What type of triangle? Isosceles, scalene or equilateral? (a pedantic attempt of a knowledge of geometry.) My guess is the isosceles, with two equal sides; the base being at the gum line, the apex diving, down between the teeth. We call these gingival embrasures. They can arise due to age, periodontal disease, faulty restorations or after normal orthodontic tooth movement. The small triangular shaped gum between the teeth, called the papilla, becomes blunted, leaving a space. Treatment can consist of composite resin tooth bonding ($200 to $500 per tooth), all-porcelain crowns or veneers ($1400 per tooth). If it is localized to one area, specific periodontal surgery techniques can bulk up the papilla.What type of triangle? Isosceles, scalene or equilateral? (a pedantic attempt of a knowledge of geometry.) My guess is the isosceles, with two equal sides; the base being at the gum line, the apex diving, down between the teeth. We call these gingival embrasures. They can arise due to age, periodontal disease, faulty restorations or after normal orthodontic tooth movement. The small triangular shaped gum between the teeth, called the papilla, becomes blunted, leaving a space. Treatment can consist of composite resin tooth bonding, all-porcelain crowns or veneers. If it is localized to one area, specific periodontal surgery techniques can bulk up the papilla.