Self-Setting Calcium Sulfate-Phosphate Bioactive Cement as "Barrier Graft" in Periodontal Defect Management: Preclinical Evaluation

Abstract

Alveolar bone loss associated with periodontitis is a common dental problem. Surgical debridement combined with the prevention of epithelial overgrowth by placing a ‘barrier membrane’ allows for bone regrowth. In cases of severe alveolar bone loss, grafting with a bioactive material is preferred alongside the barrier membrane. Various synthetic bone graft materials are currently in use. A calcium sulfate cement composition enriched with phosphate ions, developed for periodontal repair and designated by the acronym “CASPA,” has been designed. This self-setting, moldable, and biocompatible cement showed promising responses in previous in vitro studies. This report presents the preclinical evaluation of CASPA cement. Initially, the response of human periodontal ligament cells to this formulation was assessed through a direct contact cytotoxicity test and MTT assay in comparison with conventional calcium sulfate (gypsum-based) cement. Cell viability, adhesion, and morphology were also tested. The osteogenic induction potential of the cements was investigated through staining (Alizarin red and Von Kossa) and osteogenic marker expression. The periodontal defect healing potential of CASPA cement was evaluated in a rat maxillary alveolar bone defect model in comparison with conventional gypsum material. The newly developed bioactive calcium sulfate cement (CASPA) exhibited improved biological properties compared to conventional calcium sulfate (gypsum) cement. Biocompatibility was excellent both in vitro and in vivo in rats. CASPA showed a slower resorption rate that was on par with the rate of bone formation, ensuring site stability and complete defect healing. In clinical use, the conformal filling of the cement obviates the need for a barrier membrane. CASPA acts as a ‘barrier-graft’ and leads to better bone regeneration than conventional calcium sulfate.