Gingival recession is the apical migration of the gum tissue margin, resulting in the exposure of the tooth’s root surface. This condition is common, with approximately 85% of the population experiencing some degree of recession on at least one tooth. While generalized recession affects multiple teeth, recession solely on a single tooth, known as localized recession, points toward a specific, concentrated cause. Identifying this singular factor is the first step toward effective management and prevention, requiring a professional dental diagnosis.
Aggressive Brushing and Localized Habits
A frequent cause of localized gum recession is chronic, traumatic injury from improper oral hygiene practices. This mechanical trauma occurs when excessive force is applied during brushing, especially with a horizontal “scrubbing” motion. The continuous friction physically abrades the delicate gingival tissue and underlying tooth structure at the neck of the tooth.
Using a hard-bristled toothbrush exacerbates this problem, as stiffer filaments transfer more force to the gum line. This repeated injury often manifests as a characteristic U-shaped recession defect, sometimes accompanied by a non-carious cervical lesion where the tooth surface has worn away. Recession concentrates on a single tooth because that specific area receives the most direct, aggressive contact due to the individual’s habitual brushing pattern.
Localized habits unrelated to brushing also contribute to singular recession defects. Oral piercings, particularly lip or tongue jewelry, continuously rub against the gum tissue, causing chronic irritation and mechanical stress. Similarly, habits like habitually picking at a specific gum area with a fingernail or foreign object create localized trauma.
To correct this mechanical cause, switch immediately to a soft-bristled brush or an electric toothbrush with a pressure sensor. The brushing technique should be modified to utilize a gentle, vibratory motion, such as the Modified Bass technique. This approach effectively cleans the tooth surface without exerting the abrasive force of a horizontal scrub.
Tooth Positioning and Occlusal Stress
The natural anatomy and the forces placed upon a tooth during biting and chewing are predisposing factors for single-tooth recession. When a tooth is misaligned, such as tipped outward, its root may sit too far toward the facial surface of the jawbone. This positioning results in a naturally thinner layer of alveolar bone covering the root, a condition known as dehiscence.
This thin bony plate provides minimal support for the overlying gum tissue, predisposing the area to recession even under normal oral hygiene conditions. Individuals may also possess a thin periodontal biotype, meaning their gum tissue is naturally delicate and less than one millimeter thick. This thin tissue is inherently more vulnerable to trauma or inflammation, and the prominent root is easily exposed as the tissue recedes.
Excessive or misdirected biting forces, termed occlusal trauma, can initiate or accelerate localized recession. When a single tooth absorbs disproportionate force—such as from clenching, grinding (bruxism), or a specific bite misalignment—it stresses the tooth’s supporting structures. This excessive load can lead to an inflammatory response in the periodontal ligament and supporting bone.
The body’s response to this chronic stress includes widening the periodontal ligament space and shifting the tooth’s position. This shift causes the bone and attached gum tissue to remodel and recede. Correcting the source of this bite stress, often through occlusal adjustment or a protective nightguard, is necessary to halt the progression of recession.
Specific Dental Issues and Restorations
Recession on a single tooth can stem from localized pathology or poor dental intervention, independent of generalized gum disease. While periodontitis typically affects the entire mouth, a specific, deep periodontal pocket can form on only one surface of one tooth. This localized infection and inflammation lead to concentrated bone loss and subsequent apical migration of the gum tissue in that isolated area.
Poorly fitted or contoured dental restorations are a distinct cause of single-tooth recession, referred to as an iatrogenic factor. When a crown, filling, or veneer margin extends too far below the gum line, it violates the biological width required for healthy gum attachment. This invasion causes chronic inflammation as the body attempts to push the foreign margin away, resulting in localized recession.
Restorations that are rough, unpolished, or have an overhanging edge near the gum line create a niche that traps plaque and makes cleaning impossible. This plaque accumulation leads to chronic irritation of the surrounding gum tissue. The resulting inflammatory cycle stimulates the gum to recede away from the source of irritation and bacterial challenge.
Certain dental procedures can inadvertently initiate recession. Examples include localized trauma during an aggressive professional cleaning or improper orthodontic movement that pushes a tooth too far outside the thin bony housing. Identifying and removing the specific irritant—whether a poorly contoured restoration or a deep, isolated pocket of disease—is mandatory before any soft tissue grafting procedure can be successful.