3D Printing Technology and Its Diverse Applications

H. B. Muralidhara, Soumitra Banerjee, H. B. Muralidhara, Soumitra Banerjee

• Publisher: Apple Academic Press
• Year: 2021
• ISBN:
  9781000344240
• Edition: 1
• Topic: Design
• Subtopic: Design industriale

This new volume explores the exciting and diverse applications of three-dimensional printing in a variety of industries, including food processing, environmental sciences, biotechnology, medical devices, energy storage, civil engineering, the textile and fashion industry, and more. It describes the various 3D printing methods, the commonly used materials, and the pros and cons. It also presents an overview of the historical development and modern-day trends in additive manufacturing, as well as an exploration of the prospects of 3D printing technology in promoting academic education.

CHAPTER 9 Empowering Advances in Medical Devices with 3D-Printing Technology

KASHMA RAI* and UMA ULLAS PRADHAN

Center for Incubation, Innovation, Research & Consultancy (CIIRC), Jyothy Institute of Technology, Tataguni, Bengaluru 560082, Karnataka, India

*Corresponding author. E-mail: [email protected]

ABSTRACT

The need for individualized personal care has well-positioned three-dimensional (3D) printing in the health-care industry and the medical applications are expanding rapidly. It is one of the emerging technological frontiers, revolutionizing the medical devices industry by fast-tracking the designing phase, enabling new devices to reach the market faster. Current and potential medical applications of 3D printing include customized implants and prostheses, tissue and organ fabrication, surgical instrumentation, drug delivery and testing systems, and tumor models to understand cancer growth. The benefits include lowering cost for customized applications and easier access for low-income communities and low-resource settings. It is improving patient outcome and quality of life. However, there are also limitations such as regulatory concerns.

The promising 3D-printing technology is still in the emerging stage and with improving resolutions of the printed features, its potential is boundless. Here an overview of the advantages of 3D printing is presented for medical devices compared to traditional manufacturing techniques. The future potential and direction for medical applications is discussed along with key challenges.

9.1 INTRODUCTION

Three-dimensional printing (3DP) is an additive manufacturing (AM) technique for fabricating 3D objects using raw materials such as metals, ceramics, biodegradable materials, polymers, and biomaterials. This is in contrast to the typical ink printers that create two-dimensional (2D) objects. Earlier subtractive manufacturing was widely used in medicine. However, the advent of 3DP fabrication has created a paradigm shift toward rapid customized prototyping using AM.¹ The 3D structure is formed by adding materials layer-wise. Initial applications in healthcare were creating prototypes and surgical tools for surgical planning.² However, advances in the field has enabled features such as repeatability, accuracy, and ability to print complex structure using a wide array of materials. The ability to print biocompatible materials has evolved into fabrication of permanent hip implants. Printing materials, which are biocompatible, biodegradable, and absorbable, have found application in bone scaffold. Biomaterials such as cells for printing are being explored for drug-testing models and tissue constructs.

The 3DP technique, where customization can be easily achieved by editing the computer-aided design (CAD) files, is revolutionizing the health-care sector and has transformed ideas from proof-of-concept stage to innumerable real-world medical applications.^3–8 3DP growth is also boosted by the reducing cost of computational processing power of heavy CAD files. The expiration of key 3DP technology patents is leading to more competition and innovation.

AM is still emerging and evolving for various applications in health-care, but already well-harnessed for several other applications.

9.2 3D PRINTING IN HEALTHCARE

The future of the global health-care market is steering toward personalized treatment and 3DP is well positioned for this endeavor and can aid in patient-specific treatment or mass customization. It is a relatively new manufacturing technique for bespoke health-care applications and is envisaged to disrupt different health-care domains such as tissue engineering, pharmaceutical industry, anatomical models, and medical devices.

