Gums, the soft tissues in your mouth, can bruise just like the skin on the rest of your body. Gum tissue is delicate and highly vascular, meaning it contains many small blood vessels. Trauma to the gums can cause these vessels to rupture, leading to localized bleeding beneath the surface. This results in a visible discoloration, which is commonly known as a bruise.
The Science Behind Gum Bruising
A bruise, medically termed a contusion, occurs when physical impact damages capillaries, the tiny blood vessels located just beneath the tissue surface. When these capillaries rupture, blood leaks out and pools in the surrounding connective tissues, forming a hematoma. This pooled blood causes the characteristic dark discoloration.
Gum tissue (gingiva) is soft, thin, and richly supplied with blood vessels. When trauma occurs, the resulting hematoma is often immediately visible as a purplish, dark red, or even black spot against the normal pink tissue. The body eventually reabsorbs the trapped blood over time, which causes the bruise to fade naturally.
Primary Sources of Oral Trauma
Gums often get bruised through mechanical injury during daily oral hygiene. Aggressive brushing, especially with hard-bristled toothbrushes or excessive force, can easily scrape and damage the delicate gum line. Improper or overly vigorous flossing techniques can also cause small cuts or blunt trauma to the interdental papillae, leading to bruising.
Bruising frequently occurs following necessary dental procedures that involve manipulation of the gum tissue. Scaling and root planing, tooth extractions, or routine deep cleanings can cause temporary trauma and discoloration. Ill-fitting dental appliances, such as new dentures, retainers, or mouthguards, can also exert chronic pressure or rub against the gums, resulting in localized injury.
Accidental trauma from everyday activities is another source of gum bruising. This can involve biting down forcefully on hard foods like nuts, crusty bread, or chips, causing a sharp edge to injure the gum. Sudden impacts to the mouth, such as from a fall or a sports injury, can also cause contusions to the oral soft tissues.
Other Causes of Discoloration
While not true bruises, other irritations can mimic the discoloration of a contusion. Consuming extremely hot foods or liquids can cause thermal burns to the gingiva, which may appear red and sometimes blistered. Exposure to strong chemical irritants can also cause tissue damage and discoloration.
Identifying True Gum Bruising
A true gum bruise presents as a distinct, localized area of discoloration, ranging from dark red to purple or black, depending on the severity and age of the injury. The site of the injury may also exhibit mild, localized swelling and tenderness to the touch. This discoloration is often slightly raised and is directly preceded by a known traumatic event.
It is important to distinguish a simple bruise from other oral lesions that also cause discoloration. Conditions like severe gingivitis or periodontitis cause a generalized redness and inflammation, not a distinct, dark spot. Oral lesions like canker sores, abscesses, or oral malignancies often present with white, gray, or ulcerated surfaces, or with chronic, unexplained growth. A key differentiator for a bruise is its clear association with recent trauma and its tendency to be localized due to the underlying blood collection.
Self-Care and Dental Consultation
For minor gum bruising, self-care measures can help manage discomfort and promote healing. Rinsing the mouth gently with a warm saltwater solution (about one teaspoon of salt in one cup of water) can help keep the area clean and reduce inflammation. Applying a cold compress to the cheek over the bruised area can minimize swelling and provide temporary pain relief.
It is advisable to eat a soft diet for a few days and avoid brushing or flossing directly on the injured tissue until the initial tenderness subsides. Most simple gum bruises are self-limiting and will fade and heal completely within three to five days. If the bruise does not show signs of improvement within a week, or if it worsens, professional evaluation is necessary.
Consulting a dentist is important if the bruise is accompanied by severe, unmanageable pain or persistent bleeding. Other concerning signs include rapid growth of the discolored area, the presence of pus, or a fever, which may indicate an infection or a more serious underlying issue. If a bruise appears without any clear cause or if it recurs frequently, professional assessment is needed.