The experience of a tooth hurting when pressure is applied, such as during chewing or biting down, signals that an underlying structure is compromised. This discomfort indicates an issue with the tooth, its supporting tissues, or a nearby joint. The pain can manifest as a sharp shock or a dull, lingering ache, with the sensation often pointing directly to the cause. Understanding the source is the first step toward finding relief and preventing a small issue from becoming a dental emergency.
Causes Stemming from Structural Damage
Discomfort that arises sharply when biting down is often linked to a breakdown in the physical integrity of the tooth’s protective layers. Dental caries, commonly known as cavities, can erode the outer enamel and dentin, leaving the underlying, more sensitive structures exposed to the forces of chewing. When pressure is applied directly over the decayed area, it irritates the pulp chamber, causing a focused and immediate spike of pain.
Cracked Tooth Syndrome, involving hairline fractures often invisible to the naked eye, is another frequent culprit. When biting, the cracked segments momentarily flex and separate, causing fluid movement within the dentinal tubules. This movement stimulates the nerve fibers, resulting in a sudden, sharp pain often felt most intensely just as the biting pressure is released.
Older or failing restorations, such as a loose or leaky filling, also create structural vulnerability. A filling that sits too high bears excessive force, causing trauma to the ligament holding the tooth in the jawbone. Furthermore, a breakdown in the seal allows bacteria and pressure to penetrate the tooth’s interior, leading to sensitivity and pain when the restoration shifts during chewing.
Pain from Internal Nerve Inflammation
When pain is not just a brief, sharp reaction to biting but a deep, throbbing ache that can linger, it often signals inflammation within the dental pulp, the soft tissue containing the tooth’s nerves and blood vessels. This condition is called pulpitis, and it occurs when decay or trauma allows bacteria to invade the pulp chamber. The inflammation causes the tissue to swell, but because the pulp is encased in the hard, unyielding dentin, this swelling leads to a rapid increase in internal pressure.
In cases of reversible pulpitis, the inflammation is mild, and the pain, though present when chewing or exposed to cold, subsides quickly once the stimulus is removed. However, if the bacterial invasion is extensive, irreversible pulpitis develops, leading to severe, spontaneous pain that can last for minutes or hours without any trigger. This intense, lingering pain is a sign that the pulp tissue is dying and can no longer recover.
The progression of irreversible pulpitis can result in a dental abscess, a pocket of pus that forms at the tip of the tooth root. This infection causes a localized swelling in the bone beneath the tooth, which makes the tooth feel extruded or “high” in the bite. Chewing directly compresses the infected tissue against the bone, resulting in a persistent, severe throbbing pain that is aggravated by any contact.
Pain Related to Surrounding Tissues and Jaw
Not all chewing pain originates from the tooth structure, as discomfort can arise from supporting structures or adjacent areas. Periodontal disease, an infection of the gums and bone, is a common cause often mistaken for a tooth problem. As the disease advances, it destroys the bone anchoring the tooth, causing the tooth to become mobile or tender. Chewing places force on this compromised support system, leading to a generalized ache or soreness.
Referred pain from the maxillary sinuses can also mimic a toothache, typically affecting the upper molars. The roots of these upper back teeth are positioned very close to the floor of the maxillary sinus cavity. When a sinus infection (sinusitis) causes the sinus lining to swell and fill with fluid, the resulting pressure pushes down on the nerve endings near the tooth roots. This pressure is interpreted by the brain as tooth pain, often worsening when the head is moved suddenly or bent forward.
Issues with the jaw joint, known as Temporomandibular Joint (TMJ) dysfunction, can also cause pain that radiates into the teeth. The TMJ acts as a sliding hinge connecting the jawbone to the skull, and inflammation or muscle tension in this area can trigger facial pain that the brain misinterprets as a dental issue. This referred pain is usually a dull, aching sensation that affects multiple teeth and is directly linked to the movement of the jaw, such as when opening wide or chewing tough food.
Immediate Steps and Professional Assessment
While waiting for a dental appointment, several simple measures can help manage the immediate discomfort of chewing pain. These measures are temporary and do not solve the underlying issue causing the sensitivity.
Immediate Relief Measures
- Take over-the-counter nonsteroidal anti-inflammatory drugs (NSAIDs), such as ibuprofen, to reduce pain and local inflammation.
- Avoid chewing on the painful side and limit the diet to soft foods to minimize mechanical irritation.
- Rinse the mouth gently with warm salt water to soothe inflamed gum tissue and keep the area clean.
- Apply a cold compress to the outside of the cheek for 15 to 20 minutes at a time to numb the area and reduce any swelling.
A professional assessment is mandatory, especially if the pain lasts longer than a day or two, or if it is severe and spontaneous. Immediate dental attention is required if the pain is accompanied by facial swelling, a fever, or difficulty swallowing or breathing. These symptoms indicate a rapidly spreading infection, such as an abscess, which needs prompt medical intervention.