scholarly journals Evaluation of Resins for Stereolithographic 3D-Printed Surgical Guides: The Response of L929 Cells and Human Gingival Fibroblasts

2017 ◽  
Vol 2017 ◽  
pp. 1-11 ◽  
Author(s):  
Christoph Kurzmann ◽  
Klara Janjić ◽  
Hassan Shokoohi-Tabrizi ◽  
Michael Edelmayer ◽  
Manuela Pensch ◽  
...  
Keyword(s):  
Cell Activity ◽  
Cost Effective ◽  
Gingival Fibroblasts ◽  
L929 Cells ◽  
Surgical Guides ◽  
Culture Model ◽  
Culture Models ◽  
3D Printed ◽  
Dental Offices ◽  
The Impact

Additive manufacturing is becoming increasingly important in dentistry for the production of surgical guides. The development of cost-effective desktop stereolithography (SLA) printing systems and the corresponding resins makes this novel technique accessible to dental offices and dental laboratories. The aim of the study was to reveal the response of soft tissue cells to Clear and Dental SG resins used in desktop SLA printing systems at different stages of processing. Cell activity of L929 cells and gingival fibroblasts (GF) in response to the materials was examined in indirect and direct monolayer culture models and a direct spheroid culture model based on MTT, resazurin-based toxicity assays, and live-dead staining. Overall we found that the impact of Clear and Dental SG resins on L929 and GF depends on the processing stage of the materials. Liquid Clear resin induced a stronger reduction of cell activity compared to Dental SG resin. Printing and postcuring reduced the impact on cell activity and viability. As in-house 3D printing for surgical guides is getting integrated in the digital workflow, our data suggest that careful adherence to processing guidelines—especially postcuring—is of clinical relevance.

scholarly journals The impact of 3D-printed LAY-FOMM 40 and LAY-FOMM 60 on L929 cells and human oral fibroblasts

2020 ◽  
Author(s):  
Gunpreet Oberoi ◽  
Sophie Nitsch ◽  
Klara Janjić ◽  
Hassan Shokoohi-Tabrizi ◽  
Andreas Moritz ◽  
...  
Keyword(s):  
Fused Deposition Modeling ◽  
Cell Activity ◽  
Toxicity Assay ◽  
L929 Cells ◽  
Fused Deposition ◽  
Direct Model ◽  
Culture Models ◽  
3D Printed ◽  
The Impact ◽  
Oral Cells

Abstract Objectives LAY-FOMM is a promising material for FDA-approved Fused Deposition Modeling (FDM) applications in drug delivery. Here we investigated the impact on oral cells. Materials and methods We evaluated the impact of 3D-printed LAY-FOMM 40, LAY-FOMM 60, and biocompatible polylactic acid (PLA) on the activity of murine L929 cells, gingival fibroblasts (GF), and periodontal ligament fibroblasts (PDLF) using indirect (samples on cells), direct monolayer culture models (cells on samples), and direct spheroid cultures with resazurin-based toxicity assay, confirmed by MTT and Live-dead staining. The surface topography was evaluated with scanning electron microscopy. Results The materials LAY-FOMM 40 and LAY-FOMM 60 led to a reduction in resazurin conversion in L929 cells, GF, and PDLF, higher than the impact of PLA in indirect and direct culture models. Fewer vital cells were found in the presence of LAY-FOMM 40 and 60 than PLA, in the staining in both models. In the direct model, LAY-FOMM 40 and PLA showed less impact on viability in the resazurin-based toxicity assay than in the indirect model. Spheroid microtissues showed a reduction of cell activity of GF and PDLF with LAY-FOMM 40 and 60. Conclusion Overall, we found that LAY-FOMM 40 and LAY-FOMM 60 can reduce the activity of L292 and oral cells. Based on the results from the PLA samples, the direct model seems more reliable than the indirect model. Clinical relevance A material modification is desired in terms of biocompatibility as it can mask the effect of drugs and interfere with the function of the 3D-printed device.

