Biochemical and Physicomechanical Cues of Biomaterials Guide Osteogenic Differentiation of Mesenchymal Stem Cells.

Bone regeneration remains a significant clinical challenge, particularly for large or critical-sized defects caused by trauma, disease, or congenital abnormalities. Mesenchymal stem cells (MSCs) have emerged as a promising cell source for bone tissue engineering, with their osteogenic differentiation playing a crucial role in bone repair. Biomaterials serve as scaffolds that facilitate MSC-mediated bone regeneration by providing structural support and mimicking the extracellular matrix (ECM). This review explores recent advancements in biomaterials designed to promote MSC osteogenesis through two primary approaches: biochemical and physicomechanical stimuli. Therapeutic agent-loaded scaffolds, incorporating growth factors, small molecules, gene materials, peptides, proteins, and extracellular vesicles (EVs), have been extensively studied for their ability to enhance osteogenic differentiation. However, concerns regarding toxicity, off-target effects, and regulatory limitations have led to increasing interest in biomaterials that utilize physicomechanical cues such as stiffness, viscoelasticity, topography, porosity, and dynamic forces (shear stress, compression, vibration) as alternative or complementary strategies. Furthermore, the synergistic effects of multiple physicomechanical cues are being explored to regulate MSC behavior for promoting bone regeneration. This review discusses current challenges, emerging trends, and future directions in the development of next-generation biomaterials that integrate biochemical and physicomechanical approaches for clinical applications in bone repair and regeneration.