A cavity that forms near the gum line can be successfully fixed using modern dental techniques and materials. These lesions, often called cervical caries or root surface caries, occur where the tooth meets the gum tissue. This area is structurally different from the rest of the tooth crown, making it highly vulnerable to decay and wear. Effective treatment depends on the severity of the damage, but professional restoration halts decay progression and restores the tooth’s structure.
Why Cavities Form Near the Gum Line
The area near the gum line is uniquely susceptible to damage because it involves a transition between different tooth structures. The main body of the tooth is covered by hard, protective enamel, but this layer thins significantly as it approaches the gum. Below the gum line, the tooth root is covered by a much softer, less mineralized layer called cementum.
Gum recession, which can occur due to age, periodontal disease, or aggressive brushing, exposes this softer cementum layer. Cementum decays much faster than enamel because it offers significantly less resistance to the acids produced by plaque bacteria. This exposure is a primary factor in the development of root surface caries.
Damage at the gum line is not always caused by bacterial decay, but can result from physical and chemical wear, known as non-carious lesions. Abrasion is often caused by harsh horizontal scrubbing with a hard-bristled toothbrush, which physically wears away the tooth structure. Erosion occurs when dietary acids from soft drinks, citrus fruits, or chronic acid reflux chemically dissolve the enamel and cementum.
Biomechanical stress from clenching or grinding the teeth, known as abfraction, can cause tiny V-shaped stress fractures at the gum line. These structural issues create niches for plaque accumulation, which initiates the decay process. Dry mouth (xerostomia) also increases risk because reduced saliva flow limits the mouth’s natural ability to neutralize acids and wash away bacteria.
Professional Treatment Options
Treatment for a gum line lesion depends on whether the damage is an active cavity or a non-carious lesion caused by abrasion or erosion. For decay, the dentist first removes the compromised tissue. The resulting defect is then filled with a restorative material, a process known as restoration or bonding.
Two primary materials are used for these restorations: composite resin and glass ionomer cement. Composite resin is a tooth-colored plastic and glass mixture that bonds directly to the tooth structure, offering excellent aesthetics and durability for visible areas. The bonding process involves etching the tooth surface with a mild acid, applying an adhesive agent, and then placing the resin, which is cured with a specialized light.
Glass ionomer cement (GIC) is frequently preferred for root surface lesions, particularly those extending below the gum line. GIC is a dental cement that chemically bonds to the tooth and slowly releases fluoride into the surrounding structure over time. This fluoride release helps prevent new decay from forming at the margins of the filling, which is beneficial in high-risk areas.
If the damage is a non-carious lesion, such as severe abrasion or abfraction, restoration may still be necessary to protect the underlying dentin and pulp from sensitivity and future decay. If gum recession is the primary underlying issue, causing sensitivity or decay risk, more complex intervention may be required. A gum graft may be considered to surgically cover the exposed root surface with new tissue, providing a biological barrier against further damage.
Long-Term Care and Prevention
Preventing the recurrence of gum line damage involves modifying the habits that led to the initial issue. A fundamental change is adopting a gentler, more effective brushing technique using a soft-bristled toothbrush. Instead of aggressive horizontal scrubbing, use small circular motions or the modified Bass method, angling the bristles at 45 degrees toward the gum line.
Controlling the chemical environment of the mouth is equally important to counter erosion. This involves reducing the frequency of consuming highly acidic foods and drinks, such as carbonated beverages, sports drinks, and citrus juices. When acidic items are consumed, rinsing the mouth with water afterward can help neutralize the acid before it can dissolve the tooth structure.
Addressing underlying medical and mechanical issues is also a significant preventive step. If nocturnal teeth grinding (bruxism) is contributing to abfraction lesions, a custom-fitted nightguard can protect the teeth from excessive stress. Individuals with chronic acid reflux (GERD) should consult a physician to manage the condition, as stomach acid can severely erode the tooth structure.
The consistent use of fluoride is a practical strategy for long-term maintenance, as it helps remineralize and strengthen the tooth surface. Daily brushing with fluoride toothpaste is recommended, and patients at higher risk may benefit from prescription-strength fluoride rinses or gels. Regular dental check-ups allow for professional application of high-concentration fluoride varnish and early detection of any new signs of wear or decay.