Volumetric change of bony cavity and shrinkage speed after marsupialization for odontogenic keratocyst and unicystic ameloblastoma.

The aim of this study was to evaluate the efficacy of marsupialization treatment for odontogenic keratocyst (OKC) and unicystic ameloblastoma (UA) based on the three-dimensional volumetric change over time, and to determine the difference between OKC and UA in terms of the absolute volume reduction (AVR) and absolute shrinkage speed (ASS), and whether they are correlated with the preoperative volume, time after marsupialization (time between marsupialization and second treatment), and patient age. This was a retrospective cohort study with a sample size of 60 patients: 29 with OKC and 31 with UA. Pre- and post-marsupialization cone beam computed tomography images were analysed using Mimics software. The volume reduction and shrinkage speed were analysed and correlated with the preoperative volume, time after marsupialization, and demographic data. Descriptive univariable and multivariable statistics were computed; significance was set at P ≤ 0.05. The mean percentage volume reduction after marsupialization was 67.6 ± 9.6% for OKC and 63.3 ± 20.1% for UA. There was no significant difference in AVR or ASS between the OKC and UA groups. For OKC and UA, the preoperative volume (both P < 0.001) and time after marsupialization (P = 0.024 and P < 0.001, respectively) were associated with AVR. Moreover, for OKC and UA, the preoperative volume and time after marsupialization were also significantly associated with the ASS (all P < 0.001). For both lesions, patient age was not significantly related to AVR or ASS. Marsupialization appears to be a viable option to decrease the volume of OKC and UA. Age was found not to be associated with the volume reduction of either UA or OKC.