Advances in ceramic technology now make it easier to have a  metal free smile. Traditional fillings and crown or bridge restorations often were metal or had a metal base on which porcelain was bonded. It is now possible to have an all porcelain crown, bridge, or filling placed with no trace of metal that can gray or darken your smile. All-ceramic restorations allow transillumination and let your teeth "light up" much like natural teeth will.