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,
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,
keratinizing cystic lining
Differential Diagnosis • Cellulitis of odontogenic origin • Sublingual sialadenitis • Ranula (superficial or deep/plunging)
Treatment • Intraoral surgical excision
Prognosis • Excellent