Fixed bridges and implants are often used to replace single missing teeth and to correct some kinds of bite problems.
If multiple teeth are missing, traditional removable dentures, dentures and implant dentures are used to restore such problems.
When loosing a tooth, your teeth try to correct the missing tooth by shifting in there place. This will cause future problems in your remaining teeth. Including gaps, and potential of losing more teeth.
When we lose multiple teeth our jaw will start resorbing and become smaller. This will cause a pinched smile and a shorten jaw. To prevent this, a denture or implants most be worn.