Finding an unexpected lump inside the cheek, or buccal mucosa, can be alarming. The oral mucosa is the protective lining of the mouth, and its delicate nature makes it susceptible to various issues. While a bump causes immediate concern, the overwhelming majority of these growths are temporary, benign, and easily explained by common irritations. Understanding the potential origins of these lesions helps distinguish between a minor inconvenience and a condition requiring professional evaluation.
Benign Bumps from Injury and Inflammation
The most frequent source of a cheek bump involves a localized reaction to physical trauma. Constant friction from sharp tooth edges, ill-fitting dental appliances, or repeatedly biting the inner cheek can injure the tissue. This chronic irritation leads to a protective buildup of fibrous tissue as the body attempts repair.
This process often results in a traumatic fibroma, which is a scar-like reaction. A fibroma appears as a smooth, firm, dome-shaped growth, typically the same color as the surrounding cheek lining. These lesions are generally painless, slow-growing, and usually reach a maximum size of about one centimeter. They represent a healed end-product of a prolonged inflammatory response and carry no risk of becoming cancerous.
Another common source of a palpable lump is the initial swelling phase of an aphthous ulcer, commonly known as a canker sore. These lesions often begin with a tingling or burning sensation, followed by localized inflammatory swelling beneath the surface. The swelling eventually breaks down to form the characteristic shallow ulcer, which features a white or yellowish center encircled by a distinct red border.
These sores are not contagious and usually resolve on their own within one to two weeks. Less frequently, inflammation from an infection at the root of a nearby tooth can cause localized swelling in the cheek tissue adjacent to the gumline. This swelling represents the body’s immune response containing the infection and may feel like a firm, painful bump.
Cysts and Salivary Gland Related Causes
A different category of bumps involves issues related to the minor salivary glands, which are numerous small glands distributed throughout the cheek lining. The most frequent cause in this group is the mucocele, which arises when a minor salivary gland duct becomes obstructed or damaged, often by trauma such as biting. When the duct ruptures, saliva leaks into the surrounding connective tissue, causing a fluid-filled lesion to form.
Mucoceles typically present as soft, dome-shaped, mobile swellings ranging from a few millimeters up to two centimeters in diameter. They often have a translucent or bluish hue due to mucus accumulation just beneath the surface. A defining characteristic is their tendency to spontaneously rupture, temporarily flattening as the fluid drains, only to reform if the underlying duct damage persists.
A ranula is a specific, larger type of mucocele that develops on the floor of the mouth, often involving the major sublingual salivary gland. While rare on the cheek itself, it is an example of salivary gland-related fluid accumulation. These can grow large enough to interfere with swallowing and speech, necessitating professional intervention.
Sometimes, a hard bump is caused by sialolithiasis, or the formation of a salivary stone, though this is rare in the minor glands of the cheek. These stones are calcified deposits that block the flow of saliva through the duct, causing the gland to swell and become painful. Pain and swelling from sialolithiasis often intensify during mealtimes as the body increases saliva production, pressing against the blockage.
When to Consult a Healthcare Professional
While most cheek bumps are benign and self-limiting, certain signs should prompt a visit to a dentist or physician. The most important indicator is the duration of the lesion, as any bump or sore that persists for longer than two to three weeks should be examined. This persistence suggests the body is unable to resolve the issue on its own.
A professional consultation is also warranted if the bump exhibits rapid growth or sudden changes in texture or color. Concerning warning signs include:
- Unexplained numbness in the area
- Difficulty swallowing or moving the jaw
- Any spontaneous, unprovoked bleeding
- Lesions that feel unusually firm, are fixed to deeper tissues, or lack mobility
If the bump fails to shrink or disappear after the suspected source of irritation, such as a sharp tooth, has been removed or smoothed, a healthcare professional should conduct a thorough assessment.