A gum bruise, medically termed a hematoma, is an accumulation of blood trapped beneath the surface tissue of the mouth. This common occurrence happens when small blood vessels within the delicate gum tissue rupture due to a localized impact or injury. The resulting discoloration is an internal bleed that does not break the skin’s surface, similar to a bruise on the arm or leg. While the appearance can be alarming, it is usually a temporary response to trauma.
Identifying Characteristics of Gum Bruising
Gum bruising visually presents as a distinct area of discoloration that stands out from the surrounding healthy pink tissue. Initially, the area may appear dark red or a deep, purplish-blue, reflecting fresh blood pooling beneath the mucosal surface. As the bruise resolves, the color typically shifts, sometimes becoming brownish-black or yellowish-brown as the body reabsorbs the trapped blood.
The affected area is localized, confined to a small patch where the trauma occurred. The bruise may feel slightly raised or swollen immediately following the injury, and it can be tender or sore. This localized patch is the hallmark of a gum hematoma, often found on the roof of the mouth or along the gumline near a tooth.
Primary Causes of Gum Bruising
The majority of gum bruises result from direct mechanical trauma that puts pressure on the soft tissue. Aggressive oral hygiene practices are frequent culprits, such as brushing with excessive force or overly vigorous flossing that snaps against the gums. Consuming sharp or hard foods, like crusty bread or certain chips, can accidentally scrape the gum lining, leading to a localized hematoma.
Dental procedures can also cause bruising, especially those involving injections or surgical manipulation of the gum tissue, such such as extractions or deep cleanings. Ill-fitting dental appliances, including dentures, retainers, or mouthguards, can rub or press against the gums, causing irritation that may result in bruising. Accidental injuries, like a fall or an impact to the mouth, provide enough blunt force to rupture the underlying capillaries.
Distinguishing Bruising from Other Gum Issues
It is important to differentiate a simple localized gum bruise from other systemic or chronic oral health problems. A hematoma is typically a temporary, trauma-induced injury that appears as a distinct, dark patch that fades and disappears within a week or two. In contrast, conditions like gingivitis and periodontitis present as generalized, persistent inflammation.
Gum disease causes diffuse redness and swelling across the gumline, often accompanied by bleeding when brushing or flossing, which signals chronic bacterial irritation. Discoloration that does not resolve and appears as multiple, tiny, pinpoint red or purple spots (petechiae or purpura) may indicate a systemic issue, such as a blood disorder or a side effect of certain medications. Other rare lesions, such as an amalgam tattoo, appear as a permanent bluish-grey mark and are localized pigmentation, not a bruise.
When to Consult a Dental Professional
While most gum bruises are minor injuries that resolve on their own, certain signs indicate the need for professional evaluation. You should consult a dentist if the discoloration or tenderness does not begin to fade within seven to ten days. Persistence beyond this typical healing period may suggest an underlying issue or a more serious injury.
Seek immediate attention if the bruise is accompanied by signs of infection, such as fever, persistent swelling, or spreading pain. If the bruising is extensive, interferes with your ability to eat or speak comfortably, or if the injury was caused by significant trauma, a dental assessment is warranted. An unexplained bruise, one that appears without any known cause, also requires consultation, as it may be a manifestation of a systemic health condition.