If you have ever felt a throbbing ache in your teeth while battling a cold, the flu, or a sinus infection, you are not alone. This common experience is a side effect of a respiratory illness; the discomfort seems to originate in your mouth but is caused by the infection elsewhere in the body. This tooth pain is generally temporary, not an indication of a new dental problem. Understanding the anatomical relationships within your head and the body’s response to infection explains why your teeth feel sensitive when you are sick.
Understanding Referred Pain from Sinus Congestion
The most frequent cause of tooth pain during an upper respiratory infection is referred pain originating in the sinuses. Your skull contains air-filled spaces called paranasal sinuses; the pair most relevant to tooth pain are the maxillary sinuses. These large cavities are positioned directly above the upper back teeth, specifically the molars and premolars.
When you have a cold, flu, or sinusitis, the lining of the maxillary sinuses becomes inflamed and swollen. This causes a buildup of fluid and mucus, increasing the internal pressure within the sinus cavity. Since the roots of your upper teeth are located close to the floor of the swollen sinus, this pressure begins to press down on the sensitive nerve endings supplying those teeth.
The brain receives pain signals from these compressed nerves but interprets the message as originating from the teeth themselves. This referred discomfort presents as a dull, generalized ache across several upper teeth. This pain often intensifies when you bend over, lie down, or move your head suddenly, as these actions shift the fluid and pressure within the sinus cavity. Once the sinus infection clears and the inflammation subsides, the pressure releases, and the tooth discomfort disappears.
How Systemic Illness Affects Oral Health and Sensitivity
Beyond sinus pressure, the body’s response to fighting an illness can increase oral sensitivity and discomfort. A common side effect of many illnesses, coupled with medications, is dehydration and dry mouth, medically known as xerostomia. Saliva plays a significant role in oral health by neutralizing acids and washing away bacteria, acting as a protective buffer for the teeth.
When saliva flow is reduced, this protective layer is diminished, making the teeth more vulnerable to sensitivity and pain. Many respiratory infections trigger a systemic inflammatory response as the immune system works to clear the pathogen. This widespread inflammation can exacerbate minor, pre-existing dental issues, such as a small cavity or mild gum recession.
The inflammation makes the nerves in and around the teeth more reactive, turning a previously unnoticed issue into a source of throbbing pain. If an illness includes gastric distress, such as vomiting, the teeth are temporarily exposed to stomach acid. This acid exposure can erode the enamel layer, leading to temporary but sharp sensitivity, especially to temperature changes, until the mouth’s pH levels return to normal.
Differentiating Sickness Pain From Dental Emergencies
While most tooth discomfort during an illness is temporary and resolves with the sickness, it is important to know the difference between referred pain and a true dental issue. Sinus-related pain is a dull ache affecting multiple upper teeth and is accompanied by respiratory symptoms like congestion or facial pressure. If the pain is localized to a single tooth, especially a lower tooth, or presents as a sharp, jabbing pain, it is less likely to be sinus-related.
A true dental emergency is often indicated by specific, intense symptoms that demand professional attention. Pain that occurs sharply when you bite down, or sensitivity to hot or cold that lingers for more than 30 seconds, suggests a deeper issue like a fracture or nerve damage. Swelling in the gum tissue, face, or jaw focused around one tooth, or a fever that is disproportionately high for your cold symptoms, may indicate a dental abscess.
If your tooth pain persists long after your respiratory symptoms have cleared, or if it meets the criteria for sharp, localized pain, you should consult a dentist immediately. For temporary, illness-related aches, focusing on managing congestion with steam inhalation and staying hydrated can bring relief by reducing the pressure on the nerve roots. Any discomfort that is severe or accompanied by focused swelling should be professionally evaluated to prevent potential complications.