A "Bridge" in this context, is a fixed prosthesis to fill in a gap where there are missing teeth. The two teeth on either side of the missing tooth (teeth) are strengthened using porcelain crowns. They become the anchor, or abutment to the bridge. A "pontic", or fake tooth fills in the gap.
In the USA, a three unit bridge can be between $1400 and $3000, depending on the materials used and the quality of the laboratory which fashions the device. Ask about the composition...is it porcelain fused to precious metals? Do they have a replacement policy if it fails within a year or two?
There are many good reasons to fill in the spaces of missing teeth (besides looking like a prize-fighter). Teeth tend to drift or move into the empty space. The opposing teeth may grow longer as they tend to do when there is nothing hitting them when you bite or chew.
Make sure before you spend a lot of money if your dentist does a lot of this kind of thing and if he/she does good quality work. A well-made bridge should last most of your life if your gums remain healthy. (Keep up with regular dental cleanings or you'll loose all your teeth.)
Another alternative is an implant. You can consult with an implant specialist to find out if this is feasible. The cost will likely by more (at least it is in this country), but at least you will not be grinding down healthy abutment teeth to have the same result. Implants are really cool: a metal post is placed in dental bone and bone material is actually grafted on. Then, a tooth is placed that fits into the post, like a screw. It's very high-tech.
See, aren't you glad you asked? What? You didn't???
Wasa