Anthropologists believe that wisdom teeth, our third set of molars, were needed by our ancestors to chew through their diet of rough, coarse food. Wisdom teeth have no function in processing today’s softer foods. For tougher foods, we favor modern utensils, such as forks and knives, to help us reduce food to smaller, chewable pieces. Wisdom teeth are classified as vestigial body parts that have been rendered useless by evolution.
Wisdom teeth erupt much later in life than other teeth. They usually surface between the ages of 17 and 25, the time when people have reached a new level of maturity, hence the term wisdom teeth.
The development of teeth, from the primary to the permanent set, takes place in a very organized fashion. It takes several years before a person has a full set of teeth. The first molars typically surface when a person reaches age 12. Wisdom teeth don’t even start forming until about age 10, and it takes from seven to 15 years before they fully form and erupt.
People may have from one to four wisdom teeth. There is no firm explanation as to why people develop differing numbers of wisdom teeth. Some people never grow them at all and escape the pain and inconvenience of having them removed. On other rare occasions, people could have more than four wisdom teeth. The bonus tooth or teeth come with bonus problems. In the case of wisdom teeth, less is usually more.
As a result of evolution, the human jaw has become smaller compared to the jaws of ancient people. Wisdom teeth in a smaller human jaw can create a cascade of problems. At times, the wisdom teeth may be blocked by the teeth around them. They may not be able to erupt or may only break through partially. With a partially-erupted wisdom tooth, food can get trapped in the surrounding gum tissue, leading to bacterial growth and serious infection.
When wisdom teeth do not erupt and remain tucked under the gums, problems can result, including displacement of permanent teeth or teeth crowding. Cysts could also form in the soft tissues around the impacted wisdom teeth, resulting in the destruction of the bones, expansion of the jaw, or damage to the surrounding teeth.
Some people are lucky enough to have well-developed wisdom teeth that function just like the other molars, but there is no guarantee that the wisdom teeth won’t present problems later. It is estimated that around 85 percent of wisdom teeth need to be removed because they create dental problems. Talk to your dentist if you suspect your wisdom teeth are coming in, or if they have already erupted.