OVERVIEW

What are wisdom teeth?

Wisdom teeth refer to the third molars in the upper and lower jaws, also known as late teeth. They are located at the innermost part of the dental arch and are the most prone to impaction (impacted teeth are those that can only partially erupt or fail to erupt completely due to obstruction from adjacent teeth or bone)^[1].

Wisdom teeth typically emerge between the ages of 18 and 25 (though in many cases, they do not erupt and remain unseen in the mouth). Since people in this age range are nearing physical and psychological maturity, the emergence of these teeth is regarded as a symbol of wisdom^[2].

SYMPTOMS

What are the symptoms of impacted wisdom teeth?

When wisdom teeth are partially impacted or fail to fully erupt, the soft tissues around the gum-covered crown are prone to inflammation, often manifesting as:

• Swelling and pain in the gums around the wisdom teeth.
• Facial congestion and edema. Misaligned wisdom teeth can trap food debris between the crown and gums, leading to infection and subsequent swelling and pain in the surrounding soft tissues.
• If inflammation and pain spread to adjacent tissues, symptoms may include difficulty opening the mouth, pain when swallowing, and facial congestion and edema.
• Wisdom teeth growing toward the cheek may irritate the buccal mucosa, while those growing toward the tongue may cause a foreign body sensation.
• Severe cases may involve systemic discomfort, headache, fever, and loss of appetite.
• Inflammation may recur whenever immunity is weakened.

CAUSES

What is an impacted tooth?

An impacted tooth refers to a tooth that cannot fully or partially erupt due to obstruction by adjacent teeth, bone, or soft tissue, and will not erupt in the future.

Common impacted teeth include the third molars (upper and lower) and the upper canines. Broadly speaking, however, any tooth can become impacted.

Why do impacted teeth occur?

As humans evolve, the jawbones (the large bones housing the upper and lower teeth) degenerate faster than the reduction in the number of teeth, leaving insufficient space to accommodate all permanent teeth, resulting in impaction.

Why are wisdom teeth prone to impaction?

The growth of wisdom teeth is a normal physiological process. However, because they erupt later in life, by which time most other teeth have already developed, the space for wisdom teeth is often occupied, making eruption difficult and leading to impaction. If there is sufficient space for normal eruption, wisdom teeth will not become impacted^[2,3].

DIAGNOSIS

How are wisdom teeth diagnosed?

When wisdom teeth are completely impacted or erupt normally, they usually show no symptoms and can be clearly diagnosed through X-ray examination. If pain occurs due to pericoronitis, an oral examination combined with dental X-rays such as panoramic radiographs can confirm the diagnosis.

Is an X-ray necessary before wisdom tooth extraction?

Yes. The roots of mandibular wisdom teeth are closely related to the inferior alveolar nerve canal. X-rays can clearly reveal the number and shape of the wisdom tooth roots, as well as their positional relationship with adjacent teeth and the alveolar nerve canal. This helps dentists perform targeted extractions and facilitates the surgical procedure.

TREATMENT

Which department should I visit for wisdom teeth?

Dentistry, Oral and Maxillofacial Surgery.

Do wisdom teeth always need to be removed?

Not necessarily.

Not all wisdom teeth require extraction. A dentist can evaluate and make a decision based on various factors. Some wisdom teeth may be retained if they cause no symptoms, pathology, or impact on adjacent tissues or jaw movement. Others may need extraction if they exhibit symptoms, pathology, or negatively affect neighboring teeth, gums, bone, or jaw movement^[2].

Under what circumstances is wisdom tooth extraction recommended?

• Repeated pericoronitis caused by impacted mandibular wisdom teeth;
• Decay or forward tilting of impacted wisdom teeth leading to decay or damage in adjacent teeth;
• Misaligned wisdom teeth causing food impaction between them and neighboring teeth;
• Interference with orthodontic treatment or affecting its results;
• Potential cause of jaw movement issues (e.g., jaw joint pain, clicking sounds, or bite dysfunction);
• Suspected source of cysts, tumors, or neuralgia;
• Misaligned wisdom teeth repeatedly biting surrounding mucosa, causing ulcers or erosion.

To prevent these issues, asymptomatic wisdom teeth may also be extracted^[2].

When can wisdom teeth be retained?

• Wisdom teeth that erupt normally without causing inflammation or pain;
• Wisdom teeth that remain completely unerupted and asymptomatic;
• Missing or compromised adjacent teeth, where the wisdom tooth (if moderately tilted and structurally sound) can serve as a prosthetic support.

However, these cases may still be preventively extracted based on individual needs, especially for women, as tooth extraction is not recommended during pregnancy, leaving only symptomatic relief as an option if wisdom teeth flare up.

Should inflamed wisdom teeth be extracted only after the inflammation subsides?

Generally, extraction is not advised during acute inflammation. Symptoms like gum swelling, pus discharge, limited mouth opening, or systemic issues (fever, headache, infection) may worsen if extraction is performed. Delaying until inflammation resolves reduces risks like bacterial spread (e.g., endocarditis). Follow medical advice for anti-inflammatory treatment before extraction.

