Radiographic observations on healing of critical size calvarial defects treated with polyvinyl alcohol-hydroxyapatite composite ceramic in rat models

Biodegradable composite bio-materials play a pivotal role in the healthcare and address many challenging issues. Bone refurbishment is a surgical procedure that repair segmental bone loss that are extremely complex which fail to heal properly. A novel bone graft substitute incorporating polyvinyl alcohol (PVA) and synthetic hydroxyapatite (HA) has been developed and is tested in vivo in rat calvarial defect models. The novel material is structurally and biomechanically similar to that of a natural bone. This study, focused on exploring the newer scaffold for bone regeneration which will positively eliminate the current issues in healing bone defects treated with a variety of other bone grafts. Radiography was utilised to evaluate the healing potential of the graft material. An immediate postoperative dorsoventral view of the skull was taken at day zero and subsequent radiographs were taken periodically at second, fourth, eighth and twelfth weeks. Immediate post operative radiograph revealed the radiolucent nature of the graft material. Throughout the healing process, it was observed that the graft remained in position and was intact. By eighth week, signs of progressive degradation of the graft material and bone regeneration could be seen. The test material was found to be completely integrated with the host bone by 12 weeks. It could be concluded that the test graft material successfully accelerated bone regeneration, and the PVA-HA composite could be used as an alternative to the available conventional bone grafts.