A swollen inner cheek can be an uncomfortable symptom. While many instances are temporary and benign, understanding the various reasons is important for self-care or seeking professional guidance. This symptom can stem from simple mechanical irritation to more complex issues within the oral cavity or broader systemic health conditions.
Common Mechanical and Irritation Causes
Accidental biting of the inner cheek is a frequent cause of localized swelling, often occurring during eating or talking. This trauma can lead to pain, discomfort, and inflammation, sometimes predisposing the area to further accidental bites as it swells.
Dental appliances, like braces or ill-fitting dentures, can cause irritation and subsequent swelling of the inner cheek lining. Constant rubbing or pressure from these devices can create friction, leading to inflamed tissue. Minor burns from hot foods or liquids are another common irritant, resulting in redness, swelling, and discomfort. These superficial burns typically heal within about a week.
Canker sores (aphthous ulcers) frequently appear on the inner cheeks and lips, contributing to localized swelling and pain. These small, white or yellow oval-shaped ulcers with a red border can develop following minor mouth injuries, stress, or food sensitivities. While painful, most canker sores are not contagious and typically resolve on their own within one to three weeks.
Infections and Inflammation Within the Mouth
Oral infections are a common cause of inner cheek swelling, often requiring dental or medical intervention. A dental abscess, an infection at the root of a tooth, can lead to significant swelling in the surrounding gum and cheek area. This occurs when bacteria enter the tooth’s pulp, forming a pocket of pus that expands into adjacent tissues.
Impacted wisdom teeth are a frequent source of inflammation and swelling in the back of the mouth, potentially extending to the inner cheek. When these teeth are unable to fully erupt, they can cut into the cheek or create an environment where bacteria thrive, leading to pain, swelling, and sometimes infection. Pericoronitis, an inflammation of the gum tissue around a partially impacted wisdom tooth, can also cause facial swelling.
Gum disease, including gingivitis (inflammation of the gums) and periodontitis, can contribute to localized swelling that may involve the inner cheek. This inflammatory response stems from bacterial plaque buildup along the gumline, leading to redness, tenderness, and swelling of the gum tissue.
Salivary gland issues, such as a blocked salivary duct or an infection called sialadenitis, can cause pronounced inner cheek swelling. The major salivary glands, including the parotid glands, can become inflamed and painful if their ducts are obstructed or infected. Symptoms of sialadenitis may include tenderness, a foul taste in the mouth, fever, and swelling.
Oral infections like thrush, caused by Candida albicans, typically present as creamy white patches inside the mouth, including the inner cheeks. Thrush can lead to soreness, redness, and puffiness, contributing to oral irritation. This fungal infection is more common in individuals with weakened immune systems or those taking certain medications.
Systemic Conditions and Other Factors
Less common but more serious causes of inner cheek swelling involve systemic conditions or other factors. Allergic reactions can manifest as angioedema, a condition causing sudden and significant swelling around the eyes, lips, or cheeks. This reaction occurs when the immune system overreacts to certain foods, medications, or environmental allergens.
Viral infections, such as mumps, cause swelling of the salivary glands, notably the parotid glands in the cheek and jaw area. While less common now due to widespread vaccination, mumps can still lead to pronounced cheek enlargement. Certain medications can also have side effects that include facial or oral swelling.
Rarely, inner cheek swelling may indicate the presence of growths. Benign growths like fibromas or lipomas can form in the soft tissues of the cheek, leading to a noticeable lump. More rarely, malignant conditions such as buccal mucosa cancer, which affects the inner lining of the cheek, can present as a lump, white or red patches, or jaw swelling. Although uncommon, persistent or concerning symptoms warrant professional evaluation.
Autoimmune conditions, where the body’s immune system attacks its own tissues, can affect oral health and potentially contribute to inner cheek inflammation. Conditions like Sjögren’s syndrome can reduce saliva production, leading to dry mouth and increased susceptibility to oral issues. Other autoimmune diseases, such as lupus or oral lichen planus, can cause ulcers, sores, or inflammatory lesions on the oral mucous membranes, which may involve the inner cheek and cause discomfort or swelling.
When Professional Help is Needed
While many instances of inner cheek swelling resolve on their own, certain signs indicate the need for professional evaluation. Persistent swelling that does not improve or worsens over a few days warrants attention, especially if accompanied by severe pain, as this can suggest a more serious underlying issue.
Warning signs include fever or chills, indicating an infection that may require antibiotics. Difficulty breathing, swallowing, or opening the mouth wide necessitate immediate medical assessment. Redness, warmth, or pus discharge from the swollen area also points to an infection requiring professional care. Recurrent swelling, or swelling after injury or trauma, should also be evaluated to ensure proper healing and address complications.