Dentigerous Cyst

Etiology • A developmental odontogenic cyst arising subsequent to sepa-
ration between dental follicle and the crown of an associated unerupted tooth
• Proliferation of reduced enamel epithelium lining the follicle, with fluid accumulation between epithelium and impacted tooth crown
• Alternatively, degeneration of the stellate reticulum component of the enamel organ occurs during odontogenesis.
Clinical Presentation • Most commonly involves frequently impacted teeth: mandibular third molars, followed by maxillary canines

• Usually noted during second and third decades • Asymptomatic; discovered on routine radiographic examination • Painless jaw/alveolar expansion may occur; cortex is thinned
and rarely perforated
Radiographic Findings • Well-defined radiolucency enclosing crown of unerupted tooth • Corticated/opaque margins unless infected • May produce root resorption of adjacent erupted teeth • Usually unilocular; less commonly multilocular
Diagnosis: Microscopic • Cysts without secondary inflammation
• Thin, cuboidal, nonkeratinized epithelial lining two cell layers thick with flat epithelial–connective tissue interface
• Loosely arranged collagen bundles, occasionally containing scattered odontogenic epithelial rests
• Cysts with secondary inflammation • Hyperplastic, nonkeratinized squamous epithelial lining
with epithelial ridge development • Variable chronic inflammatory cell infiltrate within
condensed collagen stroma

Differential Diagnosis: Radiographic • Odontogenic keratocyst • Ameloblastoma
Treatment • Cyst enucleation and extraction of associated tooth • Marsupialization prior to excision may be considered if the
cyst is very large.
Prognosis • Excellent • Possible complications
• Pathologic fracture with large lesions • Neoplastic transformation of epithelial lining
(ameloblastoma and, rarely, squamous cell carcinoma)