Wisdom teeth can also be impacted; that is, trapped in soft tissue and the jawbone. When wisdom teeth are not able to erupt properly, germs can enter the area around the tooth and produce an infection, resulting in discomfort, jaw rigidity, and overall illness. Because of their difficult-to-reach location and awkward orientation and partial eruption, these wisdom teeth are therefore more prone to dental decay and gum disease.
Also, because of the pressure exerted by the locked wisdom tooth, the adjacent tooth ,i.e., the 2nd molar(which has functional use) root can resorb.
All the above reasons necessitate the removal of wisdom teeth.