9.2.1 TISSUE ENGINEERING

3DP has garnered attention for printing biological cells and complex scaffolds, aiding in tissue and organ regeneration.^9,10 Cells and biomaterials can be integrated together and printed layer by layer to recreate tissue-like structure. Engineering tissues through 3DP techniques known as 3D bioprinting is in a nascent stage, and extensive multidisciplinary research is essential to fabricate 3D bioprinted tissues, as clinically viable alternatives for tissue and organ transplants. This technique is predicted to play a pivotal part in translational research of regenerative medicine.^10,11 Bioprinted 3DP technology has boundless potential applications in different medical areas.¹² Repair and graft of skin tissue is being actively pursued for wound healing.¹³

However, one of the biggest scientific challenges is building the vascular network, to supply nutrients and carry away waste from the tissues.¹⁰ Active research is ongoing to overcome this challenge by using innovative 3DP techniques.¹⁴ 3D bioprinting is also being pursued for tissue printing in laboratory settings to carry out drug development research. In vitro development of heterogenous structures, mimicking tissues, and organs could replace preclinical trial stage of animal testing altogether.¹⁵

9.2.2 PHARMACEUTICAL INDUSTRY

3DP is positioned to play a vital role in pharmaceutical industry especially for drug dosage forms.¹⁶ Dosage form is defined as the methods by which drugs are dispensed into the human body and can be classified depending on the physical form or the way of dispensing. Based on the physical form of drugs, they can be classified as solid, semisolid, and liquid dosage forms. Based on the mode of dispensing, they can be classified as oral, topical, parenteral, vaginal, rectal, inhaled, ophthalmic, and otic dosage forms. Conventionally, drugs are mass produced with standard formulations. However, they can be personalized using 3DP techniques to cater to individual needs of dosage, form factor, and delivery to the site of action.

Drug delivery release rate can be varied by fabricating different geometries of dosage forms.¹⁷ Targeted drug delivery for specific regions¹⁸ is also facilitated by 3DP fabrication technique. Drug discovery, design, and development is a capital-intensive process. 3DP has potential applications here to mitigate the cost.¹⁹ The drug failure rates are higher during the clinical development phase. It has been estimated that about 13.8% of drug development programs move from Phase 1 clinical trial phase to approval.²⁰ The high costs of inventing new drugs can be alleviated by using the rapid prototyping of 3DP to fabricate a small batch of formulations with flexible dosages. This enables early identification of successful formulations and drugs with requisite bioavailability.

Also, different doses can be synthesized along with easy-to-swallow form factors enabling easy ingestion for certain groups such as pediatric²¹ and geriatric demographic, who may face swallowing incompetence. Thus, 3DP enables design and development of drugs for individual requirements, and 3DP integrated into drug manufacturing can address most problems associated with the intake of drugs.

Spritam^® is the first 3D-printed drug approved by the Food and Drug Administration (FDA) in 2015, to treat epilepsy. Aprecia’s proprietary technology is used here to create a 3D-printed porous formulation to deliver high dosage of quickly disintegrating drug.²²

9.2.3 ANATOMICAL MODELS FOR TEACHING, PLANNING, AND PRACTICING

Anatomical models are utilized for different purposes and depending on the application, they are regulated as medical devices. They are used for teaching, training, and research not pertaining to any specific treatment. They are used as visualization models for surgical planning. 3D-printed anatomical models are now extensively used for preoperation planning by surgeons. It is a useful tool for the surgeons to train their support staff. The technology enables prototypes of patient-specific pathologies for patient education and consent. These models enable the patients to understand their medical condition better and the medical intervention required to treat it.

The medical models actively used during surgery for surgery rehearsal and reference need to be sterilizable and regulated as a medical device. Complex anatomy like the brain is hard to visualize using 2D radiographs. Any errors during surgery can be fatal or damaging. 3D-printed anatomical models are aiding the surgeons to study, practice, and plan the surgery better by tactile feedback and visualization of the models.^23–25

Using anatomical models for teaching, planning, and practicing is an efficient use o...