Black triangle is common phenomenon inanterior teeth, this open gingival embrasure may contribute to unaesthetic problems, pronouncing trouble and food retention, even more, it can adversely affect the health of the periodontium. With the improvement of self-care awareness and aesthetic requirement, the aesthetics of periodontiumare concerned by more and more people. This article reviews the etiology, risk factors from literatures, in order to give the reference to clinic.
