Trung TH, Lâm LN, Thuỵ PAV. Histological survey of gingival hyperpigmentation. TCNCYH [Internet]. 2026Mar.9 [cited 2026Nov.11];199(2):660-6. Available from: https://tapchinghiencuuyhoc.vn/index.php/tcncyh/article/view/4712