Inflammation-Modified Odontogenic Keratocyst Mimicking an Inflammatory Cyst: A Clinically Silent Case.

Odontogenic keratocyst (OKC) is a developmental odontogenic cyst with distinctive histopathological features and a recognized potential for recurrence. However, secondary inflammation may significantly alter or obscure its classical histopathological features, resulting in diagnostic overlap with inflammatory odontogenic cysts. A 40-year-old male patient presented with an incidentally detected, well-defined radiolucent lesion in the left posterior mandible associated with an impacted third molar. The lesion remained asymptomatic for approximately 11 years. Radiographic findings initially suggested a dentigerous cyst. Surgical management consisted of extraction of the impacted tooth followed by complete enucleation of the lesion. Histopathological examination revealed a non-keratinized stratified squamous epithelial lining with prominent inflammatory infiltrate and numerous cholesterol clefts. The cystic contents lacked typical keratinaceous material and appeared as a creamy cystic fluid. Despite the absence of classical keratinization, the diagnosis of inflammation-modified OKC was supported by preserved architectural features, including epithelial fragility and detachment, daughter (satellite) cysts or focal microcystic formations, odontogenic epithelial islands, and focal dystrophic calcification. Inflammatory modification may obscure the classical histopathological features of OKC and create significant diagnostic overlap with inflammatory odontogenic cysts. The absence or attenuation of keratinization does not exclude the diagnosis of OKC when preserved architectural clues remain identifiable within the cyst wall. Careful evaluation of preserved architectural features, combined with clinicopathologic correlation, is essential for accurate diagnosis, appropriate management, and structured long-term follow-up.