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Reconstruction of the facial skeleton is challenging for surgeons because of difficulties in proper shape restoration and maintenance of the proper long-term effect. ZrO2 implant application can be a solution with many advantages (e.g., osseointegration, stability, and radio-opaqueness) and lacks the disadvantages of other biomaterials (e.g., metalosis, radiotransparency, and no osseointegration) or autologous bone (e.g., morbidity, resorption, and low accuracy). We aimed to evaluate the possibility of using ZrO2 implants as a new application of this material for craniofacial bone defect reconstruction. First, osteoblast (skeleton-related cell) cytotoxicity and genotoxicity were determined in vitro by comparing ZrO2 implants and alumina particle air-abraded ZrO2 implants to the following: 1. a titanium alloy (standard material); 2. ultrahigh-molecular-weight polyethylene (a modern material used in orbital surgery); 3. a negative control (minimally cytotoxic or genotoxic agent action); 4. a positive control (maximally cytotoxic or genotoxic agent action). Next, 14 custom in vivo clinical ZrO2 implants were manufactured for post-traumatologic periorbital region reconstruction. The soft tissue position improvement in photogrammetry was recorded, and clinical follow-up was conducted at least 6 years postoperatively. All the investigated materials revealed no cytotoxicity. Alumina particle air-abraded ZrO2 implants showed genotoxicity compared to those without subjection to air abrasion ZrO2, which were not genotoxic. The 6-month and 6- to 8-year clinical results were aesthetic and stable. Skeleton reconstructions using osseointegrated, radio-opaque, personalized implants comprising ZrO2 material are the next option for craniofacial surgery.
Marcin Kozakiewicz; Tomasz Gmyrek; Radosław Zajdel; Bartłomiej Konieczny. Custom-Made Zirconium Dioxide Implants for Craniofacial Bone Reconstruction. Materials 2021, 14, 840 .
AMA StyleMarcin Kozakiewicz, Tomasz Gmyrek, Radosław Zajdel, Bartłomiej Konieczny. Custom-Made Zirconium Dioxide Implants for Craniofacial Bone Reconstruction. Materials. 2021; 14 (4):840.
Chicago/Turabian StyleMarcin Kozakiewicz; Tomasz Gmyrek; Radosław Zajdel; Bartłomiej Konieczny. 2021. "Custom-Made Zirconium Dioxide Implants for Craniofacial Bone Reconstruction." Materials 14, no. 4: 840.
The successful restoration of teeth requires a good connection between the inlay and natural tissue. A strong bond may improve retention and reinforce tooth structure. The purpose of this study was to evaluate the influence of cement layer thickness on contraction stress generated during photopolymerization, and to determine the changes in stress state of the cement occurring during aging in water (over 84 days). Two cements were used: resin composite cement (NX3) and self-adhesive resin cement (Maxcem Elite Chroma). A cylindrical sample made of CuZn alloy was used to imitate the inlay. The stress state was measured by photoelastic analysis. The contraction stress of the inlay restoration was calculated for cement layer thicknesses of 25 µm, 100 µm, 200 µm, and 400 µm. For both tested materials, the lowest contraction stress was observed for the thinnest layer (25 µm), and this increased with thickness. Following water immersion, a significant reduction in contraction stress was observed due to hygroscopic expansion. Applying a thin layer (approximately 25 µm) of composite and self-adhesive resin cements resulted in high levels of expansion stresses (over −6 MPa) after water aging.
Grzegorz Sokolowski; Michal Krasowski; Agata Szczesio-Wlodarczyk; Bartlomiej Konieczny; Jerzy Sokolowski; Kinga Bociong. The Influence of Cement Layer Thickness on the Stress State of Metal Inlay Restorations—Photoelastic Analysis. Materials 2021, 14, 599 .
AMA StyleGrzegorz Sokolowski, Michal Krasowski, Agata Szczesio-Wlodarczyk, Bartlomiej Konieczny, Jerzy Sokolowski, Kinga Bociong. The Influence of Cement Layer Thickness on the Stress State of Metal Inlay Restorations—Photoelastic Analysis. Materials. 2021; 14 (3):599.
