Application and evaluation of carbonate apatite granules for mandibular bone defect reconstruction after jawbone cyst enucleation–a retrospective case series

Purpose: To evaluate the effectiveness of CO₃Ap granules in the mandibular bone defects by using computed tomography (CT) images. Methods: This study was retrospective case series of mandibular bone defect reconstruction using CO₃Ap granules. Six patients with jawbone cysts treated by simultaneous grafting CO₃Ap granules after cyst enucleation were enrolled. Patients without grafting CO₃Ap granules were excluded. Mandibular bone height including buccolingual bone height, the change of perpendicular distance between the buccolingual line to the alveolar ridge, and the three-dimensional volume of remaining CO₃Ap granules were analyzed using CT images obtained at 3, 6, 12, 18, and 24 months postoperatively. Results: Postoperative CT images showed that cortical and cancellous bone-like structures were formed on the grafting area periphery and inside the defect, respectively, with gradual resorption of the CO₃Ap granules. Furthermore, there was no evidence of leaving bone defect even at the center of the lesion when the defect was successfully reconstructed by filling it with CO₃Ap granules. The percentage volume of remaining CO₃Ap granules to the volume at 3 months postoperatively were 76.1 ± 13.1%, 35.8 ± 22.5%, 25.0 ± 13.0%, and 9.9 ± 6.4% at 6, 12, 18, and 24 months postoperatively, and the volume reduction rate increased significantly within 12 months postoperatively. Conclusion: Grafting CO₃Ap granules after the enucleation of a jawbone cyst is a good reconstructive treatment option for postoperative prosthetic treatment because CO₃Ap granules are gradually replaced by new bone while preserving the contour of the mandibular bone. Clinical trial number: Not applicable.