Wisdom ToothWhat Are “Wisdom Tooth?”

“Wisdom teeth” are a type of molar. Molars are the chewing teeth found furthest in the back of the mouth. Most humans have first, second, and third molars.

A person’s third molars are their wisdom teeth. These teeth come in behind the 2nd molars (if there is room for them and they are aligned properly) usually during a person’s late teens or early twenties. Usually there are four wisdom teeth: upper left, upper right, lower left, and lower right.

wt2What Are “Impacted Wisdom Tooth?”

In dental terminology an “impacted tooth” refers to a tooth that has failed to emerge fully into its expected position. This failure to erupt properly may occur either because there is not room enough in the jaw for the tooth, or because the angulation of the tooth is improper.

Classification of Impacted Wisdom Tooth.

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Dentists use specific terms to describe the positioning of impacted wisdom teeth. The most common type of impacted wisdom tooth is one that is impacted mesially. The term “mesial” simply means that the wisdom tooth is angled forward, toward the front of the mouth.

In addition to mesially, vertically, horizontally, and distally impacted, wisdom teeth can also be classified as soft tissue or bony impactions. The term “bony” impaction indicates that the wisdom tooth is still fully encased in the jaw’s bone. A “soft tissue” impaction is one where the upper portion of a wisdom tooth (the tooth’s crown) has penetrated through the bone, but has not yet erupted fully through the gums.

Why might Wisdom Tooth be Impacted?

The reason why some wisdom teeth are impacted is not an easy question to answer. A primary cause of wisdom tooth impaction is simply that there is inadequate jawbone space behind the person’s second molar. Why this lack of space exists is not fully understood, however there does seem to be a correlation between large tooth size, tooth crowding, and the presence of impacted wisdom teeth.

  • Pain or Tenderness of the gums (gingiva)
  • Unpleasant taste when biting down on or near the area
  • Visible gap where a tooth did not emerge
  • Bad breath
  • Redness and swelling of the gums around the impacted tooth
  • Swollen lymph nodes of the neck (occasionally)
  • Difficulty opening the mouth (occasionally) 
  • Prolonged headache or jaw ache. 

 

What can happen if impacted Wisdom Teeth are not treated?

wt4Serious problems can develop from partially blocked teeth such as infection, which may turn life threatening and possible crowding of, and damage to adjacent teeth and bone. Another serious complication can develop when the sac that surrounds the impacted tooth fills with fluid and enlarges to form a cyst causing an enlargement that hollows out the jaw and results in permanent damage to the adjacent teeth, jawbone and nerves. Left untreated, a tumor may develop from the walls of these cysts and a more complicated surgical procedure would be required for removal.

Rare instances have been found when the impacted wisdom teeth remain asymptomatic without causing any problems. However, no prediction can be made as to when an impacted molar will cause trouble, but trouble will probably arise, and that too at inconvenient times. When it does, the circumstances can be much more painful and the teeth can be more complicated to treat. Here, the tooth cannot be removed until the infection or other complications have been treated. This means loss of more time and added expense along with some added risk. It’s best to have impacted teeth removed before trouble begins.

X-rays of the wisdom teeth are made to help assess the positions, shapes and sizes of the crowns and roots, the surrounding bone and the nerve, which usually runs below the roots of the teeth. X-rays also help in identification of associated disease conditions such as cysts and tumors in relation to the teeth, apart from aiding in planning of the surgical procedure.

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Orthopantomogram (OPG Xray) showing bilateral impacted lower wisdom teeth

In certain cases of impacted teeth, where there seems to be adequate space available for eruption, the dental surgeon may advise a pericoronal flap excision (removal of the gum tissue overlying the impacted tooth) and observation. In such cases, the tooth may erupt into place after the procedure. However, in many cases, infection of the overlying gum tissue has been found to recur. Here, there is no other choice other than the removal of the offending wisdom tooth.

