Most people have three molars on each of the four corners inside the mouth. The third molar is known as the wisdom tooth. The wisdom tooth usually erupts in a person during their late teens or in their early twenties (most commonly between 18-25 years);though it is also common to find cases outside the above mentioned age frame.
Since this teeth erupts later than all others at an age when a person is comparatively more mature, hence the term ‘wisdom tooth’. It is not necessary that every human being will have all four wisdom teeth. Some may even have none erupted above the jaw-line. Surveys have found that 25% of the people lack one or more wisdom teeth.
In some people, more than four wisdom teeth are seen which is rare. Wisdom tooth are considered vestigial now since it was useful in grinding plant tissues in prehistoric times in the stone ages when man used to survive on cellulose rich leaves and plant foods.
Times have changed and the eating habits have changed too; and probably our jaw sizes have reduced relatively. A dentist can help you to find the position and alignment of your wisdom tooth with the help of an X ray. A periodic check is required to help your dentist to find out if any problems might crop up in future.
Wisdom teeth impaction problems
If there is not enough space in one’s jaw line, the wisdom tooth will not be able to erupt up onto its required position. In dental terminology, it is known as impacted tooth. An impaction may happen also when the path of eruption is blocked or obstructed by another tooth or an improper angulation of the tooth. The different types of wisdom teeth impactions are listed below:
- Mesial impaction: Tooth angled towards the front of the mouth
- Distal impaction: Tooth angled towards the rear of the mouth
- Horizontal impaction: Tooth lying on its side.
- Soft tissue impaction: The crown of the tooth has penetrated through the bone but has not been able to erupt out of the gum line
- Hard tissue impaction: The tooth is encased within the bone tissue either partially or fully. These problems arise usually due to a lack of space or also may be due to a bigger size of the tooth.
Why wisdom tooth impaction occurs
A simple answer would be the inadequate space within the jawbone on the backside of the 2nd molar. The reason for the lack of space is not clear, but there is certainly a correlation between large tooth size and wisdom teeth impaction. This impaction is also seen in patients who exhibit tooth crowding in general.
Around 70% of people have atleast one of their wisdom teeth impacted. This number is significant. Some researchers have proposed an interesting theory. They suggest that in ancient times(stone age), humans used their teeth roughly and ate harsher food, which caused the length of the teeth-set to reduce which made more jaw bone space – enough for 4 well erupted healthy wisdom teeth.
However in the modern area, humans eat softer food with better cooking methodologies and hence the jawbone space isn’t the same and this could be a possible explanation as to why wisdom tooth impaction happens.
When extraction becomes necessary?
Certain dental conditions make extraction pertinent. Some of them are briefly described below.
It is a condition caused by the bacterial infection of the tissue surrounding the outer shell of the tooth. Just when the wisdom tooth begins to erupt and show through the gum tissue, bacteria might enter into the area. The chance of bacteria entering and causing damage is higher if the tooth is impacted as the impaction could place the wisdom tooth in this permanent vulnerable position.
This becomes safe harbor for bacteria as it is difficult to clean the surrounding areas of the impacted wisdom teeth due to its peculiar positioning. With time this infection spreads to the entire tissue surrounding the wisdom tooth. Extraction becomes important in this situation.
Tooth decay & Gum disease:
Wisdom teeth, impacted or not receive less attention during daily brushing and as such are susceptible to tooth decay and gum diseases. While smaller cavities can be filled up, larger cavities and cavities in inaccessible areas make extraction an easier and safer solution.
Cysts and tumors:
Their occurrence is rare but possibility of tumors and cysts in the tissue surrounding an impacted wisdom tooth is a possibility and one that the dentist will check for using an Xray. Regular checkups to rule out cysts and tumors are recommended if the decision not to extract an impacted wisdom tooth has been made.
Damage to neighboring teeth:
Sometimes an impacted wisdom tooth in its efforts to erupt can put pressure on the 2nd molar which could cause structural instabilities of the 2nd molar. If this is allowed to continue, it could lead to the unfortunate situation of having to extract both teeth. Hence early detection of this can save the molar by extracting the wisdom tooth.
Pain is what usually gets the patient to the dental clinic. The pain may be due to the wisdom tooth undergoing the process of eruption. The dentist may decide to allow this process take its natural course of action and control the pain with analgesics, but if the pain persists for extended duration due to incomplete eruption due to impaction, then it is best to extract the tooth to relieve pain.
Factors affecting extraction complexity
The position and shape of the wisdom tooth determines the complexity of the extraction. The more a wisdom tooth has erupted the easier it is to extract and quicker the healing process is. Bony impactions are tougher to treat than soft tissue impactions. Also, distal and horizontal impactions are harder to remove than mesial and vertical impactions.
Upper wisdom teeth usually have three roots and lower ones two. The roots of an impacted wisdom tooth may be of irregular curvature or shape and sometimes distorted, all of which will make for a difficult case. Some wisdom teeth have fused roots and this actually simplify the extraction process.
Wisdom tooth extractions don’t always have to be difficult, some cases are actually simple. For instance extraction of upper wisdom teeth with fused roots is a relatively simple procedure. The dentist will educate the patient about the complexity of the case after the pre-extraction examination.
Surgical extraction may be necessary in cases where the wisdom tooth is covered by gum tissue. In such cases, the dentist will have to make incisions on the covering gum and then proceed to extract the teeth. If the teeth is also covered by jaw-bone, then some bone tissue will also have to be removed.
If the wisdom teeth is in a awkward positioning(horizontal), then sectioning might be the only option. This is a process in which the dentist breaks the tooth via a smaller opening and then removes the tooth in pieces.
The extraction process sounds difficult and truth be told, it is somewhat involved for complicated cases, but a good dentist can make the procedure relatively comfortable with good experienced hands and potent oral/nitrous oxide sedation and anesthetics.
An infection or a delayed healing is noticed in some cases.Dry sockets(alveolar osteitis) is one of the possible complications and is known to occur when optimal blood clot fails to form in the extracted tooth socket or if the clot is dislodged after forming. This condition is more common with the extractions involving the lower wisdom tooth and causes delayed healing characterized by foul odour.
Pain is also usually experienced and can range from low to severe. About 5% of the wisdom tooth extraction cases exhibit these complications, but it is essentially a temporary and manageable condition. Certain pain relievers and medical dressings can help in healing the pain until healing occurs.
Another rare complication is a condition called paresthesia wherein the nerve that lies in close proximity with the wisdom tooth is bruised during the extraction process causing the tongue, lip or chin to numb. This condition is more common in people aged above 35 years when extraction of tooth is clinically considered to be more complicated. This is a temporary condition which can be reversed.
An extraction tends to be less complicated when the patient is younger than 35 because of lesser bone density. The medical history of the patient is looked into before finalizing the extraction as the healing process might be interrupted when certain medications are being used.
The inherent risks as in any surgical procedure exist in extraction of wisdom tooth too. Advanced medical techniques have reduced the complications to minimum. In some cases, the anatomical structure of the adjacent teeth and the mandibular nerves connected are at risk.