pass.

A maxillary sinus infection may be caused by a viral infection, allergy or tumor.
A maxillary sinus infection may be caused by a viral infection, allergy or tumor.

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Discussion Comments


How do you know if you have maxillary sinus drainage or if you just have a cold and runny nose?

I have noticed as I have gotten older that my nose runs a lot more than it used to. I am finding that I always make sure I have some Kleenex in my purse or my pocket.

This isn't usually associated with a sore throat, so I don't think it is from a cold. Since this is happening on a frequent basis, I am wondering if this is a sinus problem.

Sometimes I feel like there is some pain and pressure in my cheekbones and around my eyes. I have thought about using one of those nasal sprays to see if that would help or not.

My sister gets sinus infections a couple times a year, and she always gets an antibiotic and it clears up within a week or two. This makes me wonder if frequent sinus infections are hereditary?


@andee - I know how miserable sinus infections can be. I think the worst part about maxillary sinusitis is when all of your teeth ache.

It seems like I can find medications that will clear my sinuses, but have a hard time finding something that takes care of that aching feeling in my teeth. It is different than a toothache, and nothing seems to help.

I have found some relief from the nasal congestion using a neti-pot. This is a pot you fill with a saline solution and run through your nasal passages to help clear them.

I have found the more I can keep my nasal passages clear, the better I feel. You can find them at health food stores and some pharmacies carry them too.


Allergies are the major cause for my acute sinusitis. On dry, windy days when the pollen count is high, I just know I am going to be miserable all day.

I am one of those people who look forward to the first frost so I can get relief from my allergies and sinus infections.

I have maxillary sinus pressure around my eyes and on really bad days, all of my teeth ache as well. Many of the symptoms I have are similar to an upper respiratory tract infection. When my maxillary sinuses are involved, even my cheekbones will ache and throb.

My cough bothers me the most at night, and I have a constant sore throat because of my ongoing post nasal drip. I have a friend who has never had allergies or a sinus infection in her life.

She has cats and dogs in her house and keeps her windows open as often as she can. I don't have any pets, and never have my windows open even though I would like to. I can't imagine what life would be like without these sinus infections.


My mom has had recurring maxillary sinus infections for a long time. She is considering having surgery, but has heard this is a painful surgery, and not everyone she has talked to recommends it.

At this point, she tries to get by on medications, but she is miserable much of the time. She never knows what is going to bring one on.

Along with these sinus infections, she gets headaches and is just plain miserable. Her nose also runs all the time, and she can't go anywhere without making sure she has some tissue with her.


It's a good thing that the maxillary sinuses humidify the air we breathe. I know that in my area of the country, both summer and winter air can be extremely dry.

I wonder if taking in air that dry without a bodily area to act as a humidifier would hurt our lungs. I know that the body needs a lot of moisture, and I'm sure there must be more than one reason that our sinuses work to provide us with moist air.

I use a humidifier in my room during the winter, because the heater dries out the air and makes breathing through my nose difficult. I like knowing that I have my own internal humidifier at work during the rest of the year.


My aunt had something called a “deviated septum.” This meant that the bone separating her nostrils was not straight, and it caused endless sinus problems for her.

The paths between her mouth and her maxillary sinuses were also not normal. The whole design of her nose and sinuses made it hard for her to breathe through her nose. She kept getting infections and constantly had mucus dripping into her throat.

She had surgery to fix the abnormalities, and she told me that this is the best decision she has ever made. She can now breathe easier than she ever could, and she hasn't had a sinus infection since the surgery.


@kylee07drg – I suppose they can vary in severity, but I had a particularly bad maxillary sinus infection, and I had to get antibiotics to treat it. The worst part about it was the painful pressure I felt in my face.

It was almost like a toothache, but the pain was higher up. I had a little bit of trouble opening my mouth wide because of the sharp pains I was feeling throughout my cheeks and jaw area.

Also, I just felt physically drained. My nose was stuffy, and though I took decongestants, nothing helped. I eventually broke down and made an appointment with my doctor.

The infection had progressed to a pretty strong one by this time, so I had to have steroids as well to help my body fight it. The combination of steroids and antibiotics got me well in just a few days, whereas before, I thought I might never feel normal again.


I've had plenty of sinus infections, but I don't think I've ever experienced one involving the maxillary sinuses. My problems seem to be focused in my nasal sinuses, and sometimes, my ears get infected.

Though I am plenty miserable with this type of infection, it almost sounds like a maxillary one could be worse. I just have trouble breathing through my nose, but I don't experience tooth or jaw pain.

Has anyone here ever had a maxillary sinus infection? Is it as awful as it sounds? I hope I never find out firsthand, but I am curious, since I am prone to allergies and am at risk for all kinds of sinus infections.

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