scholarly journals Accuracy of a workflow using sleeveless 3D printed surgical guides made from a cost‐effective and biodegradable material: An in vitro study

2019 ◽  
Vol 30 (S19) ◽  
pp. 519-519 ◽  
Author(s):  
Valentin Hromadnik ◽  
Stefano Pieralli ◽  
Benedikt Spies ◽  
Florian Beuer ◽  
Christian Wesemann
Keyword(s):  
In Vitro Study ◽  
Cost Effective ◽  
Vitro Study ◽  
Biodegradable Material ◽  
Surgical Guides ◽  
3D Printed

A Study on the Impact of Chinese Family Culture on Citizens' Voluntary Organ Donation

2020 ◽  
Author(s):  
Aijing Luo ◽  
Haiyan He ◽  
Wenzhao Xie ◽  
Zehua Xu ◽  
Wei Ouyang ◽  
...  
Keyword(s):  
Organ Donation ◽  
Family Members ◽  
Chinese Family ◽  
Family Culture ◽  
Willingness To Donate ◽  
Culture Model ◽  
The Family ◽  
Culture Models ◽  
Social And Cultural Factors ◽  
The Impact

Abstract Objectives: Family members’ attitude is the key factor in organ donation. This study aimed to analyze the attitude and willingness of families towards organ donation and to explore the impact of Chinese family culture on voluntary organ donation.Methods: Taking the family as a unit, a total of 15 families (59 family members) were interviewed using the semi-structured interviews.Results: Among the 59 participants, 58 had heard of organ donation, 30 were unwilling to donate organs, 25 had an intention to donate, and 13 were very taboo about it. 29 weren’t giving consent for family members’ donation, only 8 supported families to sign up as donors. Particularly, 7 participants could donate their organs but wouldn’t donate organs of family members. The family culture models were divided into the patriarchal family culture model (4 families), independent family culture model (8 families), patriarchal subversion family culture model (3 families). Based on the influence of social and cultural factors (taking national policy as an example) on the willingness to donate organs of relatives, the family culture models were divided into the stubborn family culture model (3 families), swing family culture model(9 families), and selfless dedication family culture model(3 families). Conclusions: Organ donation is still a taboo topic in Chinese families. Although the patriarchal family cultural model is no longer dominant, the father's thoughts and views still play an essential role in the whole family. Most families belong to the swing family culture model, and the willingness to donate is greatly influenced by social and cultural factors.

scholarly journals A Composite Lactide-Mineral 3D-Printed Scaffold for Bone Repair and Regeneration

2021 ◽  
Vol 9 ◽  
Author(s):  
Rayan Fairag ◽  
Li Li ◽  
Jose Luis Ramirez-GarciaLuna ◽  
M. Scott Taylor ◽  
Brian Gaerke ◽  
...  
Keyword(s):  
Disease Transmission ◽  
Bone Grafting ◽  
Bone Repair ◽  
Donor Site ◽  
Tumor Resection ◽  
Cell Activity ◽  
Fused Deposition ◽  
Matrix Deposition ◽  
3D Printed ◽  
The Impact

