This article outlines the selection criteria for choosing an implant material for biomedical devices in orthopedic, dental, soft-tissue, and cardiovascular applications. It details the development of various implants, such as metallic, ceramic, and polymeric implants. The article discusses specific problems associated with implant manufacturing processes and the consequent compromises in the properties of functionally graded implants. It describes the manufacturing of the functionally-graded hip implant by using the LENS process. The article reviews four different types of tissue responses to the biomaterial. It discusses the testing methods of implant failure, such as in vitro and in vivo assessment of tissue compatibility.

One of the most frequently cited advantages of ceramics in dentistry relates to aesthetics, and the same applies for dental implants. Zirconia has emerged as the material of choice for nonmetal implants. This article introduces the reader to zirconia as an implant material, its properties, manufacturing processes, and the particular surface modifications and treatments that have rendered its surfaces biologically compatible with peri-implant soft and hard tissues.

This article focuses on ceramics, glasses, glass-ceramics, and their derivatives, that is, inorganic-organic hybrids, in the forms of solid or porous bodies, oxide layers/coatings, and particles with sizes ranging from nanometers to micrometers, or even millimetres. These include inert crystalline ceramics, porous ceramics, calcium phosphate ceramics, and bioactive glasses. The article discusses the compositions of ceramics and carbon-base implant materials, and examines their differences in processing and structure. It describes the chemical and microstructural basis for their differences in physical properties, and relates the properties and hard-tissue response to particular clinical applications. The article also provides information on the glass or glass-ceramic particles used in cancer treatments.

In the field of medical device development and testing, the corrosion of metallic parts can lead to significant adverse effects on the biocompatibility of the device. This article describes the mechanisms of metal and alloy biocompatibility. It reviews the response of implant metals and particulate materials to corrosion. The effect of metal ions from an implanted device on the human body is also discussed. The article concludes with information on the possible cancer-causing effects of metallic biomaterials.

This article provides a summary of the biocompatibility or biological response of metals, ceramics, and polymers used in medical implants, along with their clinical issues. The polymers include ultrahigh-molecular-weight polyethylene, nonresorbable polymer, and resorbable polymers.

This article discusses the mechanisms of metal and alloy biocompatibility. It provides information on early testing and experience with metals in medical device applications. The article describes the response of implant and particulate materials to severe corrosion. It provides a description of metal binding and its effects on metabolic processes. Hypersensitive responses to metal ions are also reviewed. The article concludes with a discussion on the possible cancer-causing effects of metallic biomaterials.

This article focuses on the pneumatic extrusion-based system for biomaterials. It provides an overview of additive manufacturing (AM) processes, followed by sections covering steps and major approaches for the 3D bioprinting process. Then, the article discusses the types, processes, advantages, limitations, and applications of AM technology and extrusion-based approaches. Next, it provides information on the research on extrusion-based printing. Finally, the article provides a comparison of the extrusion-based approach with other approaches.

Piezoelectric jetting is a common form of additive manufacturing technology. With the development of material science and manufacturing devices, piezoelectric jetting of biomaterials has been applied to various fields including biosensors, tissue engineering, deoxyribonucleic acid (DNA) synthesis, and biorobots. This article discusses the processes involved in piezoelectric jetting of biosensors and biorobots and the applications of piezoelectric jetting for tissue engineering and producing DNA. In addition, it reviews the challenges and perspectives of piezoelectric jetting.

This article begins with a description of extrusion-based bioprinting for tissue scaffold fabrication. It also examines various extrusion-based bioprinting processes and related tissue scaffolding strategies, presents the selection criteria of various bioinks with various polymers and their printed scaffolds for applications in tissue engineering and regenerative medicines, and provides future research recommendations to address the shortcomings and issues found in current extrusion-based bioprinting processes.

This article commences with a description of the prosthetic devices and implants used for internal fixation. It describes the complications related to implants and provides a list of major standards for orthopedic implant materials. The article illustrates the body environment and its interactions with implants. The considerations for designing internal fixation devices are also described. The article analyzes failed internal fixation devices by explaining the failures of implants and prosthetic devices due to implant deficiencies, mechanical or biomechanical conditions, and degradation. Finally, the article discusses the fatigue properties of implant materials and the fractures of total hip joint prostheses.

