Dentigerous Cyst: Classification, Imaging, Symptoms & Treatment

Posted on Jan 25, 2026 in Dentistry

Problem: Classify and Explain Dentigerous Cyst

Solution

Classification of Cysts

Cysts are pathological cavities, often filled with fluid or semi-solid material, and lined by epithelium. In the oral and maxillofacial region, they are primarily classified based on their origin.

1. Odontogenic Cysts (Tooth-Forming Origin)

Odontogenic cysts are derived from remnants of the epithelial tissues involved in tooth development (odontogenesis).

  1. Developmental Cysts: Arise from remnants of the epithelial tissues involved in tooth development.
    • Dentigerous (Follicular) Cyst: Surrounds the crown of an unerupted tooth.
    • Odontogenic Keratocyst (OKC): Known for aggressive behavior and high recurrence rate. It has been classified by some authorities as a benign neoplasm, keratocystic odontogenic tumor (KCOT), but is often discussed clinically with cysts.
    • Lateral Periodontal Cyst: Occurs along the lateral root surface of an erupted tooth.
    • Gingival Cyst: Arises from rests of dental lamina in the soft tissues of the gingiva.
    • Calcifying Odontogenic Cyst (Gorlin Cyst): A rare lesion that contains characteristic “ghost cells”; considered by some to behave like a benign neoplasm.
  2. Inflammatory Cysts: Result from an inflammatory process, typically initiated by pulp necrosis in a non-vital tooth.
    • Radicular (Periapical) Cyst: The most common odontogenic cyst, located at the apex of a non-vital tooth.
    • Residual Cyst: A radicular cyst that remains in the jaw after the causative tooth has been extracted.
    • Paradental Cyst: An inflammatory cyst located on the side of a partially erupted tooth, most commonly a mandibular third molar.

2. Non-Odontogenic Cysts (Fissural or Inclusion Origin)

These arise from epithelial remnants entrapped during the fusion of embryonic processes of the face and jaws.

  • Nasopalatine Duct (Incisive Canal) Cyst: The most common non-odontogenic cyst, located in the midline of the anterior maxilla.
  • Nasolabial Cyst: A rare soft tissue cyst occurring in the nasolabial fold area, inferior to the ala of the nose.

3. Pseudocysts (Not Lined by Epithelium)

These are bone cavities that are not lined by epithelium and are therefore not true cysts.

  • Traumatic (Simple) Bone Cyst: An empty or fluid-filled cavity within the bone, thought to be related to trauma.
  • Aneurysmal Bone Cyst: An expansile, blood-filled lesion containing fibrous tissue and giant cells.
  • Stafne Bone Defect (Static Bone Cavity): A developmental depression on the lingual aspect of the mandible, typically containing salivary gland tissue.

Dentigerous Cyst

A dentigerous cyst, also known as a follicular cyst, is a developmental odontogenic cyst that encloses the crown of an unerupted or impacted tooth and attaches to the tooth’s neck at the cementoenamel junction (CEJ).

Pathogenesis

The cyst forms from the accumulation of fluid between the reduced enamel epithelium (the epithelial layer covering the crown after enamel formation is complete) and the tooth crown. Pressure exerted by a potentially erupting tooth may obstruct venous outflow, leading to fluid transudation and cyst formation.

Clinical Features

  • Prevalence: It is the second most common odontogenic cyst after the radicular (periapical) cyst.
  • Location: Most commonly associated with impacted mandibular third molars, followed by maxillary canines, maxillary third molars, and mandibular second premolars.
  • Symptoms: Small cysts are typically asymptomatic and are often discovered incidentally on routine radiographs. Large cysts can cause significant, painless bony expansion, facial asymmetry, and displacement or resorption of adjacent teeth. Secondary infection can lead to pain and swelling.

Radiographic Features

A dentigerous cyst appears as a well-defined, unilocular (single-chambered) radiolucency with a distinct, sclerotic (corticated) border. The key diagnostic feature is its attachment to the CEJ of an unerupted tooth, with the radiolucent space enclosing the crown. A pericoronal space greater than 3 mm is considered suggestive of a dentigerous cyst.

Histopathology

The cyst is lined by a thin, non-keratinized stratified squamous epithelium, typically 2–4 cell layers thick. The underlying connective tissue wall is composed of fibrous tissue. In an uninflamed state, the epithelial-connective tissue interface is flat. If inflamed, the epithelial lining may show proliferation, and the connective tissue wall will contain chronic inflammatory cells.

Treatment and Prognosis

  • Enucleation: The standard treatment involves complete surgical removal of the cyst lining along with extraction of the associated tooth.
  • Marsupialization: For very large cysts where enucleation poses a risk of jaw fracture or damage to vital structures, marsupialization is performed. This involves creating a surgical window into the cyst, decompressing it, and allowing it to shrink over time. The tooth may be allowed to erupt or can be removed in a second, less invasive procedure.
  • Prognosis: The prognosis is excellent, and recurrence is rare following complete removal.
  • Complications: Although rare, the epithelial lining of a dentigerous cyst has the potential for neoplastic transformation into an ameloblastoma, squamous cell carcinoma, or mucoepidermoid carcinoma. Therefore, all excised tissue should be submitted for histopathological examination.