People with missing teeth have their lips and cheeks collapsing inwards. Additionally, missing teeth shortens the natural distance between their nose and chin. As a result, tooth loss makes people look a lot older than they actually are.
The sunken and aged appearance of people affected with tooth loss is mainly a result of two factors. First off, losing a teeth directly translates to losing the anatomical framework that supports the soft tissues of the both the lips and cheeks. Secondly, and perhaps more importantly, tooth loss eventually leads to jawbone deterioration.