Wisdom Teeth

Wisdom teeth are the third and final set of molars that most people get in their late teens or early twenties. Sometimes these teeth can be a valuable asset to the mouth when healthy and properly aligned, but more often, they are misaligned and require removal.

Wisdom teeth present potential problems when they are misaligned – they can position themselves horizontally, be angled toward or away from the second molars or be angled inward or outward. Poor alignment of wisdom teeth can crowd or damage adjacent teeth, the jawbone, or nerves. Wisdom teeth that lean toward the second molars make those teeth more vulnerable to decay by entrapping plaque and debris. In addition, wisdom teeth can be entrapped completely within the soft tissue and/or the jawbone or only partially break through or erupt through the gum. Teeth that remain partially or completely entrapped within the soft tissue and /or the jawbone are termed “impacted.” Wisdom teeth that only partially erupt allows for an opening for bacteria to enter around the tooth and cause an infection, which results in pain, swelling, jaw stiffness, and general illness. Partially erupted teeth are also more prone to tooth decay and gum disease because their hard-to-reach location and awkward positioning makes brushing and flossing difficult.

Your dentist or oral surgeon may recommend that your wisdom teeth be extracted even before problems develop. This is done to avoid a more painful or more complicated extraction that might have to be done a few years later. Removal is easier in young people, when the wisdom teeth roots are not yet fully developed and the bone is less dense. In older people, recovery and healing time tend to be longer.

The relative ease at which your dentist or oral surgeon can extract your wisdom teeth depends on their position. Your oral health care provider will be able to give you an idea of what to expect during your pre-extraction exam. A wisdom tooth that is fully erupted through the gum can be extracted as easily as any other tooth.

For many people, wisdom teeth emerge from the jaw between the ages of 17 and 25 years, and they don’t cause problems. In other people, the wisdom teeth become impacted, which means that they are trapped within the jaw and unable to emerge. But that’s not always a bad thing. Impacted wisdom teeth often cause no symptoms or pain and stay within the jaw for life.

But in some cases, the impacted wisdom tooth does cause problems. You may experience redness and swelling around the area where the tooth is impacted as well as jaw pain, headaches, and a strange taste when you bite near the area of the impacted tooth.

Wisdom teeth are a holdover from the earlier days of humans, when we ate a more primitive diet and needed more teeth. Humans today have smaller jaws and many of us are unable to accommodate these late-emerging teeth. As wisdom teeth try to emerge, they can push other teeth out of the way and interfere with orthodontic work. Also, partially emerged wisdom teeth can provide a breeding ground for bacteria, and bacterial buildup can lead to severe gum disease.

Even if impacted wisdom teeth are causing no symptoms, some dentists recommend removing them surgically to prevent the possibility of future problems. Fortunately, wisdom tooth extraction is a common outpatient procedure, performed under local anesthesia. As with any surgery, expect some residual bleeding, swelling and bruising in the first few days, and limit your activities. But most people recover quickly and easily.

Impacted wisdom teeth fall into one of several categories. Mesioangular impaction is the most common form (44%), and means the tooth is angled forward, towards the front of the mouth. Vertical impaction (38%) occurs when the formed tooth does not erupt fully through the gum line. Distoangular impaction (6%) means the tooth is angled backward, towards the rear of the mouth. And finally, Horizontal impaction (3%) is the least common form, which occurs when the tooth is angled fully ninety degrees forward, growing into the roots of the second molar.

Typically distoangular impactions are the easiest to extract in the maxilla and most difficult to extract in the mandible, while mesioangular impactions are the most difficult to extract in the maxilla and easiest to extract in the mandible.

Impacted wisdom teeth may also be categorized on whether they are still completely encased in the jawbone. If wisdom teeth are completely encased in the jawbone, it is a bony impaction. If the wisdom teeth have erupted out of the jawbone but not through the gumline, it is called a soft tissue impaction.

Sometimes the wisdom tooth fails to erupt completely through the gum bed and the gum at the back of the wisdom tooth extends over the biting surface, forming a soft tissue flap or lid around the tooth called an operculum. Teeth covered by an operculum can be difficult to clean with a toothbrush. Additional cleaning techniques can include using a needle-less plastic syringe to vigorously wash the tooth with moderately pressured water or to softly wash it with hydrogen peroxide.

However, debris and bacteria can easily accumulate under an operculum, which may cause pericoronitis, a common infection problem in young adults with partial impactions that is often exacerbated by occlusion with opposing 3rd or 2nd molars. Common symptoms include a swelling and redness of the gum around the eruption site, difficulty in opening the mouth, a bad odor or taste in the mouth, and pain in the general area which may also run down the entire lower jaw or possibly the neck. Untreated pericoronitis can progress to a much more severe infection.

If the operculum does not disappear, recommended treatment is extraction of the wisdom tooth. An alternative treatment involving removal of the operculum, called operculectomy, has been advocated. There is a high risk of permanent or temporary numbness of the tongue due to damage of the nerve with this treatment and it is no longer recommended as a standard treatment in oral surgery.

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