Pain in the back teeth during chewing is a common discomfort, ranging from a mild ache to a sharp, intense pain. It often signals an underlying issue requiring attention. Understanding the various reasons behind this specific dental pain is the first step toward seeking appropriate care.
Common Dental Causes
Tooth decay, or a cavity, often causes pain when pressure is applied during chewing. Bacteria produce acids that erode the tooth’s hard outer enamel. As decay progresses into the softer dentin layer, which contains microscopic tubules leading to the tooth’s nerve, chewing forces can stimulate these nerve endings. Deeper cavities allow for more direct transmission of pressure and temperature changes to the sensitive inner tooth.
A cracked tooth can also cause sharp pain when biting down or releasing pressure. These hairline fractures are often microscopic and may not be visible on X-rays, making diagnosis challenging. When biting, the crack can flex slightly, irritating the pulp, the tooth’s inner tissue containing nerves and blood vessels. Releasing the bite can cause a sudden, brief pain as the crack closes.
Old or failing dental fillings can cause chewing pain. Over time, fillings can wear down, chip, or develop small gaps at their edges. These imperfections expose the sensitive underlying tooth structure to food particles, bacteria, or temperature fluctuations. Direct pressure on a compromised filling or exposed tooth area during chewing can lead to discomfort. A loose filling might also shift slightly under chewing force, causing pain.
Inflammation of the dental pulp, known as pulpitis, often results from deep decay, repeated dental procedures, or trauma. The pulp is enclosed within the rigid tooth structure; when inflamed, swelling increases pressure on the nerves. Chewing forces further compress this inflamed tissue within the confined space, intensifying the pain. This condition can be reversible if caught early, or irreversible, potentially requiring root canal treatment.
Gum and Jaw-Related Issues
Gum disease, including gingivitis and periodontitis, can cause pain and sensitivity in the teeth during chewing. Gingivitis involves inflammation of the gums, which can become tender and bleed easily. If untreated, it can advance to periodontitis, where the infection spreads to the supporting bone and ligaments around the teeth. Chewing puts pressure on these inflamed or compromised tissues, causing discomfort.
Disorders of the temporomandibular joint (TMJ) can cause pain that radiates to the back teeth, especially when chewing. The TMJ connects the lower jaw to the skull, enabling movements like biting and speaking. Problems with the joint or surrounding muscles can lead to referred pain, felt in an area other than its true source. Chewing can strain the TMJ and its associated muscles, leading to discomfort perceived in the molar region.
Bruxism, the involuntary grinding or clenching of teeth, particularly during sleep, exerts excessive stress on the back teeth. This chronic force can cause micro-traumas to the tooth structure, leading to enamel wear, increased sensitivity, and hairline cracks. Constant muscle tension from bruxism can also result in soreness in the jaw muscles, radiating to the teeth and making them tender and painful when chewing. Sustained pressure can also inflame the ligaments supporting the teeth.
Other Potential Sources of Pain
Sinus infections can sometimes cause pain in the upper back teeth, mimicking a dental issue. The maxillary sinuses are air-filled cavities located directly above the roots of the upper molars. When inflamed or infected, pressure buildup within them can mimic a toothache. Activities like chewing or bending over can exacerbate this pressure, leading to discomfort in the upper back teeth due to their close anatomical proximity.
An impacted wisdom tooth, a third molar that does not fully erupt through the gum line, can cause pressure or pain in adjacent back teeth. If partially or completely trapped within the jawbone, it can press against the roots of the neighboring second molar. This pressure can intensify when chewing, leading to discomfort or a dull ache. Gum tissue around a partially erupted wisdom tooth can become inflamed, a condition known as pericoronitis, which also contributes to chewing pain.
When to Seek Professional Help and What to Expect
Persistent pain in the back teeth when chewing requires a professional dental evaluation. Ignoring the pain or attempting self-treatment can worsen underlying conditions, potentially resulting in more complex dental procedures. A dentist can pinpoint the exact cause of discomfort and recommend the appropriate course of action.
Certain signs indicate an urgent need for a dental visit. These include severe, throbbing pain that interferes with daily activities or sleep, noticeable swelling in the face or gums, a fever, or pus discharge around the tooth. Difficulty opening the mouth fully or pain when swallowing also suggests a serious infection or other complications and should prompt immediate professional attention.
During a dental visit, you can expect a thorough examination. The dentist will likely perform a visual inspection of your teeth and gums, looking for decay, cracks, or signs of gum disease. Dental X-rays are commonly taken to reveal issues not visible to the naked eye, such as deep cavities, bone loss, or problems with impacted teeth. The dentist may also use a bite test to identify a cracked tooth or assess dental pulp health.
While awaiting your dental appointment, you can take some temporary measures. Consuming soft foods can reduce pressure on the affected tooth during chewing. Over-the-counter pain relievers, such as ibuprofen or acetaminophen, can alleviate pain temporarily. Rinsing your mouth gently with warm salt water several times a day can also provide relief for inflamed or tender gums.