Also called: Third Molars
Wisdom teeth are the third set of molars that typically emerge between the ages of 17 and 25 – the so-called “age of wisdom.” Wisdom teeth are the last teeth to erupt, and often cause problems when they finally emerge. In some cases, wisdom teeth come through the gums only partially or not at all (impaction). When a wisdom tooth is impacted, it usually must be removed (extracted).
Some experts believe wisdom teeth developed when early humans needed additional biting power to consume a rougher type of diet than that of today’s humans. Others point out that the eruption of an extra set of molar in late adolescence to early adulthood may compensate for teeth lost due to poor dental care. Over time evolution of jaw size, improvements in dental care and changes in diet have combined to reduce the space in the dental arch for wisdom teeth to emerge. This has led to complications.
In some cases, wisdom teeth emerge normally and do not cause any pain or other symptoms. However, many patients do experience symptoms. A tooth that only partially erupts creates an opening for bacteria to create an infection (pericoronitis), leading to tenderness or swelling around the gums, jaw stiffness and general illness.
Wisdom teeth that emerge in a poorly aligned fashion may damage adjacent teeth. Wisdom teeth often are difficult to reach during brushing, which can leave them vulnerable to tooth decay. In some cases, a cyst may form near the tooth that destroys bone or tooth roots.
A dental examination can reveal signs that a patient’s wisdom teeth have erupted. The dentist may take x-rays of the teeth to check for signs of impaction. If the dentist believes the wisdom teeth may be difficult to remove, the patient may be referred to an oral surgeon for further evaluation.
There are two approaches to treat impacted wisdom teeth. In the more conservative approach, the teeth are simply monitored unless they cause symptoms that begin to create problems. The more common and more active approach is to remove the teeth. Controversy remains on whether wisdom teeth that are not causing any problems should be removed.
Many dentists believe that impacted wisdom teeth are almost certain to cause problems at some point, and recommend surgical extraction regardless of whether or not the patient is experiencing symptoms. Dentists typically prefer to remove wisdom teeth when the patient is between the ages of 16 and 21, before the tooth roots become implanted in the jawbone. Adults may also have wisdom teeth extracted if they are not extracted during adolescence. Extraction usually takes between five and 30 minutes. In cases of more serious impaction, an oral surgeon may have to perform the extraction.
Following extraction, patients may experience a temporary period of minor pain, swelling and bleeding. However, the prognosis following extraction usually is excellent.
About wisdom teeth
Wisdom teeth are the third set of molars that typically erupt into a person’s mouth between the ages of 17 and 21, although they can emerge in a person’s mid-twenties. They are called wisdom teeth because of the age the teeth usually emerge, during the so-called “age of wisdom.” When these teeth are healthy and properly positioned, they help a person to chew more effectively.
However, wisdom teeth frequently fail to completely emerge through the gums, or come in sideways, tilted or otherwise positioned incorrectly. This may cause complications that can only be solved by removing the tooth. About 85 percent of wisdom teeth eventually must be removed, according to the American Association of Oral and Maxillofacial Surgeons.
Wisdom teeth erupt at the back of the mouth. By the time a person is about 9 years old, the crown of the wisdom tooth begins to develop in a small sac inside the jawbone. Most people have four of these teeth – also known as third molars – and they usually come in between the ages of 17 and 25 and are fully rooted in the bone of the jaw by a person’s 40s. The likelihood of complications developing is lessened if extraction occurs before the roots become fully imbedded in the jawbone.
Wisdom teeth are the last teeth to erupt, and as a result often cause problems when they finally emerge. In many cases, wisdom teeth come through the gum only partially or not at all (impaction). An impacted wisdom tooth may grow in sideways, emerge only partially from the gum or remain trapped beneath both the gum and the bone.
An impacted wisdom tooth usually must be removed (extracted). A tooth that only partially erupts creates an opening for bacteria to create an infection. Wisdom teeth that emerge in a poorly aligned fashion may damage adjacent teeth. In some cases, a cyst may form near the tooth that can destroy bone or tooth roots.
Many people who need to have wisdom teeth extracted become nervous because of stories they have heard about unpleasant extractions. Patients are urged to talk to their dentist about their concerns. Many dentists provide information about the process and an atmosphere designed to reduce such anxieties. For instance, patients may be allowed to listen to music or watch videos during the procedure. Relaxation techniques such as deep breathing also may help patients relax. Full sedation is also available for patients who prefer to remain asleep during the procedure.
