When a tooth is impacted, it means that the tooth either has not come in as expected, or that the tooth cannot erupt above the gumline for some reason. For example, the tooth might not have room to come in; or it may be coming in the wrong direction or position.
Wisdom Teeth are the most common type of teeth found to be impacted, but it can happen to other teeth as well. Sometimes you might need to have a baby tooth extracted to make room for the permanent tooth. In other cases, you might need a combination of oral surgery and orthodontic treatment to bring a tooth into the proper position.