Orthopedic tumor resection, trauma, or degenerative disease surgeries can result in large bone defects and often require bone grafting. However, standard autologous bone grafting has been associated with donor site morbidity and/or limited quantity. As an alternate, allografts with or without metallic or polyether-etherketone have been used as grafting substitutes. However, these may have drawbacks as well, including stress shielding, pseudarthrosis, disease-transmission, and infection. There is therefore a need for alternative bone substitutes, such as the use of mechanically compliant three-dimensional (3D)-printed scaffolds. Several off-the-shelf materials are available for low-cost fused deposition 3D printing such as polylactic acid (PLA) and polycaprolactone (PCL). We have previously described the feasibility of 3D-printed PLA scaffolds to support cell activity and extracellular matrix deposition. In this study, we investigate two medical-grade filaments consistent with specifications found in American Society for Testing and Materials (ASTM) standard for semi-crystalline polylactide polymers for surgical implants, a pure polymer (100M) and a copolymeric material (7415) for their cytocompatibility and suitability in bone tissue engineering. Moreover, we assessed the impact on osteo-inductive properties with the addition of beta-tricalcium phosphate (β-TCP) minerals and assessed their mechanical properties. 100M and 7415 scaffolds with the additive β-TCP demonstrated superior mesenchymal stem cells (MSCs) differentiation detected via increased alkaline phosphatase activity (6-fold and 1.5-fold, respectively) and mineralized matrix deposition (14-fold and 5-fold, respectively) in vitro. Furthermore, we evaluated in vivo compatibility, biosafety and bone repair potential in a rat femur window defect model. 100M+β-TCP implants displayed a positive biosafety profile and showed significantly enhanced new bone formation compared to 100M implants evidenced by μCT (39 versus 25% bone volume/tissue volume ratio) and histological analysis 6 weeks post-implantation. These scaffolds are encouraging composite biomaterials for repairing bone applications with a great potential for clinical translation. Further analyses are required with appropriate evaluation in a larger critical-sized defect animal model with long-term follow-up.

Regulatory and sustainability initiatives lead to improved polyaminopolyamide epichlorohydrin (PAE) wet-strength resins and paper products

TAPPI Journal ◽  
2018 ◽  
Vol 17 (09) ◽  
pp. 519-532 ◽  
Author(s):  
Mark Crisp ◽  
Richard Riehle
Keyword(s):  
Health And Safety ◽  
Cost Effective ◽  
Worker Safety ◽  
Regulatory Requirements ◽  
Wet Strength ◽  
The Past ◽  
Consumer Safety ◽  
Federal Institute ◽  
Sustainability Initiatives ◽  
The Impact

Polyaminopolyamide-epichlorohydrin (PAE) resins are the predominant commercial products used to manufacture wet-strengthened paper products for grades requiring wet-strength permanence. Since their development in the late 1950s, the first generation (G1) resins have proven to be one of the most cost-effective technologies available to provide wet strength to paper. Throughout the past three decades, regulatory directives and sustainability initiatives from various organizations have driven the development of cleaner and safer PAE resins and paper products. Early efforts in this area focused on improving worker safety and reducing the impact of PAE resins on the environment. These efforts led to the development of resins containing significantly reduced levels of 1,3-dichloro-2-propanol (1,3-DCP) and 3-monochloropropane-1,2-diol (3-MCPD), potentially carcinogenic byproducts formed during the manufacturing process of PAE resins. As the levels of these byproducts decreased, the environmental, health, and safety (EH&S) profile of PAE resins and paper products improved. Recent initiatives from major retailers are focusing on product ingredient transparency and quality, thus encouraging the development of safer product formulations while maintaining performance. PAE resin research over the past 20 years has been directed toward regulatory requirements to improve consumer safety and minimize exposure to potentially carcinogenic materials found in various paper products. One of the best known regulatory requirements is the recommendations of the German Federal Institute for Risk Assessment (BfR), which defines the levels of 1,3-DCP and 3-MCPD that can be extracted by water from various food contact grades of paper. These criteria led to the development of third generation (G3) products that contain very low levels of 1,3-DCP (typically <10 parts per million in the as-received/delivered resin). This paper outlines the PAE resin chemical contributors to adsorbable organic halogens and 3-MCPD in paper and provides recommendations for the use of each PAE resin product generation (G1, G1.5, G2, G2.5, and G3).

