Bone Regeneration Capabilities of Scaffolds Containing Chitosan and Nanometric Hydroxyapatite-Systematic Review Based on In Vivo Examinations.

In this systematic review, the authors aimed to investigate the state of knowledge on in vivo evaluations of chitosan and nanometric hydroxyapatite (nanohydroxyapatite, nHAp) scaffolds for bone-tissue regeneration. In March 2024, an electronic search was systematically conducted across the PubMed, Cochrane, and Web of Science databases using the keywords (hydroxyapatite) AND (chitosan) AND (scaffold) AND (biomimetic). Methodologically, the systematic review followed the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) protocol to the letter. Initially, a total of 375 studies were screened, and 164 duplicates were removed. A further 188 articles were excluded because they did not correspond to the predefined topics, and an additional 3 articles were eliminated due to the inability to obtain the full text. The final compilation included 20 studies. All publications indicated a potential beneficial effect of the scaffolds in in vivo bone defect repair. A beneficial effect of hydroxyapatite as a scaffold component was observed in 16 studies, including greater mechanical resistance, cellular differentiation, and enhanced bone damage regeneration. The addition of chitosan and apatite ceramics, which combined the strengths of both materials, had the potential to become a useful bone-tissue engineering material.