Utility of Three-Dimensional Printing for Preoperative Assessment of Children with Extra-Cranial Solid Tumors: A Systematic Review

Background: In cases with solid tumors, preoperative radiological investigations provide valuable information on the anatomy of the tumor and the adjoining structures, thus helping in operative planning. However, due to a two-dimensional view in these investigations, a detailed spatial relationship is difficult to decipher. In contrast, three-dimensional (3D) printing technology provides a precise topographic view to perform safe surgical resections of these tumors. This systematic review aimed to summarize and analyze current evidence on the utility of 3D printing in pediatric extra-cranial solid tumors. Methods: The present study was registered on PROSPERO—international prospective register of systematic reviews (registration number: CRD42020206022). PubMed, Embase, SCOPUS, and Google Scholar databases were explored with appropriate search criteria to select the relevant studies. Data were extracted to study the bibliographic information of each article, the number of patients in each study, age of the patient(s), type of tumor, organ of involvement, application of 3D printing (surgical planning, training, and/or parental education). The details of 3D printing, such as type of imaging used, software details, printing technique, printing material, and cost were also synthesized. Results: Eight studies were finally included in the systematic review. Three-dimensional printing technology was used in thirty children with Wilms tumor (n = 13), neuroblastoma (n = 7), hepatic tumors (n = 8), retroperitoneal tumor (n = 1), and synovial sarcoma (n = 1). Among the included studies, the technology was utilized for preoperative surgical planning (five studies), improved understanding of the surgical anatomy of solid organs (two studies), and improving the parental understanding of the tumor and its management (one study). Computed tomography and magnetic resonance imaging were either performed alone or in combination for radiological evaluation in these children. Different types of printers and printing materials were used in the included studies. The cost of the 3D printed models and time involved (range 10 h to 4–5 days) were reported by two studies each. Conclusions: 3D printed models can be of great assistance to pediatric surgeons in understanding the spatial relationships of tumors with the adjacent anatomic structures. They also facilitate the understanding of families, improving doctor–patient communication.

Three-Dimensional Printing Strategies for Irregularly Shaped Cartilage Tissue Engineering: Current State and Challenges

Although there have been remarkable advances in cartilage tissue engineering, construction of irregularly shaped cartilage, including auricular, nasal, tracheal, and meniscus cartilages, remains challenging because of the difficulty in reproducing its precise structure and specific function. Among the advanced fabrication methods, three-dimensional (3D) printing technology offers great potential for achieving shape imitation and bionic performance in cartilage tissue engineering. This review discusses requirements for 3D printing of various irregularly shaped cartilage tissues, as well as selection of appropriate printing materials and seed cells. Current advances in 3D printing of irregularly shaped cartilage are also highlighted. Finally, developments in various types of cartilage tissue are described. This review is intended to provide guidance for future research in tissue engineering of irregularly shaped cartilage.

Development of 3D-Printed, Liquisolid and Directly Compressed Glimepiride Tablets, Loaded with Black Seed Oil Self-Nanoemulsifying Drug Delivery System: In Vitro and In Vivo Characterization

Glimepiride is characterized by an inconsistent dissolution and absorption profile due to its limited aqueous solubility. The aim of this study was to develop glimepiride tablets using three different manufacturing techniques, as well as to study their quality attributes and pharmacokinetics behavior. Black seed oil based self-nanoemulsifying drug delivery system (SNEDDS) formulation was developed and characterized. Glimepiride liquisolid and directly compressed tablets were prepared and their pre-compression and post-compression characteristics were evaluated. Semi-solid pastes loaded with SNEDDS were prepared and used to develop three-dimensional printing tablets utilizing the extrusion technique. In vivo comparative pharmacokinetics study was conducted on Male Wistar rats using a single dose one-period parallel design. The developed SNEDDS formulation showed a particle size of 45.607 ± 4.404 nm, and a glimepiride solubility of 25.002 ± 0.273 mg/mL. All the studied tablet formulations showed acceptable pre-compression and post-compression characteristics and a difference in their in vitro drug release behavior. The surface of the liquisolid and directly compressed tablets was smooth and non-porous, while the three-dimensional printing tablets showed a few porous surfaces. The inner structure of the liquisolid tablets showed some cracks and voids between the incorporated tablet ingredients while that of the three-dimensional printing tablets displayed some tortuosity and a gel porous-like structure. Most of the computed pharmacokinetic parameters improved with the liquisolid and three-dimensional printed tablets. The relative bioavailabilities of the three-dimensional printed and liquisolid tablets compared to commercial product were 121.68% and 113.86%, respectively. Therefore, the liquisolid and three-dimensional printed tablets are promising techniques for modifying glimepiride release and improving in vivo performance but more clinical investigations are required.

3D Printing and Shaping Polymers, Composites, and Nanocomposites: A Review

Sustainable technologies are vital due to the efforts of researchers and investors who have allocated significant amounts of money and time to their development. Nowadays, 3D printing has been accepted by the main industry players, since its first establishment almost 30 years ago. It is obvious that almost every industry is related to technology, which proves that technology has a bright future. Many studies have shown that technologies have changed the methods for developing particular products. Three-dimensional printing has evolved tremendously, and currently, many new types of 3D printing machines have been introduced. In this paper, we describe the historical development of 3D printing technology including its process, types of printing, and applications on polymer materials.

Three-dimensional printing-assisted anterior and posterior combined surgery for treating a giant aggressive vertebral hemangioma

Aggressive vertebral hemangioma (AVH) is a type of non-neoplastic and congenital developmental abnormality of spinal cord blood vessels. We report the innovative application of three-dimensional (3D) printing-assisted anterior and posterior combined surgery for treating a giant AVH. This could be a novel treatment in the future. A 44-year-old man suffered from persistent neck pain and limited limb mobility for approximately 2 weeks. An imaging examination showed the destruction of C2–4 vertebral bodies, and a giant lesion invaded the spinal cord. He underwent 3D printing-assisted anterior and posterior combined surgery. Postoperatively, his symptoms of persistent neck pain and limited limb mobility were alleviated. An imaging examination showed that internal fixation and the prosthesis were fixed in place, and the spinal canal was unobstructed. Treating a giant AVH by 3D printing-assisted anterior and posterior combined surgery is feasible and effective.