Dermoid Cyst

Dermoid Cyst
Etiology • Cystic degeneration of entrapped epithelium within the midline
fusion zone between the first and second branchial arches • Alternative etiology relates to in utero traumatic epithelial
implantation into floor of mouth area
Clinical Presentation • Slowly enlarging, usually asymptomatic, sublingual or floor-of-
mouth mass • May present as a soft and compressible paramedian swelling or
deformity • Overlying mucosa/skin is thinned, but is otherwise unremarkable • May have doughy consistency because of sebum and/or keratin
in cystic cavity
Microscopic Findings • Epithelial lining (stratified squamous) • Cyst contents may include keratin debris, hair follicles/hair,
and sebaceous and sweat glands. • Rarely find gastric mucosal characteristics present in cyst lining
Diagnosis • Aspiration may yield cellular debris, sebum, keratin, mucus • Histologic demonstration of hair follicles, sebaceous glands,

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

Dental Lamina Cyst (Bohn’s Nodules; Gingival Cyst of Newborn)

Etiology • Cystic degeneration of residual dental lamina/odontogenic
epithelium • Found in over 80% of newborns
Clinical Presentation • Small (1–2 mm), usually multiple, yellow-white nodules over
the alveolar crest in neonates •