Evaluation of locally manufactured patient-specific custom made implants for cranial defects using a silicone mould

The study of CAD (computer aided design) modeling, design and manufacturing techniques has undergone a rapid growth over the past decades. In medicine, this development mainly concerned the dental and maxillofacial sectors. Significant progress has also been made in orthopedics with pre-operative CAD simulations, printing of bone models and production of patient-specific instruments. However, the traditional procedure that formulates the surgical plan based exclusively on two-dimensional images and interventions performed without the aid of specific instruments for the patient and is currently the most used surgical technique. The production of custom-made tools for the patient, in fact, is often expensive and its use is limited to a few hospitals. The purpose of this study is to show an innovative and cost-effective procedure aimed at prototyping a custom-made surgical guide for address the cubitus varus deformity on a pediatric patient. The cutting guides were obtained through an additive manufacturing process that starts from the 3D digital model of the patient’s bone and allows to design specific models using Creo Parametric. The result is a tool that adheres perfectly to the patient’s bone and guides the surgeon during the osteotomy procedure. The low cost of the methodology described makes it worth noticing by any health institution.

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Early Outcomes of Patient-Specific Modular Cones for Substitution of Methaphysial and Diaphysial Bone Defects in Revision Knee Arthroplasty

Traumatology and Orthopedics of Russia ◽

10.21823/2311-2905-2019-25-2-9-18 ◽

2019 ◽

Vol 25 (2) ◽

pp. 9-18 ◽

Cited By ~ 1

Author(s):

A. A. Cherny ◽

A. N. Kovalenko ◽

S. S. Bilyk ◽

A. O. Denisov ◽

A. V. Kazemirskiy ◽

...

Keyword(s):

Three Dimensional ◽

Scoring Systems ◽

Bone Defects ◽

Patient Specific ◽

Implant Fixation ◽

Diaphyseal Bone ◽

Custom Made ◽

The Stability ◽

Valid Solution

The aim of this study was the assessment of early outcomes of patient-specific three-dimensional titanium cones with specified porosity parameters to compensate for extensive metaphysical-diaphyseal bone defects in RTKA.Materials and Methods. Since 2017 till 2019 30 patient-specific titanium cones (12 femoral and 18 tibial) implanted during 26 RTKAS. Clinical outcomes evaluated using KSS, WOMAC and fjS-12 scoring systems on average 10 (2–18) months after surgery. At the same time the stability of implant fixation analyzed using frontal, lateral and axial knee roentgenograms.Results. During all procedures there were no technical difficulties in positioning and implantation of custom-made titanium cones. At the time of preparation of the publication, none of the patients had indications for further surgical intervention, as well as intra- and postoperative complications. Six months after surgery all scores improved significantly: KSS from 23 (2–42, SD 19.96) to 66.5 (62–78, SD 7.68), WOMAC from 59 (56–96, SD 28.31) to 32.25 (19–46, SD 11.76), the index FJS-12 was 29.16 points (0–68.75, SD 30.19). The average scores continued to improve up to 18 months: KSS — 97.5 (88–108, SD 9.14), WOMAC — 16.5 (9–24, SD 6.45), FJS-12 — 45.85 (25–75, SD 22.03). No radiolucent lines were noticed during this period of observation.Conclusion. The original additive technology of designing and producing patient-specific titanium cones for compensation of extensive metaphyseal-diaphyseal bone defects in RTKA is a valid solution at least in the short term. A longer follow-up period is required to assess its medium-and long-term reliability compared to existing alternative surgical solutions.

