Analysis on the guided bone augmentation in the rat calvarium using a microfocus computerized tomography analysis

Objectives. Guided bone augmentation (GBA) in its most challenging form is the creation of new bone through the guidance of bone cells to an area beyond the original outer skeletal envelope. We used a microfocus computerized tomography (R_mCT) system to examine bone augmentation beyond the skeletal envelope in the rat calvarium. Study design. The calvarium was exposed and critical-size 5-mm defects were prepared bilaterally. Two resin caps were placed with or without hydroxyapatite (HA), and images of bone augmentation within the resin cap were obtained using R_mCT. Results. The experimental site showed bone regeneration beyond the skeletal envelope. Bone continuity was observed between the defect edge and HA. In contrast, no new bone formation was observed beyond the skeletal envelope at the control site. The bone volume increased significantly at the experimental site compared with the control site in a time-dependent manner. Conclusions. The R_mCT system enabled the continuous observation of guided bone augmentation with graft materials in rat calvarium. (Oral Surg Oral Med Oral Pathol Oral Radiol Endod 2009;107:e42-e48)