Impactions
When your dentist tells you that your wisdom teeth are impacted, he means that they areimpeded from normal eruption by bone, other teeth or by the soft tissue/gums surroundingthe tooth. The following diagrams show the four types of impactions that wisdom teeth canalign themselves in.Mesial Impaction
Mesial impacts occur when the wisdom tooth developes tilting forward into the tooth infront.This impedes the eruption of the wisdom and it remains tilted forward. This is the most common impaction and is the easiest to extract.
Vertical Impaction
Vertical impactions occur when the wisdom tooth is unable to erupt because of lack of spaceor an abundance of fibrous tissue surrounding the crown of the tooth (usually also relatedto the lack of space). The tooth is aligned in the right crown-top, root-bottom, positionbut is unable to erupt into the bite plane. These types of impactions are the second most common impaction.
Horizontal Impaction
Horizontal impactions are uncommon and pose a challenge removing. Because of the positionof the crown against the root of the tooth infront, patients sometimes suffer from periodontal disease.
Distal Impaction
Very uncommon and very difficult to remove. The crown of the tooth resides in the bodyof the ramus (the angled portion of the jaw bone). Extraction usually requires extensive removal of bone.
Note:Images from Contemporary Oral and Maxillofacial Surgery (Peterson Ellis Hupp Tucker), published by Mosby © Copyright 1998.