Most electrospun scaffolds for bone tissue engineering typically use hydroxyapatite (HA) or beta tricalcium phosphate (β-TCP). However, the biological activity of these crystalline compounds can be limited due to their low solubility. Therefore, amorphous calcium phosphate (ACP) may be an alternative in bone repair scaffolds. This study analyzes the morphology, porosity, mechanical strength, and surface chemistry of electrospun scaffolds composed of polylactic acid and collagen integrated with hydroxyapatite (MHAP) or amorphous calcium phosphate (MACP). In addition, the in vitro biocompatibility, osteogenic differentiation, and growth factor production associated with bone repair using human Wharton’s jelly-derived mesenchymal stem cells (hWJ-MSCs) are evaluated. The results show that the electrospun MHAP and MACP scaffolds exhibit a fibrous morphology with interconnected pores. Both scaffolds exhibit favorable biocompatibility and stimulate the proliferation and osteogenesis of hWJ-MSCs. However, cell adhesion and osteocalcin production are greater in the MACP scaffold compared to the MHAP scaffold. In addition, the MACP scaffold shows significant production of bone-repair-related growth factors such as transforming growth factor-beta 1 (TGF-β1), providing a solid basis for its use in bone tissue engineering.

Bone repair via endochondral ossification is a complex process for the critical size reparation of bone defects. Tissue engineering strategies are being developed as alternative treatments to autografts or allografts. Most approaches to bone regeneration involve the use of calcium composites. However, exploring calcium-free alternatives in endochondral bone repair has emerged as a promising way to contribute to bone healing. By analyzing researches from the last ten years, this review identifies the potential benefits of such alternatives compared to traditional calcium-based approaches. Understanding the impact of calcium-free alternatives on endochondral bone repair can have profound implications for orthopedic and regenerative medicine. This review evaluates the efficacy of calcium-free alternatives in endochondral bone repair through in vivo trials. The findings may guide future research to develop innovative strategies to improve endochondral bone repair without relying on calcium. Exploring alternative approaches may lead to the discovery of novel therapies that improve bone healing outcomes.