Due to its layer-by-layer process, 3D printing enables the formation of complex geometries using multiple materials. Three-dimensional printing for bone tissue engineering is called bioprinting and refers to the use of material-transfer processes for patterning and assembling biologically relevant materials, molecules, cells, tissues, and biodegradable biomaterials with a prescribed organization to accomplish one or more biological functions. Currently, 3D bioprinting constructs can be classified into two categories: acellular and cellular. This article introduces and discusses these two approaches based on the suitable materials for these constructs and the fabrication processes used to manufacture them. The materials are grouped into polymers, metals, and hydrogels. The article also summarizes the commonly used 3D printing techniques for these materials, as well as cell types used for various applications. Lastly, current challenges in tissue engineering are discussed.

This article discusses the state of the art in the 3D bioprinting field. It examines the printability of protein-based biopolymers and provides key printing parameters, along with a brief description of the main current 3D bioprinting approaches. The article presents some studies investigating 3D bioprinting of naturally derived proteins for the production of structurally and functionally biomimetic scaffolds, which create a microenvironment for cells resembling that of the native tissues. It describes key structural proteins processed in the form of hydrogels, such as collagen, silk, fibrin, and others such as elastin, decellularized matrix, and Matrigel (Corning), which are used as biomaterials.

Bioprinting has been advancing in the field of tissue engineering as the process for fabricating scaffolds, making use of additive manufacturing technologies. In situ bioprinting (also termed intraoperative bioprinting) is a promising solution to address the limitations of conventional bioprinting approaches. This article discusses the main approaches and technologies for in situ bioprinting. It provides a brief overview of the bioprinting pipeline, highlighting possible solutions to improve currently used approaches. Additionally, case studies of in situ bioprinting are provided and in situ bioprinting future perspectives are discussed.

This article discusses alginate/gelatin-based bioinks in 3D bioprinting applications, providing a summary of the most relevant previous work in the field. It presents advanced compositions to enhance functionality and/or optimize hydrogels for 3D bioprinting. The article discusses advanced printing techniques for alginate/gelatin-based bioinks.

The field of bioprinting is a subset of additive manufacturing (AM) that is rapidly expanding to meet the needs of regenerative medicine and tissue engineering. Bioprinting encompasses a broad spectrum of issues, from cell expansion and novel bioink development to cell/stem cell printing, from organoid-based tissue organization to bioprinting of human-scale tissue structures, and from building cell/tissue/organ-on-a-chip to biomanufacturing of multicellular engineered living systems. This article focuses on two challenges regarding bioprinting: bioinks and crosslinking. It describes the methods for characterizing the performance of bioink formulations and the effectiveness of crosslinking strategies. The topics covered include modalities of bioprinting, characteristics of bioink, rheological properties of bioink sols, rheological measurements, mathematical models of bioink rheology, postfabrication polymer network mechanics, mechanical properties of crosslinked bioinks, and printability of bioinks. Finally, specific strategies used for crosslinking bioinks, as well as some emerging strategies to further improve bioinks and their crosslinking, are summarized.

Powder-bed fusion (PBF) is a group of additive manufacturing (AM) processes that includes selective laser sintering, selective laser melting, and electron beam melting. This article explains the processes and parameters of PBF systems that are used for biomedical applications. It also presents the desirable properties of biomedical devices and the advantages of using PBF systems for biomedical applications.

Three-dimensional plotting of biomaterials (also known as bioprinting) has been a major milestone for scientists and engineers working in nanobiotechnology, nanoscience, and nanomedicine. It is typically classified into two major categories, depending on the plotting principle, as contact and noncontact techniques. This article focuses on the working principles of contact and noncontact printing methods along with their advantages, disadvantages, applications, and challenges. Contact printing methods include micro-plotter, pen printing, screen printing, nanoimprint printing, flexography printing, and gravure printing. Noncontact printing methods include extrusion printing, droplet printing, laser-based polymerization, and laser-based cell transfer. The wide variety of printable biomaterials, such as DNA, peptides, proteins, lipids, and cells, also are discussed.

Stereolithographic (STL) additive manufacturing (AM) can be used to fabricate practical components. This article discusses the processes involved in STL-AM of biological scaffolds, providing information on bioscaffold processing, cavity arrangements, and microlattice distributions. Within the last topic, the sub-topic of scaffold modulation is discussed.

Vat polymerization is a form of three-dimensional (3D) printing. Historically, it is the oldest additive manufacturing technique, with the development of stereolithography apparatus (SLA) by Charles Hull in 1986. This article outlines the various forms of vat polymerization techniques used for biomedical applications. Due to the complex nature of this printing process, many key print parameters and material properties need to be considered to ensure a successful print. These influential parameters are addressed throughout the article to inform the reader of the considerations that should be taken when using the vat polymerization technique. The article provides information on vat polymerization printer setup, the photo-cross-linking mechanism, and considerations using vat polymerization. In addition, it outlines and discusses the advancements of vat polymerization in the biomedical industry.