Publication:

Calvarial bone defect regeneration using beta-tricalcium phosphate: a translational research study in rat animal model

Background Guided bone regeneration (GBR) using osteoconductive graft materials has been used for osseous defect healing. The aim of this translational research study was to design and test a critical size calvarial defect (CSD) model in rats, to test GBR with beta-tricalcium phosphate (beta-TCP), using histology and micro computed tomography (micro-CT) assessment.

Methods Female Wistar albino rats (n=10) weighing 300 grams and aged 6-weeks were used and full thickness CSD were created in calvaria following exposure under general anesthesia. CSD were randomly divided into two groups for treatment, based on defect filling material: control group (no graft placed in defect; n=5); and beta-TCP group (defect grafted with beta-TCP; n=5). Both defects were covered with collagen membrane. After 8-weeks of healing the animals were sacrificed and calvarial specimens were subjected to micro-CT and histological assessment.

Results Based on micro-CT the new bone volume (NBV) was significantly higher in beta-TCP group (3.48±0.27 mm3; p<0.05), than control group (2.88±0.33 mm3). Similarly, new bone mineral density (NBMD) was significantly higher in beta-TCP group (0.426±0.018 g/mm3; p<0.01), than control group (0.243±0.015 g/mm3). Histology revealed greater new bone bridging the entire defect with interspersed graft particles in the beta-TCP group.

Conclusions Within the limitations of the present study, GBR of rat calvarial CSD with beta-TCP and collagen membrane, results in significantly higher NBV and NBMD, and is a reliable and reproducible translational research model.