Biodegradation of Injectable Calcium Phosphate Bone Cements: A Dental Perspective

Abstract

The prevalence of tooth loss and edentulism is among the most ubiquitous diseases of human history. Dental implants have been widely used for the treatment of any type of edentulism. However, the absence of sufficient bone volume usually limits the placement of implants. Many techniques and materials have been developed to restore an adequate volume of bone for future implant placement, but the process of biode‐ gradation and replacement with new bone tissue is still under debate for all grafting materials. Among the available biomaterials, calcium phosphates (CaP) have been under the spot light for their advantages such as the ease of production and lack of disease transfer. The preparation of the material in two phases allowed self-hardening and subsequent space maintenance where it applied. This was of critical importance in load-bearing implants and joint prosthesis where rapid and strong healing is re‐ quired. The injectability also allowed a better handling and manipulation in compro‐ mised areas such as the oral cavity. A novel form of injectable calcium phosphate cement (iCaP) with two distinct formulations was tested on dog tibiae. Healing and ossifica‐ tion at 4 and 12 weeks were assessed by histologic and histomorphometric analysis. No adverse reactions or negative consequences were noted. Mean new bone formation was 22.12 (SD, 15.68), 18.62 (SD, 13.11), and 9.56 (SD, 11.11)% in the groups 1, 2, and the control, respectively. Statistically, significant higher new bone formation was evident in the groups 1 and 2 as compared to the control group (p < 0.01). However, these differences were no more discernable after 12 weeks of healing. The results of the present investigation showed excellent in vivo biocompatibility but insufficient biodegrada‐ tion of the iCaP in the center of the defect area. Further attempts are required to expedite the biodegradation of the iCaP