Impacted wisdom teeth a small minority (less than 2%) of adults age 65 years or older maintaining the teeth without caries or periodontal disease and 13% maintaining unimpacted wisdom teeth without caries or periodontal disease. Periodontal probing depths increase over time to greater than 4 mm in a significant proportion of young adults with retained impacted wisdom teeth which is associated with increases in serum inflammatory markers such as interleukin-6, soluble intracellular adhesion molecule-1 and C-reactive protein. Crowding of the front teeth is not believed to be caused by the eruption of wisdom teeth although this is a reason many dental clinicians use
Impacted wisdom teeth of the 3rd molar. Wisdom teeth likely become impacted because of a mismatch between the size of the teeth and the size of the jaw. Impacted wisdom teeth are classified by their direction of impaction, their depth compared to the biting surface of adjacent teeth and the amount of the tooth's crown that extends through gum tissue or bone. Impacted wisdom teeth can also be classified by the presence or absence of symptoms and disease. Screening for the presence of wisdom teeth often begins in late adolescence when a partially developed tooth may become impacted. Screening commonly includes clinical examination