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Innovative Design Methodology for Patient-Specific Short Femoral Stems

Materials ◽

10.3390/ma15020442 ◽

2022 ◽

Vol 15 (2) ◽

pp. 442

Author(s):

William Solórzano-Requejo ◽

Carlos Ojeda ◽

Andrés Díaz Lantada

Keyword(s):

Computer Aided Design ◽

Design Methodology ◽

Patient Specific ◽

Bone Stock ◽

Innovative Design ◽

Hip Prostheses ◽

Custom Made ◽

In Silico Studies ◽

Femoral Stems ◽

Short Stems

The biomechanical performance of hip prostheses is often suboptimal, which leads to problems such as strain shielding, bone resorption and implant loosening, affecting the long-term viability of these implants for articular repair. Different studies have highlighted the interest of short stems for preserving bone stock and minimizing shielding, hence providing an alternative to conventional hip prostheses with long stems. Such short stems are especially valuable for younger patients, as they may require additional surgical interventions and replacements in the future, for which the preservation of bone stock is fundamental. Arguably, enhanced results may be achieved by combining the benefits of short stems with the possibilities of personalization, which are now empowered by a wise combination of medical images, computer-aided design and engineering resources and automated manufacturing tools. In this study, an innovative design methodology for custom-made short femoral stems is presented. The design process is enhanced through a novel app employing elliptical adjustment for the quasi-automated CAD modeling of personalized short femoral stems. The proposed methodology is validated by completely developing two personalized short femoral stems, which are evaluated by combining in silico studies (finite element method (FEM) simulations), for quantifying their biomechanical performance, and rapid prototyping, for evaluating implantability.

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A patient-specific guide for optimizing custom-made glenoid implantation in cases of severe glenoid defects: an in vitro study

Journal of Shoulder and Elbow Surgery ◽

10.1016/j.jse.2015.09.034 ◽

2016 ◽

Vol 25 (5) ◽

pp. 837-845 ◽

Cited By ~ 17

Author(s):

Koen Eraly ◽

Danny Stoffelen ◽

Jos Vander Sloten ◽

Ilse Jonkers ◽

Philippe Debeer

Keyword(s):

In Vitro Study ◽

Vitro Study ◽

Patient Specific ◽

Custom Made

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Use of Three-dimensional Printing and Patient-matched Implant in Total Hip Arthroplasty – a Case Study

Ortopedia Traumatologia Rehabilitacja ◽

10.5604/01.3001.0013.2935 ◽

2019 ◽

Vol 21 (3) ◽

pp. 207-216 ◽

Cited By ~ 1

Author(s):

Piotr Sypień ◽

Paweł Łęgosz ◽

Paweł Małdyk

Keyword(s):

Total Hip Arthroplasty ◽

Hip Arthroplasty ◽

Three Dimensional ◽

Revision Arthroplasty ◽

Patient Specific ◽

Oral Antibiotic ◽

Precise Position ◽

Total Hip ◽

Custom Made ◽

History Of

We present a case report of a 70-year-old female patient with a history of right hip dysplasia and total hip arthroplasty complicated by chronic periprosthetic hipction. Failure of oral antibiotic treatment was an indication for implant removal. A computed tomography scan performed during qualification for reimplantation revealed massive bone defects in the pelvis. A three-dimensional printed patient-specific anatomical model of the pelvis helped to determine the precise position and cup size in preoperative planning and prepare a patient-matched acetabulum. The custom-made endoprosthesis was implanted during revision arthroplasty.

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Design Automation for Mass Customisation via Additive Manufacture: A Case Study on Continuous Positive Airway Pressure Mask

Volume 11A: 46th Design Automation Conference (DAC) ◽

10.1115/detc2020-22316 ◽

2020 ◽

Author(s):

Shiya Li ◽

Stylianos Ploumpis ◽

Stefanos Zafeiriou ◽

Connor Myant

Keyword(s):

