Concept and Evolution in 3-D Printing for Excellence in Healthcare.

Three-dimensional printing (3DP) has gained popularity among scientists and researchers in every field due to its potential to drastically reduce energy costs for the production of customised products by utilising less energy-intensive machines as well as minimising material waste. The 3D printing technology is an additive manufacturing approach that uses material layer-by-layer fabrication to produce the digitally specified 3D model. The use of 3D printing technology in the pharmaceutical sector has the potential to revolutionise research and development by providing a quick and easy means to manufacture personalised one-off batches, each with unique dosages, distinct substances, shapes, and sizes, as well as variable release rates. This overview addresses the concept of 3D printing, its evolution, and its operation, as well as the most popular types of 3D printing processes utilised in the health care industry. It also discusses the application of these cutting-edge technologies to the pharmaceutical industry, advancements in various medical fields and medical equipment, 3D bioprinting, the most recent initiatives to combat COVID-19, regulatory frameworks, and the major challenges that this technology currently faces. In addition, we attempt to provide some futuristic approaches to 3DP applications.

Antibacterial Effect and Therapy of Chronic Skin Defects Using the Composite Bioscaffold Polycaprolactone/GelitaSpon/Povidone-Iodine in Domestic Dogs.

Chronic wounds and the failure of conventional treatment are relatively common in veterinary medicine. Recently, there has been a growing interest in alternative therapeutic approaches and the utilization of biodegradable materials. Their potential application in wound therapy may offer a novel and more suitable option compared to conventional treatment methods. Biodegradable materials can be classified into two main categories: natural, synthetic, and a combination of both, which have the potential to have synergistically enhanced properties. In this study, four domestic dogs with clinical symptoms of chronic wounds were enrolled. These wounds underwent treatment utilizing a novel biodegradable composite material composed of gelatin sponge combined with two electrospun layers of polycaprolactone (PCL) along with polyvinylpyrrolidone (PVP) fibers containing povidone-iodine complex (PVP-I). The initial phase of the study was dedicated to evaluating the antibacterial properties of iodine against Staphylococcus aureus and Escherichia coli. On average, wound healing in domestic dogs took 22 days from the initial treatment, and iodine concentrations demonstrated a significant antibacterial effect against Escherichia coli and Staphylococcus aureus. Based on the favorable outcomes observed in wound management, we believe that the utilization of a blend of natural and synthetic biodegradable materials holds promise as an effective wound therapy option.

Dental Auto Transplantation Success Rate Increases by Utilizing 3D Replicas.

Dental autotransplantation is an effective alternative to conventional dental treatment, and it involves removing a tooth and repositioning it in a new position within the same patient. Although this procedure might pose more intraoperative challenges, it provides a great solution for replacing missing teeth or aiding difficult eruption in young patients. This prospective method is also advocated as a use of treatment for unrestorable teeth. The success rates of autotransplantation cases with and without replicas were compared in a retrospective analysis of the data. By reducing donor tooth manipulation and ensuring a proper fit and positioning in the recipient socket, replicas significantly increased success rates of the procedure. CBCT scans were used to collect data. Data exported to the Mimics system were then processed in order to achieve a model of the donor tooth. Additive manufacturing technology was used to create the replicas. Specialized biocompatible material was used. Details of the replantation site and the donor tooth requirements were described, as well as the step-by-step surgical technique. For the best results, variables, like patient selection, surgical technique, and long-term monitoring, were found to be essential. The study highlights the significance of dental professionals and biomedical engineering staff working together to develop standard operating procedures and achieve predictable outcomes in autotransplantation procedures. The results suggest that 3D printed replicas could be a useful tool for improving the effectiveness and success of dental autotransplantation.

Analysis of PLA/PHB Biopolymer Material with Admixture of Hydroxyapatite and Tricalcium Phosphate for Clinical Use.

One trend in tissue engineering and regenerative medicine is the development of degradable composite polymers. The aim of this study was the comprehensive analysis of Polylactic acid (PLA)/Polyhydroxybutyrate (PHB) + Hydroxyapatite (HA)/Tricalcium phosphate (TCP) material from filament production to mechanical testing of samples with different infills and the production of an implant replacement for an intervertebral disc. Filament Maker-Composer 450 (3devo; Netherlands) was used to produce filaments. Experimental samples and the implant for the intervertebral disc were made using FDM technology using a DeltiQ2 3D printer (Trilab, Czech Republic). Mechanical testing of experimental samples was performed on an Inspekt TABLE 5 kN (Hegewald & Peschke, Nossen, Germany). Microscopic analysis, cytotoxicity test, and filament diameter analysis using descriptive statistics were also part of the focus. The results of the analysis of the diameter of the filament show that the filament meets the prescribed standard. The cytotoxicity test for PLA/PHB + HA/TCP material showed no toxicity. Microscopic analysis showed an even distribution of the ceramic component in the composite polymer. Mechanical testing showed a reduction in mechanical properties with 75% and 50% of the filling of experimental samples. All experimental samples subjected to mechanical testing showed higher tensile and compressive strength values compared to the values of the mechanical properties of vertebral trabecular bones, as reported in the literature. It can therefore be concluded that the material under investigation, PLA/PHB + HA/TCP appears to be a suitable candidate for hard tissue replacement.

Impact of In Vitro Degradation on the Properties of Samples Produced by Additive Production from PLA/PHB-Based Material and Ceramics.

