PSI - Issue 83

Wong Kam Chee et al. / Procedia Structural Integrity 83 (2026) 14–27

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1. Introduction Traditionally, bone grafting has been used as a surgical technique to replace damaged bone with a substitute and allows new bone tissue to grow and fuse with the graft. However, it has limitations such as lack of suitable donors, disease transmission, and limited structural options [1], [2]. Consequently, biomedical implant materials have emerged as promising alternatives, offering customizable mechanical and biological properties that increases their values in orthopedic and dental applications. Despite the widespread use and benefits, biomedical implants face several clinical challenges that affect their effectiveness. The challenges included insufficient biocompatibility, limited ability to simulate bone regeneration, and inadequate long-term mechanical and biological stability under complex pathological environments. Additional clinical priority of biomedical implant is to minimize inflammatory response and risk of infection while ensure rapid bone healing [3]. The design and optimization of these complex structures increase the dependent of finite element method (FEM). FEM is a numerical method that discretize a continuum into finite-sized elements and is widely employed to solve various engineering problems including thermal, mechanical, and electromagnetic analyses [4], [5]. FEM is applied to evaluate the interactions between individual structural components to identify the stress distribution, deformation behavior, and structural stability under different loading conditions [5]. Researchers have tended to shift to use numerical solutions in solving engineering problems for the past two decades [6]. It offers a faster and more economical alternative to experimental methods, providing valuable insights that are often inaccessible through experimental approach [7], [8]. It also allows the isolation and evaluation of individual factors such as particle size, volume fraction, and matrix properties to understand composite behavior and phase transformation under various conditions [8]. The advancement of AM technology has outperformed conventional manufacturing methods [9], [10] by allowing the modelling of internal design geometry, known as the microstructure of the part produced [11], [12]. This technology has made the fabrication of customized implants, prosthetics, and live tissues that are specified to a patient possible [13]. The flexibility of AM which allows complex and intricate geometries is the main reason for its application in medical engineering soon after its development [14]. AM techniques aim to imitate bone tissue characteristics such as physical properties, mechanical properties, chemical properties and biological properties [15]. However, to advance this sector, it is crucial to develop innovative functional biomaterials and bio-inks that match or exceed the biological characteristics of human tissues in terms of shape retention, printing accuracy, and cell culture capabilities [13]. Due to the rapid transition between research developments and industrial applications, AM has attracted much attention from the scientific community and different industrial sectors in the past decade [16]. .Various 3D printing methods such as laser-based and extrusion-based methods are used to fabricate biomaterials [13]. 3D-printed metals are important biomaterials in the orthopedics, surgical tools and dentistry sectors thanks to the improvement of AM. It will expand towards more areas such as biodegradable implants and bioelectronics [17]. The fundamental properties of an orthopedic implant are biocompatibility, which is suitable for cell growth and non toxic, mechanically suitable for supporting loads and minimizing stress shielding, and highly porous for bone regeneration and ingrowth [18]. As one of the factors that causes stress shielding, material elastic modulus plays an important role in implant material selection. Higher material elastic modulus indicates a larger portion of the load is carried by the implant, which leads to stress shielding. Metallic biomaterials provides mechanical properties that more closely match the natural bone while potentially reduce adverse biological reactions and long-term complications associated with conventional metal implants [19]. The advancement of AM technology has made the fabrication of TPMS lattice structures possible. TPMS is a lattice subclass of metamaterials that are highly manufacturable and are useful in many sectors such as energy, acoustic absorption, medical engineering, robotics, etc. [20]. It is a structure with first-order and second-order continuity, and each point in the structure is zero mean curvature. Unlike conventional strut-based and skeletal based lattice structures, TPMS has a relatively large specific surface area and excellent surface connectivity, which presents smooth connecting surfaces [21]. The high specific surface area of TPMS structure is beneficial for cell adhesion, migration, proliferation, and nutrient transport in the fabrication of porous orthopedic implants [22]. This is important as a good scaffold provides mechanical support and converts cancer cells' growth factors into defects that stimulate bone tissue regeneration [23].