Continuous Positive Airway Pressure ◽

Airway Pressure ◽

Large Scale ◽

Positive Airway Pressure ◽

Complete Removal ◽

Statistical Shape Model ◽

Patient Specific ◽

Additive Manufacture ◽

Custom Made

Abstract Additive Manufacturing (AM) has been identified as a key enabler for Mass Customization (MC) due to its negligible tooling cost associated with producing one-off items. This is especially valuable for the medical industry where the ability to create patient-specific products can greatly improve performance and comfort. However, the use of AM so far has only been limited to previously custom-made devices due to the prohibitive design costs associated with a knowledge-intensive and highly manual design process. The research community has often overlooked this area and as yet no study has shown a completely automated process that can reduce or even eliminate this design cost for existing mass-produced ergonomic products (e.g. respirators). This study investigates the methodology of developing a completely automated design pipeline through a case study on Continuous Positive Airway Pressure (CPAP) mask. Through a parametric design approach, a fully automated pipeline was constructed based on a large-scale statistical shape model “learnt” from 9,663 high-resolution facial scans. The pipeline accepts a single “in-the-wild” facial image as the only data input and produces a CAD model of CPAP mask in under a minute. The significant reduction in design time, ease of data acquisition and the complete removal of a manual CAD modelling process can make AM more accessible for CPAP masks manufacturers. The same workflow can potentially be employed to construct automation pipelines for other types of wearables, therefore encouraging the adoption of AM for MC of a wider selection of products.

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Qualification of Customised Medical Implants Produced by Ti6Al4V(ELI) Additive Manufacturing

MATEC Web of Conferences ◽

10.1051/matecconf/202032103012 ◽

2020 ◽

Vol 321 ◽

pp. 03012

Author(s):

W B du Preez ◽

G J Booysen

Keyword(s):

Additive Manufacturing ◽

Quality Management ◽

Management System ◽

Quality Management System ◽

Titanium Implants ◽

International Standards ◽

Patient Specific ◽

Medical Implants ◽

Design Development ◽

Custom Made

Although many cases of medical implants produced through additive manufacturing (AM) in Ti6Al4V have been reported in literature, most of these processes had not been qualified. To enable certification and commercialisation of medical implants and devices an ISO 13485:2016 quality management system was successfully implemented in the Centre for Rapid Prototyping and Manufacturing (CRPM) at the Central University of Technology, Free State in South Africa. This certification covers qualification of both design, development and production of patient specific custom made titanium implants, as well as preoperative models, jigs and cutting guides in nylon by means of AM and supports commercialisation. With this quality management system as framework for ensuring the reliability and repeatability of the AM performed at the CRPM, the generation of data to validate the individual processes in the AM process chain was pursued. Sufficient research data has been produced and published to prove that medical implants produced through AM can fully comply with the international standards for material, physical, chemical and mechanical properties. In this paper the research performed towards the qualification of AM of Ti6Al4V medical implants is discussed. Examples are given of internationally leading work on utilising these implants in maxillofacial and orthopaedic surgeries.

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3D Bioprinted Cardiac Tissues and Devices for Tissue Maturation

Cells Tissues Organs ◽

10.1159/000512792 ◽

2021 ◽

pp. 1-14

Author(s):

Veronika Sedlakova ◽

Christopher McTiernan ◽

David Cortes ◽

Erik J. Suuronen ◽

Emilio I. Alarcon

Keyword(s):

