What Is an Impacted Tooth?
An impacted tooth is one that fails to pass through the gums or emerges only partially. “Impacted teeth are part of a greater category of unerupted teeth,” says Allan J. Kucine, DDS, Associate Dean for Clinical Affairs and Acting Chair, Department of Oral & Maxillofacial Surgery, Stony Brook University School of Dental Medicine. “An impacted tooth is a tooth that is prevented from erupting fully into the dental arch.”
Impacted teeth can occur when there’s no room for a tooth to enter the dental arch due to overcrowding. Sometimes the jaw is simply too small to accommodate the tooth, particularly in the case of third molars, also known as wisdom teeth. Bone, tissue or surrounding teeth can also obstruct a tooth, preventing it from coming into the dental arch.
Most impactions occur with the permanent teeth, and the condition is very common. The American Association of Oral and Maxillofacial Surgeons (AAOMS) reports nine out of 10 people have at least one impacted tooth. Evaluating children early on can help identify the problem and prevent damage. “The American Association of Orthodontists recommends all children be seen by age 7,” says Hampton, Va., orthodontist, Catherine Oden Fulton, DDS. This includes a complete dental examination along with a panoramic x-ray.
Problems Associated with Impacted Teeth
Some patients with impacted teeth are pain free, while others experience severe pain, pressure or gum tenderness. Over time, even impacted teeth with no apparent symptoms can lead to problems.
Pressure from crowding or abnormal positioning of the impacted tooth can eventually cause pain and damage to surrounding teeth. Partially impacted teeth are often difficult to clean, leading to decay or infection in adjacent teeth. And trapped food and plaque can increase the risk of pericoronitis, an inflammatory gum condition. “When a tooth is partially impacted, it creates a very easy scenario for food debris to accumulate,” Kucine explains.
“The sac of tissue surrounding the impacted tooth can develop cysts or tumors,” says Kucine. “They are almost always benign, but can be very aggressive and occupy a large portion of the patient’s jaw.” Cysts can become so large that they eventually can damage or move adjacent teeth.
Removal and Other Treatment Options
“Wisdom teeth are the most commonly impacted tooth, and the canine, or eyetooth, can also become impacted,” says Kucine. Impaction of the second molars is much less common and is estimated to occur in only three of every 1,000 patients.
As an orthodontist, Dr. Fulton says the impacted teeth she deals with most often are the canines and second molars. Treatment options for impacted second molars can include removal of the tooth or a combination of oral surgery and orthodontic treatment to move the tooth into its proper position. “As soon as a 12-year molar is visible in the arch, we can see on a radiograph if it’s impacted,” says Fulton, who credits newer orthodontic techniques and improved wire products with making it easier to upright tipped second molars than in the past.
With the exception of the third molars, the maxillary (upper) canine teeth, sometimes called the fangs or eyeteeth, are typically the last teeth to erupt and usually appear around the age of 13. They are the second most frequently impacted teeth (after the wisdom teeth) and the majority of impacted upper canines come in on the roof side of the dental arch.
Children should be carefully examined for any signs that indicate the canines could become impacted, so steps can be taken to lessen the complexity of treatment. The removal of extra teeth may be required to eliminate crowding, and braces may also be used to ensure the tooth erupts properly.
Wisdom teeth are the final molars to erupt and usually appear in the late teens or early twenties. Even when there is room to accommodate the additional teeth, many dental experts recommend removal of the third molars, since later complications can arise. The AAOMS estimates approximately 85 percent of third molars will need to be removed at some point. Early removal is preferred, since the bone is more flexible at that time and patients often experience better healing.