What causes dark or black discoloration of the gums?

Children with blackened gums may experience emotional distress, becoming reluctant to smile and fearful of exposing their discolored gums. Additionally, the darkening may be accompanied by discomfort or pain, warranting prompt attention, proper management, and timely treatment. So, what causes gums to darken or turn black?

What Causes Dark or Black Gums?

Dark or black discoloration of the gums can be either physiological or pathological. Physiologically, it is primarily due to melanin deposition. Individuals with darker skin tones may naturally exhibit melanin deposits on the gums, resulting in deeper or even blackish pigmentation. Moreover, periodontal disease—characterized by dental calculus (tartar) buildup—can irritate the gums and contribute to color changes. Heavy metal deposition may also cause gum discoloration: metals absorbed systemically via the bloodstream can accumulate along the gingival margin, producing grayish or deep bluish-black linear or band-like pigmentation. Furthermore, long-term, heavy smoking can lead to melanin deposition on both the gums and tooth surfaces.

Clinically, numerous conditions can cause gum blackening. Lead poisoning, for instance, may manifest as a characteristic “lead line” (a bluish-black line) along the gingival margin, accompanied by a metallic taste in the mouth; chelation therapy is required. Mercury poisoning may produce grayish-blue “mercury lines” on the gums and cause tremors of the tongue, necessitating appropriate detoxification. Bismuth poisoning results in black gingival lines, excessive salivation, and likewise requires detoxification as the primary treatment.

Patients are advised to abstain from tobacco and alcohol, consume more fresh fruits and vegetables, and avoid spicy foods. We hope this information proves helpful.