Impacted wisdom teeth

Impacted wisdom teeth are third molars that fail to erupt fully into the mouth.

This condition occurs when a tooth is prevented from reaching its proper position. It can be caused by a physical barrier, such as adjacent teeth. It can also happen when a tooth is angled away from a vertical position. While completely unerupted teeth often cause no symptoms, they can still lead to medical issues. These include the development of cysts or neoplasms, which are growths like tumors.

The mechanism of impaction is often tied to the available space in the jaw. Because wisdom teeth are the last to erupt, they frequently run out of room. This may be due to genetic factors that dictate jaw and tooth size. Some research suggests that changes in human diets have played a role. For example, the move from hunter-gatherer lifestyles to farming and industrialization may have contributed. Studies show that animals fed on uncooked vegetables have larger jaws than those on soft, processed diets. This suggests that modern diets might result in smaller jaws that cannot accommodate all teeth.

Dentists classify impacted teeth using several specific factors. They look at the direction of the impaction, such as a mesioangular tilt, which is a forward tilt.

They also consider the depth of the tooth relative to the biting surface of other teeth. Another factor is how much of the tooth's crown extends through the bone or gum tissue. In U.S. dental schools, students learn the Pell and Gregory Classification. This system uses a horizontal "y" component and a vertical "x" component to describe the tooth's location.

These classifications help clinicians estimate the risks of infection and surgical complications.

Symptoms vary depending on whether the tooth communicates with the mouth. If a tooth is completely covered by bone or tissue, it may be asymptomatic. This means the person feels no pain, even if disease is present. However, if a tooth is partially erupted, food and bacteria can enter the space around it. This often leads to pericoronitis, which is inflammation around the crown of the tooth.

This condition causes localized pain, swelling, and bleeding in the tissue called the operculum. Other issues include caries, or tooth decay, and periodontal disease.

History shows that humans have been aware of wisdom teeth for millennia. Ancient thinkers like Plato and Hippocrates described them in their texts. Even Charles Darwin wrote about them in his scientific works.

However, routine management only became possible in the late 19th and early 20th centuries. This was due to the meeting of three important advancements: sterile technique, radiology, and anesthesia. These tools allowed doctors to see the teeth clearly and perform surgery with more control.

The decision to remove wisdom teeth involves complex medical considerations. Some practitioners prefer prophylactic extraction, which is preventative removal. This is often done during the middle to late teenage years. At this age, root development is incomplete, making the surgery easier with fewer complications.

However, recent decades have brought a controversy regarding this timing. Some health organizations now suggest only removing teeth that cause current issues. This avoids the cost and risk of unnecessary surgery. There is a debate between the risk of future disease and the risk of immediate surgery.

Surgery carries specific risks that depend on the difficulty of the extraction. If there is a high risk to the inferior alveolar nerve, a doctor might perform a coronectomy. In this procedure, only the crown of the tooth is removed, leaving the roots behind.

While this protects the nerve, the long-term risk is that chronic infection can persist in the remaining roots. Additionally, the prognosis for the second molar is affected by the patient's age. Research shows that the likelihood of bone loss after surgery increases in people aged 25 or older. This highlights why timing and careful diagnosis are so important in dental care.