A dental crown is a custom-made cap placed over a damaged or weakened tooth, restoring its shape, size, and strength. This restoration covers the entire visible portion of the tooth down to the gum line. Bleeding around the crown while brushing signals irritation or inflammation in the adjacent gum tissue. Understanding this localized reaction is key to resolving the issue and protecting the long-term health of the crowned tooth.
Understanding Gum Inflammation Around Dental Crowns
The most frequent reason for bleeding gums around a dental crown is gingivitis, the earliest stage of gum disease. This inflammation is caused by the accumulation of bacterial plaque, a sticky film that constantly forms on the tooth surface. Plaque naturally gathers where the crown meets the tooth and the gum tissue.
If plaque is not removed consistently, bacteria release toxins that irritate the gum tissue. This triggers an immune response, causing the gums to become red, swollen, and prone to bleeding upon physical disturbance, such as brushing or flossing. The gum tissue around a crown is particularly susceptible because the margin, or edge, of the restoration creates a slight ledge where bacteria can settle.
Even a microscopic amount of plaque accumulation at the crown-gum interface can provoke this inflammatory reaction. The bleeding serves as a direct sign that the delicate gum tissue is compromised by bacterial irritants. This localized irritation becomes chronic if the plaque is not regularly cleared from the area.
Structural Problems Related to the Crown Margin
While plaque accumulation is the primary biological cause, the crown itself can contribute if its fit is less than ideal. The crown margin, the border where the restoration ends and the natural tooth structure begins, must be precisely flush with the tooth. An ill-fitting margin leaves a microscopic gap that is impossible to clean effectively, creating a persistent bacterial reservoir.
Another common structural issue is a crown overhang, where the restoration material extends beyond the natural contour of the tooth and sits against the gum tissue. This excess material acts as a permanent physical irritant, constantly pushing on the gum tissue and preventing proper healing. Overhangs also trap food debris and plaque, exacerbating inflammation.
Improper contouring, where the crown is shaped too bulbously or too flatly, can make effective flossing difficult. This poor shape prevents the gum tissue from sitting snugly against the crown, promoting plaque retention. Furthermore, placing the crown too far beneath the gumline, known as “violation of the biologic width,” can trigger a chronic inflammatory reaction as the body attempts to push the foreign material away.
Residual dental cement that was not fully cleared during placement can harden beneath the gumline. This rough material attracts plaque and mechanically irritates the gum tissue, leading to persistent bleeding. In rare instances, an allergic reaction to certain crown materials, particularly metal alloys, can also cause localized gum redness and swelling.
Immediate Steps and Improved Oral Hygiene
If you notice bleeding around your crown, the first step is to intensify at-home cleaning efforts in that specific area. Do not stop brushing the area, as this allows bacterial plaque to accumulate and worsen inflammation. Instead, focus on mechanical removal of the irritant.
Use a soft-bristled toothbrush and apply gentle, thorough circular motions, angling the bristles toward the gumline where the crown meets the tissue. This technique helps disrupt the bacterial film without causing trauma to the already inflamed gums. Brushing twice daily for two minutes remains the foundational step for maintaining gum health.
Flossing around the crowned tooth is necessary, and specialized tools can make this easier. Floss threaders help guide traditional floss under the crown’s contact point, or a water flosser can direct a stream of water beneath the gumline to flush out trapped debris and bacteria. Use a gentle “C-shape” motion with the floss to clean the entire circumference of the tooth.
Rinsing with warm salt water or a non-alcohol antiseptic mouthwash can help manage inflammation and temporarily reduce the bacterial load. A simple saline rinse involves dissolving half a teaspoon of salt in eight ounces of warm water. These rinses should be used after brushing to soothe irritated tissue and promote a cleaner healing environment.
When to See the Dentist for Bleeding
While improved home care can resolve bleeding caused by simple plaque-induced gingivitis within a week, persistent bleeding indicates a more deeply rooted problem requiring professional attention. Schedule a dental appointment if the bleeding continues despite rigorous oral hygiene for more than seven days.
Signs like pain, swelling, the presence of pus, or noticeable loosening of the crown are urgent indicators that the underlying issue is severe. The dentist will perform a thorough examination, including periodontal probing to measure the depth of the gum pocket around the crown. X-rays will also likely be taken to check for issues invisible to the naked eye.
X-rays can reveal structural problems such as crown overhangs, residual cement, or decay forming under the crown. The dentist may perform a professional cleaning, known as scaling, to remove hardened plaque and tartar from the crown margin and root surface. If the issue is a structural defect, such as a large overhang or a margin violation, the crown may need to be adjusted, reshaped, or entirely replaced to ensure a proper, non-irritating fit.