There are several types of bridges including conventional fixed bridges, cantilevered bridges and resin bonded bridges.
With the first two types, the adjoining teeth are prepared to receive crowns. A porcelain tooth is placed between the crowns and permanently joined. Resin bonded bridges require less alteration of the adjacent teeth and are most commonly used in front teeth. Your dentist will discuss the best type of bridge for you.
Crowns and bridges are available in all porcelain, porcelain over gold or all gold. Your dentist will discuss these options with you to determine what's best for you.