In light of the clinical experience that most impacted teeth will ultimately give rise to some type of problem or disease, it is generally felt that preventive removal of impacted third molars is indicated. Because complications are significantly reduced when the impacted tooth has no associated disease conditions, and because difficulty of removal increases with age, it is recommended that impacted teeth be removed early. It is best done as soon as it becomes apparent that there is insufficient space or that they are not positioned for normal eruption. Generally, this will occur somewhere between the ages of 16-18. At this age, the roots of the developing tooth are usually between one half to two thirds formed and the bone is less dense, which makes their removal easier and the post-operative recovery smoother. A young patient usually is also in optimal general health, which facilitates safe anesthesia and rapid, complete healing. In older patients, removal before complications develop is key to shorter recovery and shorter healing time, besides minimizing discomfort after surgery.

Before the removal of the impacted wisdom tooth, the patient is normally put on a course of antibiotics and anti-inflammatory drugs to eliminate existing infection and inflammation in the area. The removal of an impacted tooth is normally a minor surgical operation, lasting 10 – 45 minutes. It often requires incision of the gum, cutting the tooth and probably some removal of bone too. The oral surgeon may provide anesthesia options of local anesthesia, intravenous sedation, or general anesthesia to make the procedure more relaxing for the patient. The surgical wound is often sutured with silk (non-absorbable) or with absorbable suture materials. Some surgeons advise extraction of the corresponding upper wisdom teeth also during the same sitting.

wt6This reasons for having one’s wisdom teeth removed adopt a philosophy that if a wisdom tooth does not or cannot erupt into proper position then the tooth has few benefits to offer and instead will be a potential source of problems. Listed below are some of the types of problems that can develop in association with impacted wisdom teeth.

Recurring Pericoronitis.

A condition that often occurs when wisdom teeth are impacted is pericoronitis. The term pericoronitis specifically refers to an infection located in the tissues that surround a tooth that has not fully emerged through the gums and into its proper position (this type of tooth positioning would be termed “partially erupted”).

Gum tissue attaches at pretty much the same level on all teeth. This means that if just a portion of a wisdom tooth has poked its way through the gums an opening will have been created that connects the space that lies between the gums and the crown of the submerged wisdom tooth and your mouth. (The “crown” portion of a tooth is the “non-root” part, the portion of a normally positioned tooth that is visible above the gum line. Gum tissue is never attached to the crown portion of a tooth.)

Dental plaque will accumulate in this space and, unfortunately, there is no way for a person to effectively clean it out. As a result from time to time the bacteria contained in the dental plaque can cause an active infection, which then spreads to the tissues surrounding the wisdom tooth. Dentists give the name “pericoronitis” to this type of infection.

wt7The signs of pericoronitis are tenderness and swelling in the gums surrounding a wisdom tooth. There can also be severe pain, an unpleasant mouth odor, and even a bad taste coming from the infected area.

Persons who have pericoronitis should be seen by their dentist. In most cases a dentist will place a patient on antibiotics and, if possible, show them methods by which they can flush out the space between the tooth and gum (the area that harbors the bacteria causing the infection).

Even wisdom teeth that are destined to eventually come into proper alignment will go through a transitional period where they are only “partially erupted.” This is because it takes some time for a tooth to fully penetrate through the gums and achieve its final positioning. During that time frame when a wisdom tooth is only part way through the gums it is at risk for developing pericoronitis.

A dentist who evaluates a patient when pericoronitis is present will have to determine whether the pericoronitis seems to just be associated with a transitional phase of the normal eruption process of the wisdom tooth or if the wisdom tooth is impacted, and therefore it is likely that pericoronitis will be a recurring phenomenon. In the later case, extraction of the offending wisdom tooth is usually indicated.

Cavities get a chance to form in teeth when dental plaque is allowed to remain on a tooth’s surface for prolonged periods of time. If the position of a wisdom tooth is one where you are not able to clean it thoroughly, then the tooth will be at risk for developing decay.

