Wisdom teeth, also known as third molars, are the last teeth to erupt in the mouth. They appear behind the second molars, with one wisdom tooth on each side of both the upper and lower jaws, totaling four wisdom teeth.
Wisdom teeth are often the most commonly missing and malformed teeth, which can make treatment challenging if they become infected. Let’s explore why wisdom tooth cavities develop and the available treatment options:
Why do you get a wisdom tooth cavity?
Wisdom teeth, being the last teeth to erupt in the mouth, often face challenges in plaque removal, especially if they erupt in an abnormal position due to limited space in the dental arch. This difficulty in cleaning can lead to cavities.
Partially impacted wisdom teeth are more susceptible to cavities because the gum tissue partially covering the tooth creates a pocket where food can get trapped. This can lead to gum inflammation (pericoronitis) and tooth decay.
Risks Associated with Wisdom Tooth Surgery
Post-extraction, patients may experience swelling, bleeding, limited mouth opening, and pain for 5-7 days. Research indicates that 48% of people develop a gum defect at the back of the second molar. There is also a risk of infection (1-4%) and dry socket (2-26%).
Nerve injury, particularly to the inferior alveolar or lingual nerve, is a potential risk during extraction. However, most nerve injuries are temporary, with recovery within six months. Permanent damage occurs in about 1% of cases.
If an X-ray (OPG) shows the inferior alveolar nerve close to the wisdom tooth, a CBCT scan (3D CT scan) may be requested to better assess the proximity. If the nerve is very close, a coronectomy (removal of the crown, leaving the root) may be considered.
Treatment of a wisdom tooth cavity
While cavities in other teeth are typically treated with fillings or root canal therapy, wisdom teeth require a different approach due to several challenges:
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Challenges during Wisdom Tooth Cavity Treatment
The wisdom tooth is treated a bit differently than the other teeth because of the following reasons.
- Wisdom teeth are hard to reach, especially in individuals with limited mouth opening.
- Wisdom teeth have complex and variable root anatomy.
- They often have Unfavorable, inappropriate angulation.
- The upper wisdom teeth are close to the sinus cavity, and the lower ones are near important nerves and blood vessels.
Filling a wisdom tooth cavity
Small to moderate-sized cavities in wisdom teeth can be filled with composite or amalgam fillings.
Tooth canal treatment of a wisdom tooth cavity
Root canal treatment is generally not recommended for wisdom teeth due to their complex root anatomy and remote location. Most dentists prefer extraction, as removing a wisdom tooth does not affect chewing efficiency if the first and second molars are healthy. However, if the first and second molars are compromised, a root canal may be considered for the wisdom tooth.
Extraction of a wisdom tooth
Extraction is often recommended if the cavity is deep or affecting the adjacent second molar. A tilted or malpositioned wisdom tooth causing periodontal problems or a cavity in the second molar is also a candidate for extraction. Preserving the second molar is crucial for effective chewing, and it can be treated with a filling or root canal therapy due to its simpler root anatomy and higher success rate.
Risks associated with wisdom tooth surgery
Post-extraction, patients may experience swelling, bleeding, limited mouth opening, and pain for 5-7 days. Research indicates that 48% of people develop a gum defect at the back of the second molar. There is also a risk of infection (1-4%) and dry socket (2-26%).
Nerve injury, particularly to the inferior alveolar or lingual nerve, is a potential risk during extraction. However, most nerve injuries are temporary, with recovery within six months. Permanent damage occurs in about 1% of cases.
If an X-ray (OPG) shows the inferior alveolar nerve close to the wisdom tooth, a CBCT scan (3D CT scan) may be requested to better assess the proximity. If the nerve is very close, a coronectomy (removal of the crown, leaving the root) may be considered.
Read more: 10 Signs of healthy gums
FAQs (discussing the common scenarios)
Is Every Tooth Cavity Caused by Decay?
Not every cavity on a tooth indicates decay. Sometimes, anatomical variations exist, and some teeth have deep fossae or indentations that resemble cavities. Wisdom teeth, located at the back of the mouth, can be difficult to visualize in the mirror or feel with the tongue.
Dentists are trained professionals who provide advice after examining your teeth and x-rays. If your dentist says there is no cavity, there is no need to worry. However, you can always seek a second opinion if you have concerns.
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What Happens if a Wisdom Tooth Moves into the Sinus Cavity?
Sinus perforation requires immediate attention. The displacement of the root into the sinus during extraction may cause pus, infection, and pain in the sinus. When a sinus gets perforated, a burst of air coming from sinus may occur. Such cases require professional consultation with a maxillofacial surgeon.
