Home  Dentistry Articles  Wisdom teeth

Wisdom teeth

Wisdom teeth are third molars that usually appear between the ages of 18 and 20 (although they may appear when older, or fail to appear at all). They are called "wisdom teeth" because they appear so late-much later than the other teeth, at an age where people are supposedly wiser than as a child, when the other teeth erupt. Often they need to be removed when they impact against other teeth-colloquially known as "coming in sideways."

Impacted wisdom teeth fall into one of several categories. Mesial impaction means the tooth is angled forward, towards the front of the mouth. Distal impaction means the tooth is angled backward, towards the rear of the mouth. Vertical impaction occurs when the formed tooth does not erupt fully through the gumline, and horizontal impaction occurs when the tooth is angled fully ninety degrees forward, growing into the roots of the second molar.

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

Pericoronitis is a common problem in young adults with partial impactions where the wisdom tooth has failed to errupt completely through the gum bed, it allows bacteria into an open space around the tooth, causing infection. Common symptoms include a swolen lump near the eruption site, bad odour or taste in the mouth and pain in the general area which may also run down the entire mandible and / or neck.

Wisdom teeth are sometimes described as an example of a "vestigial" trait that may be disappearing from our species via evolution. Others argue that recent changes to softer diets which cause less wear on the teeth may be causing the third molars to be less useful, and problematic in many humans. Alternately, it is possible that wisdom teeth were useful when it was common for humans to lose several teeth to decay by the age when they appear.

Although most people have 4 wisdom teeth, it is possible to have more or fewer. Supernumerary teeth are any extra teeth.

Extraction of wisdom teeth

Wisdom teeth are extracted for two general reasons: either the wisdom teeth have already become impacted, or the wisdom teeth could potentially become problematic if not extracted. The extraction of wisdom teeth can sometimes be performed by a regular dentist, but more often the extraction must be performed by someone who specializes in oral and maxillofacial surgery. Despite the horror stories that you may hear about having one's wisdom teeth extracted, a competent surgeon can extract your wisdom teeth with little trouble. However, there are always risks associated with surgery, and some of these risks increase when extractions are performed on patients who have kept their wisdom teeth for a significant number of years. In many cases, anesthesia will be applied.

General post-extraction problems

There are several problems that can (and in some cases will) manifest themselves after the extraction(s) have been completed. Some of these problems are unavoidable and natural, while others are under the control of the patient. The suggestions contained in the sections below are general guidelines that a patient will be expected to abide by, but the patient should follow ANY and ALL directions that are given by the surgeon in addition to the below guidelines. Above all, the patient MUST NOT disregard the instructions given to them; doing so is extremely dangerous and could result in any number of problems ranging in severity from being merely inconvienient (dry socket) to potentially life-threatening (serious infection of the extraction sites).

Bleeding and oozing

Bleeding and oozing is inevitable and should be expected to last up to a day in duration. Rinsing out your mouth during this period is counter-productive, as the bleeding stops when the blood forms clots at the extraction sites, and rinsing out your mouth will most likely dislodge the clots. The end result will be a delay in healing time and a prolonged period of bleeding. Gauze pads should be placed at the extraction sites, and then should be bitten down on with firm and even pressure. This will help to stop the bleeding, but don't overdo it as it is possible to irritate the extraction sites and prolong the bleeding. The bleeding should decrease gradually and noticeably upon changing the gauze. If the bleeding lasts for more than a day without decreasing despite having followed the surgeon's directions, contact the surgeon as soon as possible! This is NOT supposed to happen under normal circumstances and signals that a serious problem is present.

Dry Socket

A dry socket is the event where the blood clot at an extraction site is dislodged or falls out prematurely. In some cases, this is beyond the control of the patient. However, in other cases this happens because the patient has disregarded the instructions given to them by the surgeon. Smoking, spitting or drinking with a straw in disregard to the surgeon's instructions can cause this. The extraction site will become irritated and pain will mainifest at one level or another. The patient should contact their surgeon if they suspect that they have a case of dry socket; the surgeon can prescribe medication in topical form to apply to the affected site. If this is done, dry socket becomes only a mere annoyance, but without the medication dry socket can progress to an infection of the extraction site.


Swelling should not be confused with dry socket; although painful, swelling should be expected and is a sign that the healing process is progressing normally. There is no general duration for this problem; the severity and duration of the swelling vary from case to case. The instructions the surgeon gives the patient will tell the patient for how long they should expect the swelling to last, including when to expect the swelling to peak and when the swelling will start to subside. If the swelling does not begin to subside when it is supposed to, the patient should contact their surgeon immedietely. While the swelling will generally not disappear completely for several days after it peaks, swelling that does not begin to subside or gets worse may be the sign of an infection.