Four Wisdom Tooth Impactions and What They Mean
What are Wisdom Tooth Impactions?
When a wisdom tooth erupts through the gums and into the open it’s known as eruption. Impaction is where the third molars (wisdom teeth) erupt improperly. There are four types of impaction. Some of them mean you need wisdom teeth removal, whereas others are perfectly harmless. We’re going to go through each of the four impactions and determine whether they would warrant an extraction or not.![]() |
Lower mandibular third molar impaction Source: Lesion, CC-Zero, via Wikimedia Commons |
Many patients, and dentists alike, are quick to assume that impacted wisdom teeth automatically need removing, this is not always the case and each person should be thoroughly examined and x-rayed before this important decision is made.
Wisdom teeth removal is classed as surgery, and should therefore always be the last resort when it comes to treating the problem.
Mesial Impaction
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It most often leads to a partial eruption where only the back of the tooth pokes into the gums. In many cases, you can leave it without having it removed. Over time, it might erupt properly. Dentists normally place these impactions under inspection unless it’s clear it will never erupt.
Vertical Impaction
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If a vertically impacted wisdom tooth does need removing, it’s because it’s pushing against the underside of the molar in front or the bones at the back of the mouth. These are difficult to remove and often result in damage to the surrounding teeth and bone areas. It’s rare for a vertical impaction to be this serious, though.
Vertically impacted wisdom teeth can normally be extracted by your dentist using a local anaesthetic. IV sedation would only be required in the case of an extremely nervous patient.
Distal Impaction
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If it’s almost pointing towards 0 degrees, it will erupt as normal but will always have a slight incline. It will fit in the mouth and dentists will normally give it a year or two before they make a decision on whether they need to remove it.
Distal impactions which are towards a 90 degree angle will hit bone and probably won’t erupt fully. It’s usually up to the dentist as to whether they say the tooth needs removing or not.
Depending on the severity of this impaction, IV sedation or even general anaesthetic may be required to undergo the surgery.
Horizontal Impaction
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The difficulties presented by this impaction are the surgery and the fact the dentist can’t see it apart from with an x-ray. It takes a lot of skill to complete this type of wisdom tooth removal without causing trauma to the surrounding area.
As this kind of impaction could result in having to remove some bone, general anaesthetic or IV sedation is generally recommended. The patient should also be prescribed painkillers and a thorough after care plan to minimise discomfort and possible post-surgery complications.
Make sure you always use an experienced dental surgeon for this kind of procedure to minimise the damage caused to the surrounding area.
If wisdom teeth removal surgery has been recommended, you should be thoroughly informed of what will happen during the procedure. Don’t be afraid to ask questions, and if you don’t feel comfortable with your dental surgeon, remember you can always walk away and find another one!
Medical References
- MacGregor, A.J. The impacted lower wisdom tooth. Oxford University Press, 1985, ISBN 0192614053.
- Reinhard E. Friedrich, Carsten Ulbricht, The influence of wisdom tooth impaction on root formation, Annals of Anatomy - Anatomischer Anzeiger, Volume 185, Issue 5, October 2003, Pages 481-492, ISSN 0940-9602.
- Lennart Flygare, Anders Öhman. Preoperative imaging procedures for lower wisdom teeth removal. Clinical Oral Investigations, December 2008, Volume 12, Issue 4, pp 291-302.
- Arne Björk, Elli Jensen and Mogens Palling. Mandibular growth and third molar impaction. 1956, Vol. 14, No. 3 , Pages 231-272, doi: 10.3109/00016355609019762.