From a technical point of view this is possible, however, it is not recommended. These structrures often break. Your own tooth has a periodontal ligament that allows a small amount of movement. An implant, however, allows NO movement whatsoever because it is anchored rigidly to the bone. Because of the difference in movement then all presure is applied onto the implant as a result of which the screw in the implant can become damaged and the implant can even break. The natural tooth usually comes loose from the bridge as a result of which it becomes decayed.