Chicago/Turabian StyleGrzegorz Sokolowski; Michal Krasowski; Agata Szczesio-Wlodarczyk; Bartlomiej Konieczny; Jerzy Sokolowski; Kinga Bociong. 2021. "The Influence of Cement Layer Thickness on the Stress State of Metal Inlay Restorations—Photoelastic Analysis." Materials 14, no. 3: 599.
This paper describes a novel method for the experimental validation of numerically optimised turbomachinery components. In the field of additive manufacturing, numerical models still need to be improved, especially with the experimental data. The paper presents the operational characteristics of a compressor wheel, measured during experimental research. The validation process included conducting a computational flow analysis and experimental tests of two compressor wheels: The aluminium wheel and the 3D printed wheel (made of a polymer material). The chosen manufacturing technology and the results obtained made it possible to determine the speed range in which the operation of the tested machine is stable. In addition, dynamic destructive tests were performed on the polymer disc and their results were compared with the results of the strength analysis. The tests were carried out at high rotational speeds (up to 120,000 rpm). The results of the research described above have proven the utility of this technology in the research and development of high-speed turbomachines operating at speeds up to 90,000 rpm. The research results obtained show that the technology used is suitable for multi-variant optimization of the tested machine part. This work has also contributed to the further development of numerical models.
Artur Andrearczyk; Bartlomiej Konieczny; Jerzy Sokołowski. Additively Manufactured Parts Made of a Polymer Material Used for the Experimental Verification of a Component of a High-Speed Machine with an Optimised Geometry—Preliminary Research. Polymers 2020, 13, 137 .
AMA StyleArtur Andrearczyk, Bartlomiej Konieczny, Jerzy Sokołowski. Additively Manufactured Parts Made of a Polymer Material Used for the Experimental Verification of a Component of a High-Speed Machine with an Optimised Geometry—Preliminary Research. Polymers. 2020; 13 (1):137.
Chicago/Turabian StyleArtur Andrearczyk; Bartlomiej Konieczny; Jerzy Sokołowski. 2020. "Additively Manufactured Parts Made of a Polymer Material Used for the Experimental Verification of a Component of a High-Speed Machine with an Optimised Geometry—Preliminary Research." Polymers 13, no. 1: 137.
Complex dental components which are individually tailored to the patient can be obtained due to new additive manufacturing technology. This paper reviews the metallic powders used in dental applications, the fabrication process (build orientation, process parameters) and post-processing processes (stress relieving, surface finishing). A review of the literature was performed using PubMed, ScienceDirect, Mendeley and Google Scholar. Over eighty articles were selected based on relevance to this review. This paper attempts to include the latest research from 2010 until 2020, however, older manuscripts (10 articles) were also selected. Over 1200 records were identified through the search; these were screened for title and/or summary. Over eighty articles were selected based on relevance to this review. In order to obtain a product which can be used in clinical applications, the appropriate manufacturing parameters should be selected. A discussion was made on optimal selective laser melting (SLM) parameters in dentistry. In addition, this paper includes a critical review of applied thermal treatment methods for Co–Cr alloys used in dentistry.
Bartłomiej Konieczny; Agata Szczesio-Wlodarczyk; Jerzy Sokolowski; Kinga Bociong. Challenges of Co–Cr Alloy Additive Manufacturing Methods in Dentistry—The Current State of Knowledge (Systematic Review). Materials 2020, 13, 3524 .
AMA StyleBartłomiej Konieczny, Agata Szczesio-Wlodarczyk, Jerzy Sokolowski, Kinga Bociong. Challenges of Co–Cr Alloy Additive Manufacturing Methods in Dentistry—The Current State of Knowledge (Systematic Review). Materials. 2020; 13 (16):3524.
Chicago/Turabian StyleBartłomiej Konieczny; Agata Szczesio-Wlodarczyk; Jerzy Sokolowski; Kinga Bociong. 2020. "Challenges of Co–Cr Alloy Additive Manufacturing Methods in Dentistry—The Current State of Knowledge (Systematic Review)." Materials 13, no. 16: 3524.
