To close black triangles in the gingival embrasure when restoring teeth with veneers or crowns, there are clinical and technical design procedures required before preparing the tooth or manufacturing the restoration. This article focuses on the clinical portion of the preparation design.

First, plan on extending the tooth preparation subgingivally. The depth will depend on the volume of space that needs to be closed. The larger the space, the deeper that margin will need to be placed intracrevicular. The maximum depth should not exceed one-half of the measured sulcus depth.

Second, if a veneer restoration is planned, the interproximal finish line must extend palatal to the interproximal contact. The larger the space, the further the preparation will extend toward the palatal aspect of the tooth.

By designing the tooth preparation as described, the technician can design the final restoration with a convex morphology to close the space and create a cleansable restoration.