Exploring the Benefits of Early Contractor Involvement (ECI) and the Mechanism for Automated 5D BIM Quantification Process in Offsite Modular Construction

2016 ◽  
Author(s):  
Tochukwu Moses ◽  
David Heesom ◽  
David Oloke ◽  
Martin Crouch
Keyword(s):  
Effective Means ◽  
Cost Effective ◽  
Modular Construction ◽  
Automated Quantification ◽  
Building Information ◽  
Project Risks ◽  
Value Add ◽  
The Uk ◽  
The Impact ◽  
Level 2

The UK Construction Industry through its Government Construction Strategy has recently been mandated to implement Level 2 Building Information Modelling (BIM) on public sector projects. This move, along with other initiatives is key to driving a requirement for 25% cost reduction (establishing the most cost-effective means) on. Other key deliverables within the strategy include reduction in overall project time, early contractor involvement, improved sustainability and enhanced product quality. Collaboration and integrated project delivery is central to the level 2 implementation strategy yet the key protocols or standards relative to cost within BIM processes is not well defined. As offsite construction becomes more prolific within the UK construction sector, this construction approach coupled with BIM, particularly 5D automated quantification process, and early contractor involvement provides significant opportunities for the sector to meet government targets. Early contractor involvement is supported by both the industry and the successive Governments as a credible means to avoid and manage project risks, encourage innovation and value add, making cost and project time predictable, and improving outcomes. The contractor is seen as an expert in construction and could be counter intuitive to exclude such valuable expertise from the pre-construction phase especially with the BIM intent of äóÖbuild it twiceäó», once virtually and once physically. In particular when offsite construction is used, the contractoräó»s construction expertise should be leveraged for the virtual build in BIM-designed projects to ensure a fully streamlined process. Building in a layer of automated costing through 5D BIM will bring about a more robust method of quantification and can help to deliver the 25% reduction in overall cost of a project. Using a literature review and a case study, this paper will look into the benefits of Early Contractor Involvement (ECI) and the impact of 5D BIM on the offsite construction process.

Pound Wise and Penny Foolish? Weight Loss and The Dynamics of Health Care Spending

2011 ◽  
Vol 14 (2) ◽  
Author(s):  
Thomas G Koch
Keyword(s):  
Weight Loss ◽  
Cost Savings ◽  
Cost Effective ◽  
Economic Consequences ◽  
Health Care Spending ◽  
Order Of Magnitude ◽  
Dynamic Measures ◽  
The Cost ◽  
The Impact ◽  
The Relationship

Current estimates of obesity costs ignore the impact of future weight loss and gain, and may either over or underestimate economic consequences of weight loss. In light of this, I construct static and dynamic measures of medical costs associated with body mass index (BMI), to be balanced against the cost of one-time interventions. This study finds that ignoring the implications of weight loss and gain over time overstates the medical-cost savings of such interventions by an order of magnitude. When the relationship between spending and age is allowed to vary, weight-loss attempts appear to be cost-effective starting and ending with middle age. Some interventions recently proven to decrease weight may also be cost-effective.

Bone tissue engineering in the greater omentum with computer-aided design/computer-aided manufacturing scaffolds is enhanced by a periosteum transplant

2020 ◽  
Author(s):  
Hendrik Naujokat ◽  
Klaas Loger ◽  
Juliane Schulz ◽  
Yahya Açil ◽  
Jörg Wiltfang
Keyword(s):  
Bone Formation ◽  
Bone Tissue ◽  
Computer Aided Design ◽  
Bone Tissue Regeneration ◽  
Histological Evaluation ◽  
Greater Omentum ◽  
Collagen Membrane ◽  
Computer Aided ◽  
3D Printed ◽  
The Impact

Aim: This study aimed to evaluate two different vascularized bone flap scaffolds and the impact of two barrier membranes for the reconstruction of critical-size bone defects. Materials & methods: 3D-printed scaffolds of biodegradable calcium phosphate and bioinert titanium were loaded with rhBMP-2 bone marrow aspirate, wrapped by a collagen membrane or a periosteum transplant and implanted into the greater omentum of miniature pigs. Results: Histological evaluation demonstrated significant bone formation within the first 8 weeks in both scaffolds. The periosteum transplant led to enhanced bone formation and a homogenous distribution in the scaffolds. The omentum tissue grew out a robust vascular supply. Conclusion: Endocultivation using 3D-printed scaffolds in the greater omentum is a very promising approach in defect-specific bone tissue regeneration.

