A sinus infection, or sinusitis, occurs when viruses or bacteria infect the sinus linings. The results can be uncomfortable symptoms, including facial pain and pressure, runny nose, headache, and, sometimes, tooth pain.

Sinuses are cavities that are filled with air. Small hairs called cilia line the sinuses. Cilia hairs help move air, mucus, and bacteria or viruses through for filtration.

The sinuses allow a route for air to flow and warm the air that enters through the nose.

Without the sinuses, a person’s head would be heavier. The sinuses also help determine the sound of a person’s voice, as their voice resonates or changes with air vibrations in the sinuses.

A sinus infection can cause dental pain. According to an older article in the British Dental Journal, the most common sinus infection site that causes dental pain is the maxillary sinus.

The sinuses, teeth, and gums all share similar nerves that can transmit pain signals.

Inflammation due to sinus infection or dental disease can press on these nerves, leading to pain. A person may interpret these signals as dental pain.