Comparison of sheep scapula models created with polylactic acid and thermoplastic polyurethane filaments by three-dimensional modelling

Biodegradable Polymers in Veterinary Medicine-A Review

During the past two decades, tremendous progress has been made in the development of biodegradable polymeric materials for various industrial applications, including human and veterinary medicine. They are promising alternatives to commonly used non-degradable polymers to combat the global plastic waste crisis. Among biodegradable polymers used, or potentially applicable to, veterinary medicine are natural polysaccharides, such as chitin, chitosan, and cellulose as well as various polyesters, including poly(ε-caprolactone), polylactic acid, poly(lactic-co-glycolic acid), and polyhydroxyalkanoates produced by bacteria. They can be used as implants, drug carriers, or biomaterials in tissue engineering and wound management. Their use in veterinary practice depends on their biocompatibility, inertness to living tissue, mechanical resistance, and sorption characteristics. They must be designed specifically to fit their purpose, whether it be: (1) facilitating new tissue growth and allowing for controlled interactions with living cells or cell-growth factors, (2) having mechanical properties that address functionality when applied as implants, or (3) having controlled degradability to deliver drugs to their targeted location when applied as drug-delivery vehicles. This paper aims to present recent developments in the research on biodegradable polymers in veterinary medicine and highlight the challenges and future perspectives in this area.

Use of 3D-printed polylactic acid/bioceramic composite scaffolds for bone tissue engineering in preclinical in vivo studies: A systematic review

3D-printed composite scaffolds have emerged as an alternative to deal with existing limitations when facing bone reconstruction. The aim of the study was to systematically review the feasibility of using PLA/bioceramic composite scaffolds manufactured by 3D-printing technologies as bone grafting materials in preclinical in vivo studies. Electronic databases were searched using specific search terms, and thirteen manuscripts were selected after screening. The synthesis of the scaffolds was carried out using mainly extrusion-based techniques. Likewise, hydroxyapatite was the most used bioceramic for synthesizing composites with a PLA matrix. Among the selected studies, seven were conducted in rats and six in rabbits, but the high variability that exists regarding the experimental process made it difficult to compare them. Regarding the results, PLA/Bioceramic composite scaffolds have shown to be biocompatible and mechanically resistant. Preclinical studies elucidated the ability of the scaffolds to be used as bone grafts, allowing bone growing without adverse reactions. In conclusion, PLA/Bioceramics scaffolds have been demonstrated to be a promising alternative for treating bone defects. Nevertheless, more care should be taken when designing and performing in vivo trials, since the lack of standardization of the processes, which prevents the comparison of the results and reduces the quality of the information. STATEMENT OF SIGNIFICANCE: 3D-printed polylactic acid/bioceramic composite scaffolds have emerged as an alternative to deal with existing limitations when facing bone reconstruction. Since preclinical in vivo studies with animal models represent a mandatory step for clinical translation, the present manuscript analyzed and discussed not only those aspects related to the selection of the bioceramic material, the synthesis of the implants and their characterization. But provides a new approach to understand how the design and perform of clinical trials, as well as the selection of the analysis methods, may affect the obtained results, by covering authors' knowledgebase from veterinary medicine to biomaterial science. Thus, this study aims to systematically review the feasibility of using polylactic acid/bioceramic scaffolds as grafting materials in preclinical trials.

Students' performance in teaching neuroanatomy using traditional and technology-based methods

The use of digital teaching resources became widespread and very helpful during the COVID-19 pandemic as an alternative to a traditional course with cadavers. Technologies such as augmented reality (AR), virtual reality (VR), 3D models, video lectures and other online resources enable three-dimensional visualization of the anatomical structures and allow students to learn more interactively. The aim of this study was to compare students' performance in the traditional anatomical courses in teaching neuroanatomy and technology-based learning methods such as video lectures, 3D models and 3D printed specimens. Four groups of first-year students of Veterinary Faculty established for the practical classes during the academic year 2021/2022 took part in this research. The total number of students participating in this research was 72. Each group attended separately the theoretical lecture with a demonstration based on a different technique; the control group used formalized specimens, while the three experimental groups used video lectures, 3D models and 3D printed specimens, respectively. Subsequently, all groups completed the same questionnaire testing their short-term memory of the neuroanatomical structures. After four weeks students were tested for their long-term memory of the neuroanatomy lecture with the follow-up test containing an identical list of questions. The test scores using video lectures and 3D printed models were significantly higher compared with the group that learned in the traditional way. This study suggests that alternative approaches such as technology-based digital methods can facilitate memorization of anatomical terms and structures in a more interactive and sensory engaging way of learning.

Bonding and Strengthening the PLA Biopolymer in Multi-Material Additive Manufacturing

3D printing is a revolutionary additive manufacturing method that enables rapid prototyping and design flexibility. A variety of thermoplastic polymers can be used in printing. As it is necessary to reduce the consumption of petrochemical resources, alternative solutions are being researched, and the interest in using bioplastics and biocomposites is constantly growing. Often, however, the properties of biopolymers are insufficient and need to be improved to compete with petroleum-based plastics. The paper aims to analyze the available information on elements produced from more than one material, with additive manufacturing resulting from 3D printing using biopolymer Polylactic Acid (PLA). The study notes the possibility of modifying and improving the properties of PLA using layered printing or by modifying PLA filaments. Several modifications improving and changing the properties of PLA were also noted, including printing parameters when combined with other materials: process temperatures, filling, and surface development for various sample geometries.