If tooth decay does form wisdom teeth they often can, just like with any other teeth, have their cavities fixed by way of a dentist placing a filling, especially in those cases where the amount of decay is small. Sometimes, however, a dentist will advise against filling a wisdom tooth. In these cases the decay found on the tooth can be in such an awkward location that the dentist does not feel that they can access that part of the tooth adequately so to place a filling. As you can imagine, if a tooth has been hard for you to clean it is likely your dentist will have the same problem of access also.

Even if a filling has been successfully placed, if a wisdom tooth still cannot be cleansed properly and plaque is allowed to continue to accumulate on its surface you run the risk of developing recurrent decay. The term “recurrent decay” simply means that a new cavity has formed on an aspect of a tooth adjacent to an existing filling. For all of these reasons, if a tooth can’t be cleansed properly and a cavity has formed it is quite possible that the best, and possibly even the easiest and cheapest, solution is to have the tooth extracted.

wt8Poorly aligned wisdom teeth can have a positioning that creates a trap for plaque and debris between the wisdom tooth and the next molar forward (the 2nd molar). Because this debris trap cannot be cleansed properly not only is the wisdom tooth that is placed at risk for developing decay but the 2nd molar is also. The worst case scenario in this type of situation is that decay will begin on both teeth and it will advance to such a great extent that both the wisdom tooth and the 2nd molar will need to be extracted.

Whenever a tooth cannot be properly cleansed (brushed and flossed), the bacteria found in the dental plaque that accumulates on and around the tooth can lead to the formation of periodontal disease (“gum disease”). If allowed to advance, periodontal disease can significantly damage not just the gums but also the bone surrounding the tooth. Enough damage can occur that the tooth may need to be extracted.

It may seem a bit of a conundrum that a dentist will recommend the removal of a wisdom tooth now just so you won’t develop periodontal disease around it and subsequently have to have the same wisdom tooth extracted later. What you need to realize is that a portion of the gum tissue that surrounds a wisdom tooth is the same tissue (and bone) that abuts the backside of the next molar forward (the 2nd molar). Gum disease is not an isolated event occurs around an individual tooth, it also affects a tooth’s neighboring teeth. It would be a shame to damage or lose a valuable 2nd molar simply because a wisdom tooth you could not clean properly was not extracted.

While it is not a common occurrence, cysts and tumors can develop in the tissues associated with impacted wisdom teeth. (If a decision is made to not remove an impacted wisdom tooth a dentist will often recommend that a x-ray should be taken of the tooth periodically. This allows the dentist to evaluate the tooth and its surrounding tissues for changes that might suggest a cyst or tumor is forming.)

There is a theory that suggests that impacted wisdom teeth, as part of their effort to come fully into place, can put pressure on a person’s other teeth and cause them to become misaligned (crowded and shifted). Changes in the alignment of a person’s lower front teeth, especially, are frequently blamed on pressure created by a person’s wisdom teeth.

This theory, while possibly being true, has never been conclusively proven by scientific studies and is not universally accepted by the dental profession. This is not to say that people don’t have teeth which do shift, but rather that the shifting that does occur has not been scientifically proven to be caused by a person’s wisdom teeth coming in.

wt9While uncommon, the attempted-eruption of a misdirected impacted wisdom tooth can cause damage to a person’s 2nd molar (the next tooth forward of the wisdom tooth).

This event is somewhat similar to what happens to baby teeth. Baby teeth, when they fall out, look as though they have no root portion. The tooth did have a root at one time, but the action of the permanent tooth erupting underneath the baby tooth causes the resorption of the root, hence the baby tooth looks rootless.

Similarly, when misdirected wisdom teeth attempt to erupt they can cause resorption of the root of the 2nd molar. The worst case scenario in this instance is that both the offending wisdom tooth and the damaged 2nd molar will have to be extracted.

What are the problems the patient faces after the surgical removal of impacted Wisdom Teeth?