Risk factors and causes of wisdom teeth conditions
Some experts believe wisdom teeth developed when early humans needed additional biting power to consume a rougher diet. Others point out that the eruption of an extra set of molar in late adolescence to early adulthood may compensate for teeth lost due to poor dental care. However, over time three factors have emerged that make complications related to wisdom teeth more commonplace. These factors are:
- Evolution of jaw size. Because the jaw is smaller in today’s humans, wisdom teeth do not always have the space to erupt amid all the teeth that previously erupted.
- Improvements in dental care. People do not lose as many teeth as in the past, so there is less extra room in the jaw. The emerging wisdom teeth can compress the adjacent teeth.
- Changes in diet. Modern diets include fewer tough foods. This has resulted in less wear on the teeth and reduced space for wisdom teeth to emerge.
Wisdom teeth are subject to more complications than other teeth because they are the last to erupt and have to compete for space with other teeth that are already present. People with small jawbones may be at greater risk of having impacted wisdom teeth. Otherwise, there are no known biological or environmental factors that increase a person’s risk of having impacted wisdom teeth.
Signs and symptoms of wisdom teeth problems
In some cases, wisdom teeth emerge normally and do not cause any pain or other symptoms. In other cases, wisdom teeth do not erupt, yet still do not cause any symptoms.
However, many people experience symptoms if their wisdom teeth become impacted. Untreated impacted wisdom teeth push surrounding teeth out of place or cause them to erode. Wisdom teeth may be difficult to reach during brushing, which can leave them vulnerable to tooth decay.
In some cases, a flap of gum grows over the wisdom teeth. If food and bacteria become trapped under the flap, an infection called pericoronitis may set in. If an infection sets in, patients often experience pain, tenderness or swelling around the gums, jaw stiffness, and general illness. In some cases, the infection may spread to the cheek, throat and neck. After pericoronitis occurs there is a risk of repeated infections, which may become more frequent and severe without treatment.
In some cases, the sac in which the crown of the tooth develops can fill with fluid and form a cyst. This can damage the jawbone, nerves and teeth. In rare cases, a tumor may develop. These typically are noncancerous, but may require removal of bone and tissue.
Other symptoms include:
- Bad breath (halitosis)
- Difficulty opening the jaw (trismus)
- Ongoing headache, jaw ache or ear ache
- Pain when chewing or biting
- Unpleasant taste when biting down on the tooth or the surrounding area
Symptoms may be ongoing, or may come and go. Usually, they become progressively worse over time. Patients are urged to consult their dentist if they experience swelling of their mouth, teeth, gums or jaw. Other signs and symptoms that usually require a visit to a dentist include any changes in a person’s teeth, including changes in tooth position or sensitivity of the teeth, or discoloration.
Diagnosis methods for wisdom teeth problems
A dentist typically will perform a standard visual examination to look for signs that a patient’s wisdom teeth have erupted. A patient’s dental and medical history also may be useful in making a diagnosis. Finally, the dentist may take x-rays of the teeth to look for signs of impaction. If the dentist believes the wisdom teeth may be difficult to remove, the patient may be referred to an oral surgeon for further evaluation.
Treatment options and prevention methods
There are two approaches to treat impacted wisdom teeth. In the more conservative approach, the teeth are simply monitored unless symptoms develop that begin to cause problems. Many dentists use this conservative approach if x-rays indicate that the wisdom tooth is in a normal position and therefore is less likely to cause any harm to adjacent teeth.
If minor problems occur, they often can be treated with simple techniques, such as using mouthwashes, saltwater rinses and over-the-counter pain relievers. If an infection of a gum flap (pericoronitis) is present, the dentist may remove damaged tissue and pus and give the patient antibiotics designed to kill the infection.
However, a less conservative approach may be necessary if x-rays reveal a wisdom tooth in an abnormal position beneath the gumline (making it more likely to cause problems at some point), or if the tooth is causing symptoms. In such cases, the tooth will likely need to be surgically removed (extracted).
