A sinus exposure is a complication that may occur after extraction of maxillary teeth with root tips that are in close proximity to the maxillary sinus.
This is an intra-operative complication that only occurs with teeth that have roots near the sinus. That means lower teeth and upper front teeth don't have the same procedural risk.
What is a sinus exposure?
A sinus exposure is a dental condition where the inner contents of the maxillary sinus becomes exposed to the oral environment. Essentially a new connection is formed between the sinus and mouth and it is called oro antral communication.
Under normal circumstances, your bone and your teeth serve as a buffer to prevent them from being in contact with one another.
The exposure can happen as a result of a complication from a tooth extraction. Most commonly it is due to extracting upper premolars or molars since they can be close to or right on top the sinus.
When the tooth gets extracted, it pulls the sinus out along with it causing a perforation or tear in the membrane. This is why another name for a sinus exposure is a sinus perforation.
The two pictures above are PA x-rays of the upper molars and premolars. For this particular patient you can see that the floor of the maxillary sinus is literally superimposed upon the root tips. Whenever you see this happen, it means that they are at a greater risk for sinus exposure during an extraction.
To offer you some contrast, the x-ray above shows a patient who have teeth that are far away from the sinus. As you can see there is quite a bit of distance separating the root tips and the floor of the sinus. For this patient, the risk for a sinus exposure is very low.
Signs & Symptoms
There are three ways to tell if you've a sinus exposure after an extraction.
Blow your nose. If your dentist suspects a sinus exposure, they'll pinch your nose and ask you to try to blow it. If you don't hear anything then you're safe. If you hear bubbling or hissing sounds then there may be a perforation.
Water in your nose. If you drink water and you feel water in your nose and sinus, it means that you've a perforation! If the membrane is intact, water shouldn't be able to get into your nose. The only way it can is if there is an exposure.
You can see it. Maybe not you but your dentist can certainly see it with their small intraoral mirror. What it looks like is similar to the lining of a balloon. If you can see that, it is the Schneiderian membrane, aka the floor of the maxillary sinus.
One time we had a patient come in for a consultation after she had an extraction done elsewhere. She stated that her tooth socket felt "weird".
Sure enough when I looked into the socket I saw the Schneiderian membrane. As she was breathing, I could see the membrane moving up and down. Luckily for her it wasn't perforated so it will heal all on its own.
Consequences of sinus perforation
You certainly don't want a perforated sinus because there are side effects.
Risk of infection. The sinus should not be communicating with the oral cavity. There are a lot of bacteria in the mouth which can get into the sinus and cause an infection.
Sinusitis. If you have an exposed sinus of course it will get inflamed. Roughly 50% of the patients develop sinusitis with 48 hours and 90% of the patients within 2 weeks.
Water going into nose. It is very inconvenient because whenever you drink water you'll have it going up your nose. That is certainly not fun. It also means that you probably can't go swimming either!
Food going into nose. Sounds gross but if water can get in there so can food.
Treatment for sinus exposure
Treatment for a sinus exposure will depend on how big the perforation is.
Less than 2 mm. No treatment is necessary, it will heal spontaneously on its own.
Greater than 2 mm. Lay a flap by peeling back the gums and then attempting to suture it together to close the hole. This can be done in conjunction with a bone graft, collagen plug, and a membrane.
Antibiotics will be prescribed. For sinus involvement you'll most likely be getting a potent antibiotic called amoxicillin with clavulanic acid (augmentin).
Nasal decongestant. Sudafed to help relieve sinus pressure.
Pain killers. To help alleviate any pain that may be present.
Avoid hard foods. Try to eat soft foods and drink fluids from the opposite side to avoid traumatizing the surgical site.
Avoid strenuous activity. Stay away from exercises which can increase sinus pressure.
Do not blow nose or sneeze with mouth closed. If you need to do either you MUST keep your mouth open. This prevents pressure build up in the sinus.
Do not touch area with tongue. There will be stitches over the surgical site, please do not play with it with your tongue.
Salt water rinse. Keep the area clean by rinsing with salt water.
No drinking through a straw. Sucking through a straw can create a lot of pressure in the mouth. We want to minimize intraoral pressure.
No smoking. Smoking can contaminate the surgical site and also cause a dry socket in addition to the sinus exposure. That would be a double whammy.
For a sinus exposure it may take 1-3 months for it to heal. For the smaller perforations, they typically spontaneously heal after one month. The larger exposures may take up to 3 months for it to heal. You'll need to be careful for awhile.
A sinus exposure is a common complication during the extraction of upper molars and premolars. The probability and risk of it occurring increases if the roots of the teeth are close to the sinus. Although the inverse is also true in that if the sinus is far away from the roots then the chances would be quite low.
Nonetheless, if it happens it happens there really isn't too much that you can do about it. There is no way for your dentist to prevent it from perforating because if the sinus is attached to the roots of your teeth, it will come out with it.
Your dentist can't circumvent the sinus during the extraction. Oftentimes they don't even know that it happened until after the tooth has come out. That is why it is one of the associated risks for the consent form that you probably signed for the procedure.