Third molars, commonly referred to as wisdom teeth, are usually the last four of 32 teeth to erupt (surface) in the mouth, generally making their appearance between the ages of 17 to 25. They are located at the back of the mouth (top and bottom), near the entrance to the throat. The term “wisdom” stems from the idea that the molars surface at a time typically associated with increased maturity or “wisdom”.
In most cases, inadequate space in the mouth does not allow the wisdom teeth to erupt properly and become fully functional. When this happens, the tooth can become impacted (stuck) in an undesirable or potentially harmful position. If left untreated, impacted wisdom teeth can contribute to infection, damage to other teeth, and possibly cysts or tumors.
There are several types, or degrees, of impaction based on the actual depth of the teeth within the jaw:
Soft Tissue Impaction: The upper portion of the tooth (the crown) has penetrated through the bone, but the gingiva (gum) is covering part or all of the tooth’s crown and has not positioned properly around the tooth. Because it is difficult to keep the area clean, food can become trapped below the gum and cause an infection and/or tooth decay, resulting in pain and swelling.
Partial Bony Impaction: The tooth has partially erupted, but a portion of the crown remains submerged below the gum and surrounding jawbone. Again, because it is difficult to keep the area clean, infection will commonly occur.
Complete Bony Impaction: The tooth is completely encased by jawbone. This will require more complex removal techniques.
Reasons to remove wisdom teeth
While not all wisdom teeth require removal, wisdom teeth extractions are most often performed because of an active problem such as pain, swelling, decay or infection, or as a preventative measure to avoid serious problems in the future. If impaction of one or more wisdom teeth is present, and left untreated, a number of potentially harmful outcomes can occur, including:
Damage to nearby teeth: Second molars (the teeth directly in front of the wisdom teeth) can be adversely affected by impacted wisdom teeth, resulting in tooth decay (cavities), periodontal disease (gum disease) and possible bone loss.
Disease: Although uncommon, cysts and tumors can occur in the areas surrounding impacted wisdom teeth.
Infection: Bacteria and food can become trapped under the gum tissue, resulting in an infection. The infection can cause considerable pain and danger.
Tooth Crowding: It has been theorized that impacted wisdom teeth can put pressure on other teeth and cause them to become misaligned (crowded or twisted). This theory isn’t universally accepted by all dental professionals, and it has never been validated by any scientific studies.