Abstract

Type III of dental gypsum waste is commonly discarded as medical waste despite containing high amounts of calcium-based minerals with potential for biomaterial synthesis. This study aimed to develop porous hydroxyapatite (HAp) scaffolds derived from dental gypsum waste and evaluate their physicochemical characteristics and degradation behavior for bone tissue engineering applications. Hydroxyapatite was synthesized through a hydrothermal reaction using dental gypsum waste as the calcium precursor and diammonium hydrogen phosphate as the phosphate source. Porous scaffolds were fabricated using sucrose as a porogen with Dental Gypsum Hydroxyapatite (DGHAp) type III : sucrose ratios of 35:65, 45:55, and 55:45, followed by sintering at 950–1150°C. FTIR analysis confirmed the formation of characteristic phosphate and hydroxyl groups of hydroxyapatites, along with carbonate groups indicating carbonated hydroxyapatite formation. SEM observations revealed interconnected porous structures in all scaffold groups. Higher sucrose content increased pore size and porosity, whereas higher DGHAp content produced denser scaffold structures. Degradation testing demonstrated that higher porosity increased scaffold degradation, while higher sintering temperatures reduced degradation due to increased crystallinity and densification. Among all groups, DGHAp 45% showed the most balanced characteristics regarding porosity and structural stability. These findings demonstrate the potential of dental gypsum waste as a sustainable precursor for porous hydroxyapatite scaffolds with controllable degradation behavior.