A bridge is an artificial tooth supported by the teeth on either side of the space.
Your dentist shapes the teeth on either side of the gap, and takes a mould which is sent to a dental technician. The dental technician to make the bridge. In the meantime you have some plastic tooth-like temporary covers on the teeth. The dental technician makes the complete structure, using porcelain (for appearance) and a metal core (for strength). Your dentist then removes the temporary covers and checks the fit and bite then cements the bridge onto the teeth. Bonded bridges that do not require shaping of the neighbouring teeth are sometimes used. These have advantages and disadvantages which you and your dentist can discuss. Stronger materials are sometimes necessary for bridges used in back teeth. Your dentist may use an all-metal, gold bridge for this. A bridge is a long term, very attractive way of helping you fill the gap.