Swelling, mild pain, mild bleeding (ooze) from the surgical site and restriction in mouth opening are common problems, which the patient faces after surgical removal. This may be associated with tenderness in the area and difficulty while swallowing. Normally these problems are found to gradually increase after the surgery reaching the maximum by 12–24 hours post-operatively. These problems gradually decrease over the next one-week almost disappearing totally, after suture removal after 1 week in case of non-absorbable sutures. There may be instances where problems persist for longer periods.

The patient should report back to the surgeon if the following problems are seen persisting or increasing even after a period of 4 days after surgery – bleeding, severe pain, swelling, restriction in mouth opening, loss of sensation over the chin and lips, inability to chew properly, jaw joint pain etc.

Are there any complications or risks associated with the surgical removal?

In rare instances, numbness or odd sensation of the lower lip, chin or tongue may occur. The nerves involved are sensory so there is no change in appearance or function. Numbness can last from a few days to several months and in extremely rare instances can be permanent. However, recovery is usually uneventful. Usually X-rays made prior to the surgical procedure helps predict the possibility of involvement of the nerve with respect to the surgery. However, this is not applicable in all cases. Very occasionally, a filling in the tooth next to an impacted tooth may be dislodged or the adjacent tooth broken, in spite of immaculate care and technique. Filling of the ensuing defect may solve the problems once the surgical wound heals. Rarely, pain and/or sensitivity of the adjacent second molar tooth may also occur, which can be totally rectified. It will not cause any hollowing of the cheeks as many people suspect.

Potential complications include postoperative infection, temporary numbness from nerve irritation, jaw fracture, and jaw joint pain. An additional condition, which may develop, is called dry socket. This happens when a blood clot does not properly form in the empty tooth socket, or is disturbed by an oral vacuum (such as from drinking through a straw or smoking), the bone beneath the socket is painfully exposed to air and food, and the extraction site heals more slowly.

It is always important to discuss about the procedure with the surgeon, prior to surgery, so that the patient is able to clear all doubts that he/she might have concerning the surgery.

The wisdom teeth, being positioned far behind all the other teeth, are difficult to clean while brushing and flossing. As a result, in spite of normal eruption and positioning, wisdom teeth are increasingly associated with problems such as decay and gum infections. About 50% of the population needs to have their wisdom teeth removed (made “wisdomless”) before the age of 40 years, in spite of not having them impacted, in many cases. As these teeth do not play a very important role in chewing, their removal does not compromise the chewing efficiency of individuals. On the contrary, removal of wisdom teeth have found to improve the chewing efficiency by eliminating problems in the gums behind the second molar teeth and facilitating better oral hygiene measures in the area which may not be otherwise possible. Hence, once removed, wisdom teeth are not generally replaced. It is extremely important for all individuals to get the status of their wisdom teeth assessed early by a dental surgeon, so that necessary treatment if indicated, may be instituted before much damage is done.

Before the operation

  1. Inform your dentist about any heart condition or any serious illness you have or had.
  2. Inform your dentist about any drug allergies you may have.
  3. Make arrangements in advance for a few days of medical leave.
  4. Have a good meal and brush your teeth.

After the operation

  1. A little oozing of blood is normal and should be expected. This can be stopped by biting on a piece of gauze placed on top of the wound, for about 20 – 30 minutes.
  2. Do not wash the mouth too vigorously or use your tongue to disturb the wound as these would dislodge the blood clot and cause further bleeding.
  3. Call your dentist if you think the wound is bleeding badly.
  4. You may place an ice-cold towel or ice-pack over your cheek to help reduce the swelling. Do not put warm compresses on the cheek as this will worsen the swelling.
  5. Take all the medicines given to you at the proper time. If antibiotics have been given to you, complete the whole course.
  6. Keep to a soft diet.
  7. Do not exercise vigorously or do heavy work.
  8. Do not smoke or drink alcohol.

After the first day of the operation, rinse your mouth gently after every meal to remove any trapped food at the wound. Continue to brush your teeth in the other parts of the mouth.

Dr. Vora's Dental Care We Treat We Care, Since 1975

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