A bridge and an implant are both dental restorations used to replace missing teeth, but they differ in their approach and structure.
A bridge is used to replace one or more missing teeth. It is a fake tooth, also known as a pontic, held in place by a dental crown connected to other teeth. The dentist will drill down the adjacent enamel to fit the crowns. A bridge is made from ceramic and is cemented onto the teeth to make sure it is stable and will function for the missing tooth. A bridge is usually cheaper than an implant but not always the better option. A bridge might need to be replaced over the years and may irritate the gums. If something happens to the root of the adjacent teeth the bridge is cemented to, the bridge will have to be removed and there may be a need for an implant after all.
A dental implant is a surgical component that is inserted into the jawbone to replace a missing tooth root. It is a titanium post that is surgically inserted into the jawbone, acting as an artificial tooth root. After the implant is placed, a healing period is required for the implant to fuse with the jawbone, a process called osseointegration. Osseointegration assures the body will not reject the post. When the implant has fully healed and no issues arise, a dental crown is attached to the implant making it look like a natural tooth. An implant should last a lifetime and should not fall out. Implants are expensive but are the best investment and have a higher success rate.
As always you need to see your dentist and get a consult to see what is best for your situation.