The effects of marsupialization on bone regeneration adjacent to keratocystic odontogenic tumors, and the mechanisms involved.

Bone resorption in the jaws is one of the most severe complications of keratocystic odontogenic tumors (KCOTs), and can be treated by either enucleation or marsupialization. However, the effects of marsupialization on bone regeneration adjacent to KCOTs, and the mechanisms involved, are still unclear. In this study, samples of 27 KCOTs were collected (20 before marsupialization and 7 after marsupialization) to detect the expression of bone regeneration-related molecules adjacent to KCOTs by immunohistochemistry and real-time quantitative polymerase chain reaction (qPCR). The results showed that bone formation was significantly enhanced in the KCOT capsule wall adjacent to bone after marsupialization, as demonstrated by alkaline phosphatase activity assay and immunostaining for bone morphogenetic protein. Moreover, immunohistochemistry revealed that osteoprotegerin (OPG) was up-regulated in the KCOT capsule wall adjacent to bone after marsupialization, while receptor activator of nuclear factor-κB ligand (RANKL) was down-regulated. Real-time qPCR also demonstrated increased expression of OPG after marsupialization, accompanied by a decrease in the expression of osteoclastogenesis-related molecules such as cathepsin K, matrix metalloproteinase-9, NFATc1, RANK and RANKL. This study provides further evidence that marsupialization may promote bone regeneration adjacent to KCOTs partially through regulation of the OPG/RANK/RANKL signaling pathway.