Effect of Alginate Coatings on Hydroxyapatite/β-Tricalcium Phosphate Scaffold Behavior

Chronic oral and maxillofacial diseases are frequently associated with progressive alveolar bone loss, leading to impaired structural integrity of the jaw and increased risk of implant failure, microbial colonization, and microfracture formation. Ceramic scaffolds such as those made of hydroxyapatite (HA) and β-tricalcium phosphate (β-TCP) have attracted considerable attention because of their controlled resorption properties and the promotion of rapid new vital bone formation. The aim of this research is to enhance the performance of scaffolds composed of HA and β-TCP used for guided bone tissue regeneration in oral surgery. HA/β-TCP scaffolds were loaded with simvastatin (SIMV) and coated with multiple layers of alginate (ALG). The proposed strategy was designed to achieve a local and prolonged drug release while simultaneously improving mechanical properties. The scaffolds were characterized in terms of porosity, water absorption, in vitro degradation, in vitro bioactivity, and SIMV release. In addition, microscale mechanical properties were evaluated using Brillouin microscopy before and after the coating process. Cytocompatibility was further evaluated by using murine macrophages as an in vitro cellular model. The results demonstrated that ALG coatings significantly modulated SIMV release, promoting a delayed drug release. Moreover, ALG deposition improved the micromechanical properties of the scaffolds, conferring a dual structure analogous to those of bone tissue. These findings indicate that ALG-coated SIMV-loaded HA/β-TCP scaffolds represent a promising multifunctional platform for the medical field.