A. It sounds as though you have had gum surgery.  This can often lead to ” black triangles” at the gum margin between the teeth.  The gum is in its position due to the underlying bone supporting it.  Bone defects that are vertical in nature and localised can sometimes be grafted to allow better support of the gum lying above to improve the appearance.  Horizontal defects are not possible to repair when they are generalized, as in the case when extensive gum surgery is required.  The only way to improve the appearance is by disguising the problem with carefully placed veneers or crowns to close the triangles – this must be done only following resolution of the gum problem and must not be the cause of relapse of the gum disease.