What are wisdom teeth and why are they so often removed?

They are the last teeth to develop and the last to appear as we reach maturity. Sometimes they don’t appear, but become impacted inside the jaw. This occurs because our jawbones have a finite amount of space for teeth, and since wisdom teeth are the last to erupt, there might not be enough space left for them.
When there is a space problem and poor alignment or impaction, it is usually best to remove the wisdom teeth, preventing future problems that could include infection in the jaw or premature loss of the healthy teeth ahead of the wisdom teeth.
Some people believe that impacted wisdom teeth can cause the lower teeth to start to cross over and become misaligned, but this has never been proven to be the case.