Bioactive glasses as bone substitutes for animal critical defects: A systematic review

Bioactive glasses (BGs) have garnered attention for their ability to bond with native bone tissue and exhibit osteoconductive properties. Despite studies investigating BGs for bone repair, results have been inconsistent, and an ideal formulation for regenerating critical defects has not been established. This systematic review aimed to analyze evidence regarding BG-based biomaterials for bone regeneration in animals with critical defects. The review followed PRISMA guidelines and was registered in PROSPERO (CRD42022325250). A literature search was conducted using PubMed, Web of Science, and Scopus, based on inclusion and exclusion criteria. The risk of bias was assessed using the SYRCLE RoB Tool for Animal Studies. Nine of the 1,467 identified studies were included. Most studies have indicated that bone defects created in rats and rabbits, and treated with BG-based biomaterials, show improved bone formation compared to untreated defects. Key parameters included bone volume, percentage of bone volume, bone mineral density, trabecular number, thickness, and separation. Although most studies indicate that BG-based biomaterials enhance bone formation in critical-sized defects compared to empty controls, study heterogeneity prevents the drawing of definitive conclusions. This review emphasizes the importance of standardized assessment methods to produce reliable research reports that provide robust evidence, ensuring accurate efficacy assessments and ultimately leading to more effective clinical interventions.