3D Printing ◽

Tissue Repair ◽

Surgical Planning ◽

Cardiac Tissue ◽

Treatment Options ◽

Cardiac Regeneration ◽

Patient Specific ◽

Cardiac Tissues ◽

Cardiovascular Tissue ◽

Custom Made

Cardiovascular diseases are the leading cause of mortality worldwide. Given the limited endogenous regenerative capabilities of cardiac tissue, patient-specific anatomy, challenges in treatment options, and shortage of donor tissues for transplantation, there is an urgent need for novel approaches in cardiac tissue repair. 3D bioprinting is a technology based on additive manufacturing which allows for the design of precisely controlled and spatially organized structures, which could possibly lead to solutions in cardiac tissue repair. In this review, we describe the basic morphological and physiological specifics of the heart and cardiac tissues and introduce the readers to the fundamental principles underlying 3D printing technology and some of the materials/approaches which have been used to date for cardiac repair. By summarizing recent progress in 3D printing of cardiac tissue and valves with respect to the key features of cardiovascular tissue (such as contractility, conductivity, and vascularization), we highlight how 3D printing can facilitate surgical planning and provide custom-fit implants and properties that match those from the native heart. Finally, we also discuss the suitability of this technology in the design and fabrication of custom-made devices intended for the maturation of the cardiac tissue, a process that has been shown to increase the viability of implants. Altogether this review shows that 3D printing and bioprinting are versatile and highly modulative technologies with wide applications in cardiac regeneration and beyond.

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3DP materials and methods for orthopedic, dental and maxillofacial implants: a brief comparative report

Journal of 3D Printing in Medicine ◽

10.2217/3dp-2018-0020 ◽

2019 ◽

Vol 3 (3) ◽

pp. 127-134 ◽

Cited By ~ 1

Author(s):

Mohammed Sahal ◽

Mu Tao Chen ◽

Shruti Sharma ◽

Sidharth Sukumaran Nair ◽

Vaishakh Gopalakrishnan Nair

Keyword(s):

Complex Geometry ◽

Current Approach ◽

Patient Specific ◽

Skeletal Tissue ◽

Academic Paper ◽

Standard Procedures ◽

Custom Made ◽

Specific Complex ◽

Potential Benefits ◽

Manufacturing Techniques

The current approach of modifying standardized prosthetics for orthopedic, dental and maxillofacial implants made from conventional manufacturing techniques have been found inconvenient to customize for specific cases as the complex geometry of the skeletal tissue varies appreciably from patient to patient [ 1 , 2 ]. These standard procedures justly demand patient-specific, complex-shaped, custom-made implants be reliably delivered in minimal time. In this specific regard, 3DP implants are extensively researched [ 3 ]. A significant number of research outcomes sufficiently emphasize the desirable superior shape conformity and the short delivery time provided by the custom-made 3DP implants compared over conventional implants. These potential benefits facilitated by the novel 3DP technology can be adequately explained by the inherent ability of various modern 3DP disciplines to manufacture complex shaped implants by efficiently converting any patient-specific x-ray or CT scans into STL files. In this academic paper, we comparatively review the methods and materials utilized for specific 3DP implants.

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Modern Applications of 3D Printing: The Case of an Artificial Ear Splint Model

Methods and Protocols ◽

10.3390/mps4030054 ◽

2021 ◽

Vol 4 (3) ◽

pp. 54

Author(s):

Athanasios Argyropoulos ◽

Pantelis N. Botsaris

Keyword(s):

3D Printing ◽

Three Dimensional ◽

Shape Preservation ◽

Patient Specific ◽

Fused Deposition Modelling ◽

Comprehensive Overview ◽

Protruding Ears ◽

Fused Deposition ◽

Custom Made ◽

Wide Range

Three-dimensional (3D) printing is a leading manufacturing technique in the medical field. The constantly improving quality of 3D printers has revolutionized the approach to new challenges in medicine for a wide range of applications including otoplasty, medical devices, and tissue engineering. The aim of this study is to provide a comprehensive overview of an artificial ear splint model applied to the human auricle for the treatment of stick-out protruding ears. The deformity of stick-out protruding ears remains a significant challenge, where the complex and distinctive shape preservation are key factors. To address this challenge, we have developed a protocol that involves photogrammetry techniques, reverse engineering technologies, a smart prototype design, and 3D printing processes. Specifically, we fabricated a 3D printed ear splint model via fused deposition modelling (FDM) technology by testing two materials, a thermoplastic polyester elastomer material (Z-Flex) and polycaprolactone (PCL 100). Our strategy affords a custom-made and patient-specific artificial ear aligner with mechanical properties that ensures sufficient preservation of the auricular shape by applying a force on the helix and antihelix and enables the ears to pin back to the head.

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