Many dentists believe that impacted wisdom teeth are almost certain to cause problems at some point and recommend surgical extraction in all cases. However, the removal of wisdom teeth that do not seem likely to cause problems remains somewhat controversial. Dentists typically prefer to remove wisdom teeth when the patient is between the ages of 16 and 21. At those ages, the jawbone is less dense, the wisdom tooth’s roots are not as deep and large nerves are less likely to be involved in the root. These factors make extraction less difficult. In addition, younger patients are likely to experience a faster and more complete recovery. Children may have such extraction procedures before undergoing therapy with braces. However, a number of adults have the wisdom teeth removed after age 21. The healing process takes longer as people age because the roots of teeth become embedded in the jawbone in adults.
Older patients may need to have wisdom teeth extracted if they are being fitted for dentures. Wisdom teeth that erupt beneath dentures often cause severe irritation and need to be removed. This changes the shape of the gum, requiring construction of new dentures.
Patients who experience painful or worsening symptoms related to impacted wisdom teeth are very likely to require surgical extraction. If pericoronitis is present, the infection will need to be eradicated before an extraction can take place.
Typically, a patient will be asked not to eat for about six hours prior to an extraction. In addition, patients may be urged to arrange to have someone drive them home following the procedure. Whether a patient is able to drive home depends on the medications used during the extraction and the difficulty of the process. If a patient receives sedatives or general anesthesia then a ride home will be necessary.
Extraction usually takes between five and 30 minutes and usually can be performed by a dentist using local anesthetic. During the procedure, an incision is made in the gum and a forceps is used to remove the whole tooth when possible. If the tooth is fully impacted or if the roots reach deeply into the jawbone, the tooth may have to be broken into pieces and each piece removed.
In cases of more serious impaction, an oral surgeon may have to perform the extraction. This may take place in the surgeon’s office or, in some cases, in a hospital under general anesthesia. If the tooth is particularly embedded, part of the jawbone may also have to be removed.
Stitches may be necessary to close the gap in the gum. In other cases, the socket where the tooth has been removed is packed with gauze to control bleeding for 30 minutes following the procedure. The patient will likely need to rest for the remainder of the day. Smoking is prohibited for the first day following surgery to provide time for a blood clot to form in the socket to aid in healing.
Patients will be restricted to clear liquids and soft foods for the first 12 hours following surgery. Straws should not be used because they can dislodge the clot that is forming. Patients should avoid hard or crunchy foods for two weeks following surgery. They may be asked to chew on only one side of their mouths for a period of time.
Patients are urged to rinse their mouths with warm salt water a half-dozen times after the first day following extraction. The salt water should be made up of a half-teaspoon of table salt and 8 ounces (236 milliliters) of water. Patients can brush their teeth, but they should be careful around the area where the tooth was removed.
Ice packs and over-the-counter pain relievers usually are used to control pain and swelling. In some cases, prescription pain medication may be necessary to control pain. It is normal for bleeding to occur during the first day following extraction. Patients are urged to swallow this blood, so as to avoid dislodging the forming blood clot.
In some cases, complications may develop. They include:
- Dry socket. This is a painful condition that occurs when the socket’s blood clot dislodges and the underlying bone becomes exposed. It can be prevented by closely following post-extraction instructions (e.g., no smoking or alcohol). If dry socket develops a dentist should be consulted immediately for treatment.
- Infection. This occurs as a result of bacteria or trapped food particles.
- Sinus problems. These occur when teeth near the sinuses are removed.
- Temporary numbness of the teeth, gums, tongue and chin.
- Weakening of the jawbone. This occurs as a result of bone removal or damage.
There is no way to prevent the problems associated with a wisdom tooth. However, careful oral hygiene such as regular brushing and flossing can help reduce the risk of tooth decay, infection or other complications.
Questions for your doctor about wisdom teeth
Preparing questions in advance can help patients to have more meaningful discussions regarding their conditions. Patients may wish to ask their dentist the following questions related to wisdom teeth:
- I’m in my teens. If my wisdom teeth do not cause problems, should I have them removed anyway?
- What are the disadvantages of waiting to have them removed?
- What are the possible risks associated with extraction?
- If I do not have them removed, what complications might I experience later?
- How should I prepare for the extraction?
- Will I need an oral surgeon to perform my procedure?
- Can I have general anesthesia so I won’t be awake for the procedure?
- How should I modify my behavior following extraction?
- How long will it be before I can eat on the side of my mouth with the removed tooth?
- What should I do if I experience prolonged pain following the procedure?