Peripheral Odontogenic Keratocyst of the Gingiva: A Systematic Review of the Literature and Case Report.

Background/Objectives: Odontogenic keratocysts are benign cysts originating from remnants of the dental lamina, rarely showing peripheral (gingival) localization. In this study, we compiled data on the peripheral variant by reviewing the literature and presenting a new case to establish criteria for accurate differential diagnosis and treatment. Methods: A systematic literature review was conducted following the PRISMA flowchart, leading to the collection of existing data on peripheral odontogenic keratocyst. In addition, we present a new case of a 68-year-old female patient referred to our attention for an asymptomatic swelling of the mandible in the premolar area. Radiographic examination revealed a round radiolucency with well-defined borders located between teeth #4.3 and #4.4, surgically removed and diagnosed as a peripheral (gingival) keratocyst. Results: Including the herein described new case, 37 cases were reviewed from data literature showing occurrence in the mandible (43.2%) and maxilla (46%)-with 10.8% of cases not stated-, with an age range of 14-83 year old, recurrence rate of 12.5-13.6% (total recurrences/total cases) and median follow-up time of 19 months. Conclusions: Data from literature highlights the rarity of odontogenic keratocyst with peripheral (gingival) localization, which can be misleading for differential diagnosis, emphasizing the necessity of histopathological examination as the definitive diagnostic tool for all the cystic lesions of the jaws. The absence of pathognomonic clinical and radiological features, combined with the potential for extraosseous manifestation of odontogenic lesions with high recurrence rates, underscores the importance of complete excision to ensure proper healing and prevent recurrence of odontogenic keratocyst.