A well-made bridge commonly lasts ten to fifteen years, and plenty last longer. The failure point is almost never the porcelain. It is the supporting tooth underneath, where decay starts at the margin and works inward out of sight.
Cleaning under the bridge
You cannot floss a bridge normally, because the replacement tooth is joined to its neighbours. You need superfloss or a floss threader to get under the span, and it needs to happen daily. This is the single habit that decides whether the bridge lasts ten years or twenty.
Bridge or implant?
A bridge is quicker, involves no surgery, and makes sense when the neighbouring teeth already need crowns. The trade-off is that those teeth have to be prepared, and if one of them fails later the whole bridge is affected.
An implant leaves healthy neighbours untouched and generally lasts longer. Where the adjacent teeth are sound, it is usually the better long-term answer even though it costs more up front.