Wisdom teeth are formally known as third molars. These teeth are commonly referred to as wisdom teeth because they appear so late, much later than the other teeth, at an age where people are presumably "wiser" than as an adolescent, when the other teeth erupt.
Wisdom teeth are the most common missing teeth followed by upper lateral incisors, lower second bicuspids and upper second bicuspids. Therefore, patients can present with zero to four wisdom teeth.
A complete dentition includes 32 teeth including the wisdom teeth, eight teeth per quadrant. Unfortunately, most of us only have jaws large enough to accommodate at most 28 teeth.
Most importantly, let’s be clear that wisdom teeth are not responsible for causing crowding/relapse of other teeth from pushing from behind. Changes in the alignment of mostly commonly the lower front teeth, are a result of late growth or aging changes.
The reason I assess wisdom teeth in my practice is to determine whether or not there will be adequate space for them to erupt fully into the oral cavity and be cleansable functional teeth. If there is only enough room for them to erupt partially and part of the tooth remains covered by bone and/or gum tissue, then they are not maintainable because food and bacteria can access the tooth and cause decay or infection. Even patients with immaculate oral hygiene cannot access these covered areas to cleanse them. It is better to remove these teeth preventatively rather than risk that later they have to be extracted under emergent circumstances when the success rate of removal without negative sequelae is significantly reduced.
The optimal time to have the wisdom teeth removed is when they are un-erupted, at the bone’s surface and soft tissue covered. This permits the oral surgeon to open an access, remove the tooth and close the wound. A closed wound heals significantly better than an open wound anywhere in the body, the mouth is no exception. If extraction is delayed until after the teeth are erupted, an open socket is left behind, and the surgeon cannot suture the sides of the socket together. The open wound is at risk of developing a dry socket (failure for a blood clot adhere and begin healing) or worse become infected. It is difficult for healing to occur while simultaneously trying to keep the surgical site clean, especially as food is continuously being impacted into the socket during eating.
Another reason to remove the wisdom teeth at the recommended staging advised above is that they have not completed their root development. In the lower arch, when the roots are fully developed they will be in close proximity to the inferior alveolar nerve. The inferior alveolar nerve runs along the border of the lower jaw and supplies sensory innervation to the lower lip and chin. Removing the wisdom teeth when the development of their roots are complete increases the risk of there being some degree of paresthesia.
Upper wisdom teeth often have a greater chance of fitting but without their lower counterparts they have nothing to oppose them and these teeth will over-erupt or super-erupt beyond the plane of the bite or occlusion until they oppose something, in all likelihood the gums in the lower arch. Therefore, in almost all instances either all four wisdom teeth need to be either retained or removed.
To have your wisdom teeth assessed with a panoramic image, please contact either your dentist, orthodontist, or an oral surgeon. Note: Not all dental practitioners have panoramic x-ray machines in their offices.