Comparing the characteristics of recurrent versus primary odontogenic keratocysts – A single center retrospective cohort study

The high recurrence rate of odontogenic keratocysts (OKC) entails a large number of follow-up interventions after primary surgery. This study aimed to compare recurrent with primary OKC in regard to recurrence rate, treatment modality, and radiographic and clinical findings.A single center retrospective cohort study with surgically treated OKC between 2012 and 2021 was conducted. The primary predictor was recurrence type of the lesion: primary (P-OKC), first recurrence (R1-OKC) and second recurrence (R2-OKC). The primary outcome variables were recurrence and time to recurrence.68 surgeries were identified. Recurrence was not significantly associated with recurrence type (p = 0.906) but with the method of surgery (p < 0.001). Marsupialized R1-OKC recurred earlier than marsupialized P-OKC. Diameter was significantly associated with recurrence type (p = 0.002). R1-OKC had a smaller median diameter than P-OKC and R2-OKC were smaller than R1-and P-OKC. P-OKC were associated with teeth in 79% of surgeries, R1-OKC in 61% and R2-OKC in 27% (p = 0.007). Postoperative numbness was present after 40% of surgeries and decreased to 15% at follow-up, independently of recurrence type.Time to recurrence may be shorter for recurrent marsupialized OKC. Recurrent OKC are smaller and less often associated with teeth. Postoperative numbness after OKC surgery has a good prognosis.