Motivating Compliance: Firm Response to Mandatory Disclosure Policies

2018 ◽  
Vol 32 (2) ◽  
pp. 103-119
Author(s):  
Colleen M. Boland ◽  
Chris E. Hogan ◽  
Marilyn F. Johnson
Keyword(s):  
Conflict Of Interest ◽  
Low Cost ◽  
Cost Effective ◽  
Data Availability ◽  
Policy Adoption ◽  
Future Research ◽  
Regulated Firms ◽  
Firm Response ◽  
Disclosure Rules ◽  
The Impact

SYNOPSIS Mandatory existence disclosure rules require an organization to disclose a policy's existence, but not its content. We examine policy adoption frequencies in the year immediately after the IRS required mandatory existence disclosure by nonprofits of various governance policies. We also examine adoption frequencies in the year of the subsequent change from mandatory existence disclosure to a disclose-and-explain regime that required supplemental disclosures about the content and implementation of conflict of interest policies. Our results suggest that in areas where there is unclear regulatory authority, mandatory existence disclosure is an effective and low cost regulatory device for encouraging the adoption of policies desired by regulators, provided those policies are cost-effective for regulated firms to implement. In addition, we find that disclose-and-explain regulatory regimes provide stronger incentives for policy adoption than do mandatory existence disclosure regimes and also discourage “check the box” behavior. Future research should examine the impact of mandatory existence disclosure rules in the year that the regulation is implemented. Data Availability: Data are available from sources cited in the text.

scholarly journals QOL-36. USE OF CANNABINOIDS IN THE PEDIATRIC CENTRAL NERVOUS SYSTEM TUMOR POPULATION

2020 ◽  
Vol 22 (Supplement_3) ◽  
pp. iii438-iii438
Author(s):  
Kathleen Dorris ◽  
Jessica Channell ◽  
Ashley Mettetal ◽  
Molly Hemenway ◽  
Natalie Briones ◽  
...  
Keyword(s):  
Quality Of Life ◽  
Central Nervous System ◽  
Nervous System ◽  
Cell Activity ◽  
Cns Tumors ◽  
Low Grade ◽  
Tumor Type ◽  
Central Nervous System Tumor ◽  
The Impact

Abstract BACKGROUND Cannabinoids, including cannabidiol (CBD) and tetrahydrocannabinol (THC), are a class of compounds found in marijuana. Numerous studies in adults have examined cannabinoid use in management of cancer-related symptoms such as nausea, anorexia, and pain. Less is known about the use in the pediatric oncology population. METHODS A prospective observational study has been ongoing since 2016 at Children’s Hospital Colorado to evaluate cannabinoids’ impact using PedsQL™ modules on quality of life of pediatric patients with central nervous system (CNS) tumors who are 2–18 years old. Laboratory assessments of T-cell activity and pharmacokinetics of CBD, THC and associated metabolites are in process. Diaries with exploratory information on cannabinoid use patterns are being collected. RESULTS Thirty-three patients (14:19; male:female) have been enrolled with a median age of 6.4 years (range, 2.9–17.7 years). The most common tumor type in enrolled patients is embryonal tumors (13/33; 39%). Nine (27%) patients have low-grade glial/glioneuronal tumors, and eight (24%) had high-grade/diffuse midline gliomas. The remaining patients had ependymoma or craniopharyngioma. The median time on cannabinoids is 9 months. Most (n=20) patients have used oral products with CBD and THC. One patient continues on cannabinoid therapy in follow up. Preliminary immune function analyses identified impaired neutrophil superoxide anion production and chemotaxis in patients taking cannabinoids at early time points on therapy. CONCLUSIONS Families of children with various CNS tumors are pursuing cannabinoid therapy for both antitumor and supportive care purposes. Analysis of the impact of cannabinoids on patients’ quality of life is ongoing.

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