Is wisdom tooth extraction painful?

Local anesthesia ensures minimal pain during the procedure. Post-extraction pain (1–2 hours after anesthesia wears off) can be managed with prescribed painkillers or anti-inflammatory drugs.

Does wisdom tooth extraction require stitches?

It depends on the case. Fully erupted wisdom teeth with good visibility may not need gum incisions or stitches. Partially erupted or poorly visible teeth may require incisions and stitches, removed after 7 days. Mandibular extractions more often involve stitches than maxillary ones.

What if bleeding persists after wisdom tooth extraction?

Minor blood-tinged saliva within 24 hours is normal; avoid spitting. For significant bleeding, bite down on gauze/cotton over the extraction site. If bleeding continues, seek immediate medical attention.

Are medications needed after wisdom tooth extraction?

Not always. Antibiotics (e.g., amoxicillin, metronidazole) or painkillers may be prescribed based on trauma severity. For minor extractions, medication may be unnecessary^[4].

What complications may arise during wisdom tooth extraction?

• Root fracture: Likely with curved/multi-rooted teeth; removal depends on professional assessment.
• Gum injury: Tearing during extraction may require stitches.
• Adjacent tooth damage: Forceful removal of tilted teeth may harm neighboring teeth/dental work.
• Nerve injury: Risk of lip/tongue numbness from inferior alveolar/other nerve damage.
• Bone injury: Rare fractures/dislocations of jawbone or TMJ.
• Maxillary sinus perforation: Possible with upper wisdom teeth close to sinus lining.
• Postoperative bleeding: Due to trauma or inadequate hemostasis.
• Dry socket: Severe pain 3–5 days post-extraction from dislodged blood clot (osteomyelitis).

What post-extraction discomfort may occur, and how to manage it?

• Pain: Lasts 3–5 days; preventive painkillers may be advised for complex cases.
• Swelling: Peaks in 12–24 hours; cold compresses help.
• Trismus (jaw stiffness): Heat application reduces muscle spasms.
• Bleeding: Saliva mixed with blood may exaggerate perceived bleeding; bite gauze for 30 mins post-extraction.
• Infection: Follow antibiotic prescriptions if given.

Does wisdom tooth extraction affect intelligence?

No. Wisdom tooth nerves (from the inferior alveolar nerve) are terminal; no evidence links them to IQ.

Does wisdom tooth extraction slim the face?

No. Facial shape depends on jawbone, muscles, and fat. Extraction may cause temporary swelling, creating a false "slimmer face" illusion post-recovery^[2].

What’s the best age for wisdom tooth extraction?

18–22 years (ideally before 25). Younger patients heal faster with fewer complications. Delayed extraction increases difficulty, adjacent tissue damage, and risks^[2].

Can wisdom teeth be extracted during pregnancy or menstruation?

Avoid extraction in the first/third trimesters (risk of miscarriage/preterm birth). Menstruation increases bleeding/infection risks; postpone extraction^[2].

Can root canal treatment be done on painful wisdom teeth?

Not recommended due to limited access and positioning challenges.

What if a wisdom tooth is decayed?

Extraction is advised to prevent pulp damage and protect adjacent teeth/gums, as cleaning these teeth is often difficult.

DIET & LIFESTYLE

What precautions should be taken regarding diet and daily life after wisdom tooth extraction?

After wisdom tooth extraction, the doctor will place a cotton ball on the wound to aid clotting. The patient must bite down firmly on the cotton ball and should not remove it until half an hour later. Additionally, avoid repeatedly touching the wound with hands or the tongue to prevent infection.

Do not brush your teeth or rinse your mouth within 24 hours. After 24 hours, you may brush your teeth, but avoid vigorous rinsing to prevent dislodging the blood clot, which could lead to dry socket.

It is normal for saliva to contain traces of blood within the first 24 hours after extraction. Avoid sucking on the saliva; instead, swallow it gently. Seek immediate medical attention if excessive bleeding occurs.

Avoid eating for the first two hours after extraction. After two hours, you may consume lukewarm or cool liquid or semi-liquid foods. Refrain from strenuous physical activity^[2].

Does wisdom tooth extraction affect pregnancy planning?

No. Tooth extraction involves only local anesthesia, with minimal and low-concentration medication that wears off within a few hours, posing no adverse effects on pregnancy planning. During pregnancy, increased estrogen levels and reduced immunity may raise the risk of pericoronitis. However, X-rays and antibiotic treatments are unsuitable during pregnancy. Therefore, it is advisable to undergo a thorough dental examination before planning pregnancy and remove any wisdom teeth that have caused or may cause inflammation.

PREVENTION

How to prevent discomfort caused by wisdom teeth eruption?

Currently, there are no effective preventive measures, but regular dental check-ups, paying attention to dietary habits and lifestyle in daily life can have positive significance in preventing discomfort during the growth of wisdom teeth.