The roots of upper wisdom teeth may lie close to or within the sinus cavity. If the tooth is healthy, there is no need to worry about its roots in the sinus cavity. However, if the tooth is infected and broken, the infected root can lead to a sinus infection.
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Is there a temporary Material for Filling Decayed Wisdom Tooth Cavities at Home?
There is no suitable temporary material available at home to fill a decayed wisdom tooth. A filling requires the removal of decay because it contains viable bacteria that will continue to destroy the tooth if left in place. Sealing a tooth without removing decay can also lead to pus formation and swelling.
Can a Cavity on the Front Top of an Upper Left Wisdom Tooth Be Filled?
Yes, a small cavity in a wisdom tooth can be filled with a composite filling. Dental composite is a tooth-colored filling material that lasts for at least 5-7 years.
What is the treatment of a wisdom tooth cavity with no pain?
It is difficult to provide specific advice without examining the tooth and x-ray. However, the lack of pain suggests a small or moderately sized cavity (dentinal caries) that can be filled with a composite or amalgam filling. The best approach is to save the wisdom tooth as long as possible if the cavity is small and the tooth is not causing any major problems.
However, if an x-ray reveals potential future complications, an extraction may be considered. In such cases, it is best to discuss all possible treatment options and the best long-term approach with your dentist.
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Can a Wisdom Tooth Cause a Cavity in the Adjacent Tooth?
Yes, wisdom teeth can cause cavities in neighboring teeth. Often, the lack of space in the jaw causes wisdom teeth to erupt in a tilted or abnormal position, making it difficult to clean the space between the wisdom tooth and the rear (distal) surface of the second molar. This can result in cavities or periodontal problems in the second molar, necessitating the removal of the wisdom tooth to save the second molar.
Why Fill a Wisdom Tooth Cavity Before Removal?
There is generally no reason to fill a tooth before its removal. However, a dentist might initially underestimate the extent of decay in a wisdom tooth and recommend a filling. Upon drilling and removing the decay, the dentist may discover extensive decay that suggests the need for extraction. In such cases, the dentist may fill the tooth and recommend its removal at the next appointment. The cost of the filling is often adjusted with the extraction cost, so the patient is not charged extra.
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Will My Lower Wisdom Tooth Cause Problems After Extracting the Upper Wisdom Tooth?
Yes, there is a chance that the lower molar will over-erupt once the upper wisdom tooth on the same side is removed. Teeth are genetically programmed to erupt until they come into contact with teeth in the opposite arch. If the lower wisdom tooth does not make contact with the upper teeth, it may over-erupt and require extraction.
• Mild: 0.1-1.5mm of over-eruption
• Moderate: 1.6-3.5mm
• Severe: Exceeding 3.5mm
Depending on the degree of over-eruption, extraction or bite adjustment by trimming the chewing surface of the molar may be necessary. Delaying extraction of a third molar with no opposing tooth can lead to masticatory inefficiency and future joint problems (temporomandibular joint dysfunction).
How to Identify a Cavity in a Wisdom Tooth
Signs of a cavity include a black dot or hole in the tooth, pain or sensitivity, and bad breath from the rotting tooth. The presence of two or more of these symptoms often indicates a cavity. However, it is always best to consult your dentist for an accurate diagnosis.
Can I Get Cavities Filled After Wisdom Tooth Extraction?
Yes, you can get your cavities filled next week. Pain and swelling from wisdom tooth extractions typically settle in 7-10 days. A filling does not cause pain and swelling, so you can proceed with the wisdom teeth surgeries the day after the filling.
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Should I Remove or Fill a Cavity in My Wisdom Tooth?
Consult your dentist for an evaluation. It is generally best to save the wisdom tooth if possible. Small to moderate cavities can be filled with a composite filling, which can last for years with good oral hygiene. Root canal therapy is also an option for those with uncomplicated root canal anatomy. The decision to save or remove the tooth varies from person to person.
Can Wisdom Teeth Be Removed Without a Cavity?
Yes, wisdom teeth can be removed even if there is no cavity. Dentists may recommend removal in the following circumstances:
- A painful impacted wisdom tooth with frequent episodes of pericoronitis.
- An unfavorable position of the wisdom tooth.
- For orthodontic purposes, to create space if first molar distalization is anticipated.
The decision to remove a wisdom tooth varies from case to case and depends on the position of the third molar and the extent of damage caused by it