Dental Cyst

Dental-Cyst

Dental Cyst

A dental or jaw cyst is a closed sac formed by a distinct membrane or lining in the jaw bone. It usually contains fluid and causes erosion of nearby bone tissue. A true cyst will remain permanent until removed. A cyst appears as a black cavity in a x-ray film or screen.

Amongst the more common cysts found in the jaw bones are:

  • Dentigerous cyst, which is associated with buried tooth
  • Radicular cyst, which is associated with infection at the root tips of a tooth
  • Primordial cyst, which is formed from residual cells from developing tooth buds.
  • Keratocyst, a special category that has great propensity to recur following treatment. As such, this lesion has been re-classified as “Keratocystic Odontogenic Tumour”.
  • Unicystic ameloblastoma, an odontogenic tumour which is locally invasive.

Diagnosis

Before a specific treatment can be prescribed, diagnosis must be made by biopsy. A part of the cyst is surgically removed and examined under the microscope to identify the cell types. Occasionally, specialised tests may be needed. Most jaw cysts are benign. However, some may be locally invasive or cancerous.

Treatment

The main treatment methods are:

Marsupialisation

  • The cyst is surgically “burst” opened. As the cystic membrane merges with the oral mucosa, the bone defect refills. A time interval of up to a year may be needed and only the benign cyst-type is suitable for this treatment modality.

Enucleation

  • The lining of the cyst is separated from the bone and surrounding tissues. The resulting bony defect may be treated with burring, cryotherapy, laser or chemicals such as Carnoy’s solution.

Resection

  • A segment of the bone is surgically removed along with the cyst. The discontinuity defect is reconstructed with bone graft harvested from another site such as the hip bone or leg (femur). Titanium bone plates and screws are used to fixate the bone.

Decompression

  • Occasionally, a large cyst is “marsupialised” first to allow it to shrink before being “enucleated”.
Dentigerous cyst in left lower jaw
Complete healing after”enucleation”