What is a Sinus Infection (Sinusitis)? A sinus infection can create pressure and pain in the mouth and cause a sinus tooth pain. Specifically, this is due to pressure and pain in the maxillary sinuses located behind the cheek bones. Sinus tooth pain is often confused with other causes of tooth pain, including gum disease , tooth decay , or an impacted wisdom tooth . What Causes Sinus Infections? A sinus infection occurs when bacteria from the nose enter the sinuses. To help you assess whether you have a sinus tooth pain or a toothache caused by something else, take note of symptoms that occur in addition to pain around the upper teeth, eyes, or cheekbones. Sinus Infection Symptoms Any type of sinusitis, including maxillary sinusitis, can be chronic or acute.  Symptoms of acute maxillary sinusitis include: Fever Stuffy nose and nasal discharge Bad breath Pain that is worse when sitting up than when lying down Tenderness, redness, or swelling in the cheekbones ...