When the interdental papilla (gingival triangle) between teeth recedes due to aging or periodontal disease, “black triangles” form at the neck of the teeth, which both impairs aesthetics and leads to food retention. The most critical point when closing these gaps with composite bonding is to design a very smooth emergency profile and to ensure the restoration does not extend beyond the biological width (junctional epithelium and connective tissue adhesion boundary) below the gum line. If the composite material is excessively overhanging or stepped, it can trigger chronic plaque accumulation, gingivitis, bleeding, and even alveolar bone resorption; therefore, matrix systems (e.g., Bioclear matrices) must be used to meticulously shape the anatomical form under a microscope or magnifying glass without damaging the gums.
