Dental Root Cysts
1. What is a root cyst?
A root cyst (periapical or radicular cyst) is a fluid-filled sac in the jawbone that usually develops from a decayed tooth whose pulp has died. Toxins from the dead pulp cause inflammation at the root tip; long-standing inflammation stimulates the epithelial rests of Malassez in the periodontal ligament to proliferate, and a cyst forms.
Cysts most often occur in the upper jaw, especially around the front teeth. The larger the cyst, the more bone is destroyed and the bigger the fluid-filled cavity; over time the bone becomes thin and fragile.
2. Signs and symptoms
A root cyst usually grows silently with almost no symptoms, so it is hard to notice on your own. Possible signs include:
- Tooth discolouration, especially of a tooth that has had decay or an injury.
- Swelling of the jaw: a large cyst makes the bone bulge and can change the shape of the face; it is often painless, so it is easily missed.
- How the swelling feels when pressed: firm at an early stage, but it may become soft and give way as the cyst grows.
- A baby tooth that does not fall out even though it is past the usual age (in children).
- Shifting teeth or bulging bone.
3. Is a root cyst dangerous?
- It destroys bone, may spread to the roots of neighbouring teeth and, without timely treatment, can lead to the loss of several teeth.
- It damages the tissues around the root tip, and the infection gradually spreads.
- It affects chewing and can distort the face.
4. Treatment
The dentist examines you and takes an X-ray or CT scan to assess the size of the cyst. Depending on the case, treatment may include root canal treatment of the affected tooth and surgical removal of the cyst — surgery is the definitive solution.