One way to replace a missing tooth is dental bridge. At its simplest form it is a combination of 2 crowns which are connected in the middle to another crown form called Pontic. Those 2 crowns on both sides which hold the bridge in place are called Abutments. Usually we are limited with the number of teeth we can replace in this way as the longer the bridge gets, more pressure will be applied on abutment teeth during chewing. Also another limitation for bridge is when we need to replace a missing tooth which there is just one tooth next to it and not 2 teeth on both side of it. We call that a free end gap. In case of free end gap we have to think of replacing the missing tooth/teeth with denture or implant.
The same as crown, bridge can be made of many different materials. In the past we could have full metal or porcelain fuse to metal bridges. These days we have more options which provide us better aesthetic like full Zirconia, full porcelain or porcelain fuse to Zirconia. Each of these have its own advantages which can be used for the right case.