The present study deals with preparing a polymer-based material with incorporated ceramics and monitoring changes in properties after in vitro natural degradation. The developed material is a mixture of polymers of polylactic acid and polyhydroxybutyrate in a ratio of 85:15. Ceramic was incorporated into the prepared material, namely 10% hydroxyapatite and 10% tricalcium phosphate of the total volume. The material was processed into a filament form, and types of solid and porous samples were prepared using additive technology. These samples were immersed in three different solutions: physiological solution, phosphate-buffered saline, and Hanks' solution. Under constant laboratory conditions, changes in solution pH, material absorption, weight loss, changes in mechanical properties, and surface morphology were monitored for 170 days. The average value of the absorption of the solid sample was 7.07%, and the absorption of the porous samples was recorded at 8.33%, which means a difference of 1.26%. The least change in pH from the reference value of 7.4 was noted with the phosphate-buffered saline solution. Computed tomography was used to determine the cross-section of the samples. The obtained data were used to calculate the mechanical properties of materials after degradation. The elasticity modulus for both the full and porous samples degraded in Hanks' solution (524.53 ± 13.4 MPa) has the smallest deviation from the non-degraded reference sample (536.21 ± 22.69 MPa).

Therapy of Extensive Chronic Skin Defects after a Traumatic Injury Due to Microbial Contamination Using a Surface Implant Made of a Biocompatible Polycaprolactone-A Pilot Case Study.

This case study describes the use of additive manufacturing technology combining a biodegradable polymer material, polycaprolactone (PCL), and innovative procedures for creating superficial wound dressing, a scaffold in the therapy of extensive contaminated skin defects caused by a traumatic injury. Chronic and contaminated wounds represent a clinical problem and require intensive wound care. The application of a temporary scaffold-facilitated bridging of the wound edges resulted in faster tissue regeneration and a shorter defect closure time, compared to other conservative and surgical methods used in therapy of chronic wounds. Although this procedure has proven to be an optimal alternative to autologous transplants, further studies with a larger number of patients would be beneficial.

Review of ankle rehabilitation devices for treatment of equinus contracture.

INTRODUCTION: Equinus contracture is a serious disability and attention should be paid to proper and effective treatment. Most attention is given to neurologically impaired patients, but the incidence of equinus contracture is much higher, for example, in post-traumatic patients. In addition to conventional physical therapy, robotic rehabilitation treatment is one of the promising procedures to precede severe contraction cases and the need for surgery. AREAS COVERED: This study aims to cover the description of different types of stationary and wearable ankle rehabilitation devices suitable for the treatment of equinus contracture and point to deficiency in research, clinical trials, and launch of the market. EXPERT OPINION: This review provides insight into ankle rehabilitation devices with a focus on equinus contracture. Due to the fact that robotic devices successfully restore the condition of patients, attention should not be paid only to those with neurological impairments. This paper points that future research should be effectively linked to clinical practice with the aim of covering a wider range of disabilities and make an effort to successfully introduce devices from development into the practice.

A comparison of experimental compressive axial loading testing with a numerical simulation of topologically optimized cervical implants made by selective laser melting.

In recent years, the number of cervical interventions has increased. The stress shielding effect is a serious complication in cervical spine interventions. Topological optimization is based on finite element method structural analysis and numerical simulations. The generated design of cervical implants is made from Ti6Al4V powder by selective laser melting while the optimized cage is numerically tested for compressive axial loading and the results are compared with experimental measurement. Additive manufacturing technologies and new software possibilities in the field of structural analysis, which use the finite element method tools, help to execute implant topological optimization that is useful for clinical practice. The inner structures of the implant would be impossible to make by conventional manufacturing technologies. The resulting implant design, after modification, must fulfill strict application criteria for the area of cervical spine with respect to its material and biomechanical properties. The aim of this work was to alter the mechanical properties of the cervical intervertebral cage to address the clinical concern of the stress shielding effect by topological optimization. A methodology of cervical implant compressive axial loading numerical simulation was created, and subsequent experimental testing was done to obtain real material properties after a selective laser melting process. The weight of the optimized implant was reduced by 28.92 %. Results of the experimental testing and numerical simulation of topologically optimized design showed 10-times lower stiffness compared to the solid cage design, and the real yield strength of the optimized structure is 843.8 MPa based on experimental results.

Determination of geometrical and viscoelastic properties of PLA/PHB samples made by additive manufacturing for urethral substitution.

Additive manufacturing has a great potential for creating hard tissue substitutes, such as bone and cartilage, or soft tissues, such as vascular and skin grafts. This study is a pilot study for 3D printing of a new material mixture potentially used as a tubular substitute for urethra replacement. This new mixture is a blend of polylactic acid (PLA) and polyhydroxybutyrate (PHB). The basic aspect that affects the 3D printing process is correct material preparation and setting of 3D printer parameters. Selection of material and printing parameters depend on printing technology. The printing technology affects material behavior during printing process. The goal of preprocessing and 3D printing process is to provide stabile conditions during manufacturing to obtain usable printed samples. The study deals with preparation of material before 3D printing - material drying. Moisture in material affects material degradation and viscosity during printing. According to this, it is necessary to verify recommended drying parameters. Verification was performed by printing strand samples from dried and non-dried material and also by calculating and comparing respective viscosities that change in time. Printed strand clearly show that non-dried material degrades in less than 10 min, what leads to inappropriate application in short-time printing. Dried material shows significant stability and degrades slightly during selected time span. For metrological verification of material stability two sample types were designed and manufactured - a cubic sample which represents basic scaffold structures and a tubular one that serves as urethra substitution. Obtained results showed appropriate usability of selected technology and printing parameters for PLA / PHB material blend.