Background: In the literature, no information on plates for low-neck mandibular condylar osteosynthesis can be found, despite the fact that 30 plate designs have already been published. The aim of this study was to compare any dedicated plates for possible use in low-neck condylar fracture osteosynthesis. Methods: The force required for 1-mm displacement of the fixed fracture fragments and incidents of screw loosening were recorded on polyurethane mandibles among 16 designs of titanium plates fixed by 6-mm screws in a 2.0 system. Results: Double-straight plate fixation was the mechanical gold standard (15.2 ± 3.5 N), followed by A-shape Condylar Plates (14.9 ± 2.1 N), X-shape Condylar Plates (14.2 ± 1.3 N) and Auto Repositioning Plates (11.8 ± 2.4 N). Screw loosening was uncommon, as a minimum of three screws were placed into the condylar part. Fewer screws were lost from the ramus part of the fixation if the plate was attached to the condylar part by three screws. Often, the stability of the ramus screws was lost when there were only two fixing screws in the condyle (p < 0.001). Conclusions: It is advisable to consider the mechanical advantages as one decides which plate to choose for open rigid internal fixation in low-neck condylar fractures, or to only be aware of the significant differences in mobility within the fracture line after fixation with different dedicated plates.
Marcin Kozakiewicz; Rafał Zieliński; Bartłomiej Konieczny; Michał Krasowski; Jakub Okulski. Open Rigid Internal Fixation of Low-Neck Condylar Fractures of the Mandible: Mechanical Comparison of 16 Plate Designs. Materials 2020, 13, 1953 .
AMA StyleMarcin Kozakiewicz, Rafał Zieliński, Bartłomiej Konieczny, Michał Krasowski, Jakub Okulski. Open Rigid Internal Fixation of Low-Neck Condylar Fractures of the Mandible: Mechanical Comparison of 16 Plate Designs. Materials. 2020; 13 (8):1953.
Chicago/Turabian StyleMarcin Kozakiewicz; Rafał Zieliński; Bartłomiej Konieczny; Michał Krasowski; Jakub Okulski. 2020. "Open Rigid Internal Fixation of Low-Neck Condylar Fractures of the Mandible: Mechanical Comparison of 16 Plate Designs." Materials 13, no. 8: 1953.
Background: In the literature no information about plates for the high-neck mandibular condylar osteosynthesis could be found despite that 30 plate designs have been published. The main course consider the basal condylar or diacapitular fractures. The aim of the study was to test mechanically all available designs (only 4 of 30 was proper) on polyurethane mandibles using an individually designed clamping system. Methods: Forces required for a 1 mm displacement of fixed fracture fragments and incidents of screw loosening were recorded. Results: It has occured that dedicated plates for fixation are much weaker than set of two straight plates (p < 0.0001). General observation is the bigger plate and more screws, the better rigid stable osteosynthesis of mandibular condyle, however, there are limitations in plates design for high-neck fractures resulted in restricted operation field. Conclusion: Double straight plates occured to be the best mechanical fixation for high-neck fractures of the mandibular condyle. Maybe other existing plates could be used but only after prebending or that fracture required novel dedicated plates design.
Rafał Zieliński; Marcin Kozakiewicz; Bartłomiej Konieczny; Michał Krasowski; Jakub Okulski. Mechanical Evaluation of Titanium Plates for Osteoesynthesis High Neck Condylar Fracture of Mandible. Materials 2020, 13, 592 .
AMA StyleRafał Zieliński, Marcin Kozakiewicz, Bartłomiej Konieczny, Michał Krasowski, Jakub Okulski. Mechanical Evaluation of Titanium Plates for Osteoesynthesis High Neck Condylar Fracture of Mandible. Materials. 2020; 13 (3):592.
Chicago/Turabian StyleRafał Zieliński; Marcin Kozakiewicz; Bartłomiej Konieczny; Michał Krasowski; Jakub Okulski. 2020. "Mechanical Evaluation of Titanium Plates for Osteoesynthesis High Neck Condylar Fracture of Mandible." Materials 13, no. 3: 592.