Pain when biting, tapping, or applying pressure is a distinct, localized symptom signaling a problem with the tissues supporting the tooth. This discomfort, whether sudden during chewing or persistent tenderness, indicates inflammation or damage beneath the tooth’s surface. Although the sensation feels like it originates from the tooth, the pain results from pressure on the sensitive structures anchoring it in the jaw. This specific type of pain requires a professional dental evaluation to determine the exact cause and prevent the issue from worsening.
Why Pressure Causes Pain
The primary source of pain when pressure is applied is the Periodontal Ligament (PDL), a thin network of connective tissue fibers surrounding the tooth root. The PDL acts as a natural shock absorber, suspending the tooth within the jawbone and allowing minor movements during chewing. It is richly supplied with nerve endings and sensory receptors that detect pressure.
When the PDL becomes inflamed, a condition known as periodontitis, its ability to cushion forces is compromised. Pressure from biting or tapping compresses the inflamed tissue and triggers the nerve endings, resulting in sharp, localized pain. This inflammation can be caused by excessive mechanical force or by the spread of an infection from the tooth’s interior.
Primary Dental Causes
The most serious causes of pressure-induced pain originate from infection or structural failure within the tooth, irritating the ligament at the root tip.
Periapical Abscess
A Periapical Abscess is a collection of pus at the root end. It develops when deep decay or trauma kills the pulp tissue, allowing bacteria to travel out of the tooth’s apex. The immune response creates trapped fluid and pus, building pressure that pushes the tooth slightly out of its socket and compresses the Periodontal Ligament. This causes intense tenderness and often makes the tooth feel “high” in the bite, making it sensitive to contact.
Irreversible Pulpitis
Irreversible Pulpitis occurs when decay or a failing restoration reaches the nerve chamber, causing severe inflammation of the pulp. Although known for spontaneous pain from temperature changes, the inflammation can spread through the root tip to the surrounding PDL. Once the inflammation extends to the exterior support structures, the tooth becomes tender to pressure, signaling the infection is no longer confined to the pulp cavity.
Cracked Tooth Syndrome
Cracked Tooth Syndrome is a structural issue causing sharp, fleeting pain upon biting and often upon the immediate release of pressure. A hairline fracture extending into the dentin or pulp chamber allows the two segments of the tooth to flex independently under chewing force. This movement irritates the nerve and the PDL, leading to a quick, sharp pain that is difficult to localize. If the crack extends deep beneath the gum line, it can also cause localized inflammation in the supporting bone.
Referred Pain and Non-Structural Factors
Not all pressure sensitivity is caused by deep infection or structural fracture. Referred pain, where discomfort is felt away from the source, is common in the mouth and face.
Sinusitis
Inflammation or infection within the maxillary sinuses can cause a generalized, pressure-sensitive ache across the upper back teeth. The roots of the upper molars and premolars lie close to the floor of the maxillary sinuses. When sinusitis causes the sinus lining to swell and accumulate fluid, the pressure is transmitted directly onto the nerve endings of the nearby tooth roots. This referred pain can feel identical to a dental infection, making the upper teeth tender to pressure.
Bruxism
Excessive mechanical forces from habits like Bruxism (teeth grinding or clenching) can also lead to pressure sensitivity. The constant, intense pressure traumatizes the Periodontal Ligament, causing it to become inflamed and sore. This condition, sometimes described as a sprained tooth, makes the tooth feel bruised or tender when pressed, even without decay or infection.
Post-Operative Sensitivity
Post-operative sensitivity is a common transient cause, particularly after a deep filling or a new crown placement. If a restoration is slightly “high,” it hits the opposing tooth prematurely, placing excessive force on the tooth and causing PDL inflammation. This pain typically resolves quickly once the restoration is adjusted by a dentist.
Diagnosis and Treatment Pathways
Diagnosing the precise cause of pressure-sensitive tooth pain involves a comprehensive set of tests. A dental professional uses a selective Bite Test, often with a “Tooth Slooth” or cotton swab, applying pressure to individual cusps to pinpoint a crack. Sharp pain upon biting or releasing pressure helps confirm Cracked Tooth Syndrome.
An X-ray (periapical radiograph) checks the bone around the root tip for infection. A Periapical Radiolucency, appearing as a dark shadow, indicates bone loss from the body’s immune response. The dentist also uses a Cold Test to assess pulp vitality; a normal tooth responds briefly, while a tooth with irreversible pulpitis experiences heightened, lingering pain.
Treatment is based on the confirmed diagnosis.
- If the pulp is irreversibly infected or necrotic, the standard treatment is Root Canal Therapy, which removes the infected pulp tissue and seals the tooth interior.
- For a cracked tooth, a full coverage crown may be placed to hold the segments together and prevent flexing.
- If a crack extends too deeply, or if infection has caused extensive bone loss, extraction may be necessary.
- In cases of bruxism, a custom-fitted nightguard is prescribed to cushion forces and protect the PDL.