My girl friend has two lower jaw gaps, each gap missing two teeth. We are considering both implants and bridges. Obviously, there is a huge difference in price if we do 4 implants, plus her dentist says he wouldn't do a four unit bridge if the total width of the four teeth is more than 47 mm. There is another possibility which I suddenly thought about doing. That is having one implant filling half of each gap, waiting until the new implants heal, then having two 3 unit bridges made, again, a significant cost savings and clearly considerably narrower than 47 mm. Plus, the chances of the 3-unit bridge lasting and performing well should be better than a 4 unit bridge. What are the pros and cons of each choice?