We see it pretty frequently in our office. A patient will come in with pain and pressure in the upper back molars, with no positive response to our diagnostic tests - no dental reason whatsoever for this problem. When that happens, our minds jump to one likely culprit - the sinuses.
It may sound odd, but the relationship actually makes perfect sense. Like fingerprints, everyone's sinuses- mucous-lined, air-filled spaces in the skull - are a bit different, but there are overarching similarities. You likely have four sets of paranasal sinuses:
The maxillary sinuses sit right above the upper teeth. As the expand due to inflammation, they have nowhere to go but down, pressing up against the roots of your teerth and causing the pressure and pain that might lead you to the dentist. This will often be diffuse pain, hard to localize to one tooth. In fact, if you are missing teeth, sinuses will often continue to pneumatize (their natural process of expansion during development) into the vacancy. When this happens it becomes necessary to surgically lift the sinus to make room for dental implants.
The resulting tooth ache won't be your only hint that you've got sinusitis. Congestion, headaches, swelling, mucus discharge and fever are all potential symptoms. Home remedies such as applying moist heat to the face, keeping a humidifer running, taking decongestants and using saltwater nasal washes can all help. In many cases however, especially when dealing with a bacterial infection, you may need to see your doctor and take a course of antibiotics or other medication.
No question, when you've got a toothache, go see your dentist. But in the absence of a diagnosed problem with your teeth, consider visiting your ENT - this pain may be a sinus issue!