Wisdom teeth, officially known as third molars, are the last teeth to develop in the mouth. They are positioned at the very back of the jaws, with one in each corner. They typically complete their development and eruption process between the late teens and the early twenties. This period often coincides with the end of skeletal growth.
The Typical Timeline of Wisdom Tooth Eruption
The development of the third molars begins deep within the jawbone during childhood, often becoming visible on X-rays around ages seven to ten. By the time an individual reaches approximately age twelve, the crown, which is the top visible part of the tooth, is largely formed. This preparatory phase occurs entirely beneath the gums before any noticeable movement begins.
The actual emergence, or eruption, of the wisdom teeth usually takes place between 17 and 25 years old. This age range is considered the standard window for the third molars to break through the gum tissue and move into their functional position. Full eruption is a slow process that can take a few months to a year once the tooth begins to push through the gums.
By age 25, approximately 90% of wisdom teeth that will erupt have done so, reaching a definitive stage in their development. However, individual variation is common, and some people may experience eruption into their late twenties or even early thirties. The completion of this chronological timeline signifies the end of the tooth’s upward movement.
The Biological Mechanism of Growth Cessation
A tooth stops growing when its root structure is fully formed and the tip of the root, called the apex, closes. The dental pulp, which is the soft tissue inside the tooth, is responsible for building the hard tissue of the root. During the eruption phase in the late teens, the roots of the wisdom teeth are often only partially formed, sometimes only one-third to two-thirds complete.
Root lengthening continues for several years after the crown has erupted or attempted to erupt. A wisdom tooth is considered fully mature and finished with its growth phase once the root tip is entirely closed and anchored in the jawbone. This physiological completion typically occurs in the early to mid-twenties, a few years after the crown initially appears.
The process of root completion is significant because the surrounding jawbone becomes denser as a person ages, particularly by the mid-twenties. If removal is necessary, operating on teeth with fully formed and deeply anchored roots is generally more complex than removing those with immature roots.
When Growth Doesn’t Follow the Rules (Impaction and Late Movement)
The perception that wisdom teeth continue to move years after the typical timeline is often due to a complication called impaction. Impaction occurs when the tooth is prevented from fully erupting into the correct position due to a lack of space or an improper angle of growth. This failure to emerge can happen even after the tooth’s physical root growth has stopped.
Even when the root formation is complete, an impacted tooth can continue to exert pressure on the surrounding teeth and bone tissue. This pressure can cause pain, shifting of other teeth, infection, or damage to the adjacent molar, leading to the sensation that the tooth is still active or “growing.” In these cases, the ongoing issues are related to the tooth’s trapped position and its effects on surrounding structures, not the biological growth of the tooth itself.