Removal of "black-line" margins and improving esthetics of porcelain-fused-to-metal crowns: update in technique.

A repair technique is presented for elimination of "black line" crown margins and extension of margins onto cervical surfaces. A resin bonding agent that adheres simultaneously to metal, porcelain, and dentin is utilized to expedite completion of the repair. The bonding resin is opaqued with a light-curing, filled resin and then covered with a suitable composite resin. This technique updates a previously published technique by eliminating glass-ionomer cement liners and liner etching and improves both efficiency and esthetics of the repair.