A Case Study
When someone has missing teeth, one of the ways to restore the mouth is to make a fixed bridge. This requires putting a crown on existing teeth and having missing teeth attached to them. The only rule is that you can’t have replacement teeth just hanging off of a crowned tooth without having support on the other side of the space (like a bridge that starts to go over water but doesn’t make it to the other side).
Today I had a 50 year old female patient come in who had such a bridge. She is missing a tooth next to her canine tooth in the front, plus 2 more teeth missing behind the same canine. She was complaining that the bridge was loose. It is possible that the cement seal can break and the bridge can be recemented. That would be a nice and simple solution. In this case, the bridge broke where just behind the canine. The actual crown on the canine is fine and intact, but I could floss between that tooth and the space behind it. So, the front is no longer supporting the 2 missing teeth behind it.
There is no simple fix for this. The bridge can only be salvaged for the front missing tooth. For the space behind the canine, 2 implants can be placed, and perhaps the crown that supported the tooth in the back can be salvaged. By the way, this is the best solution for this situation these days with the great improvement and predictability of implant restorations. At the time she had this done, 15-20 years ago, implants were not as popular. But now there are VERY few implant failures, and I expect these to last very long, probably for the extent of her life.