An improved dental composite with potent antibacterial function

A new BisGMA-based antibacterial dental composite has been formulated and evaluated. Compressive strength and bacterial viability were utilized to evaluate the formed composites. It was found that the new composite exhibited a significantly enhanced antibacterial function along with improved mechanical and physical properties. The bromine-containing derivative-modified composite was more potent in antibacterial activity than the chlorine-containing composite. The modified composites also exhibited an increase of 30–53% in compressive yield strength, 15–30% in compressive modulus, 15–33% in diametral tensile strength and 6–20% in flexural strength, and a decrease of 57–76% in bacterial viability, 23–37% in water sorption, 8–15% in shrinkage, 8–13% in compressive strength, and similar degree of conversion, than unmodified composite. It appears that this experimental composite may possibly be introduced to dental clinics as an attractive dental restorative due to its improved properties as well as enhanced antibacterial function

Coating of Polyvinylchloride for Reduced Cell / Bacterial Adhesion and Antibacterial Properties

Indiana University-Purdue University Indianapolis (IUPUI)A Polyvinylchloride surface was modified by coating a biocompatible, hydrophilic and antibacterial polymer by a mild surface modification method. The surface was first activated and then functionalized, followed by coating with polymer. The surface functionality was evaluated using cell adhesion, bacterial adhesion and bacterial viability for polymers with antibacterial properties. 3T3 mouse fibroblast cells were used for cell adhesion, Pseudomonas aeruginosa, Escherichia coli, and Staphylococcus aureus were used for bacterial adhesion in the first study, Pseudomonas aeruginosa and Staphylococcus aureus were used for bacterial adhesion and antibacterial activity in the second study. Chapter 2 reports how we synthesized, immobilized and evaluated a novel hydrophilic polymer with anti-fouling properties onto surface of polyvinylchloride via an effective and mild surface coating technique. The polyvinylchloride surface was first activated by azidation as well as amination, and then tethering a newly synthesized hydrophilic and biocompatible polyvinylpyrrolidone having pendent reactive succinimide functionality onto the surface. Results show that the coated hydrophilic polymer significantly reduced the 3T3 fibroblast cell adhesion as well as the adhesion of the three bacterial species. Chapter 3 reports how we prepared, immobilized and evaluated an antibacterial and anti-fouling polymer onto polyvinylchloride surface following an efficient and simple method of surface modification. The surface coated with a terpolymer constructed with N-vinylpyrrolidone, 3,4-Dichloro-5-hydroxy-2(5H)-furanone derivative and succinimide residue was evaluated with cell adhesion, bacterial adhesion and bacterial viability. Surface adhesion was evaluated with 3T3 mouse fibroblast cells and two bacterial species. Also, antibacterial activity was evaluated by bacterial viability assay with the two bacterial species. Results showed that the polymer-modified polyvinylchloride surface exhibited significantly decreased 3T3 fibroblast cell adhesion and bacterial adhesion. Furthermore, the modified polyvinylchloride surfaces exhibited significant antibacterial functions by inhibiting bacterial growth with bactericidal activity. Altogether, we have successfully modified the surface of polyvinylchloride using a novel efficient and mild surface coating technique. The first hydrophilic polymer-coated polyvinylchloride surface significantly reduced cell adhesion as well as adhesion of three bacterial species. The second hydrophilic and antibacterial polymer-coated polyvinylchloride surface demonstrated significant antibacterial functions by inhibiting bacterial growth and killing bacteria in addition to significantly reduced 3T3 fibroblasts and bacterial adhesions

Partially Demineralized Macroporous (PDM) Allografts for Cranial Tissue Engineering

poster abstractDecompressive Craniectomy is a cranial surgery where a large part of the cranial bone is removed in order to mitigate swelling in the brain tissue. Consequently, a scaffold biomaterial is required to substitute the lost bone. Ideal cranioplasty biomaterials should have the following features: fit the cranial defect and achieve complete closure, radiolucency, resistance to infections, no dilation with heat, resistance to biomechanical wear, pliability, and inexpensive. Partially Demineralized Macroporous (PDM) allografts exhibit such properties to correct these cranial defects. The main objectives of this study include: (1) examining the effects of demineralization and macroporosity formations on the mechanical and biological properties of allograft bone disks; (2) conducting finite element analysis (FEA) to stimulate the mechanical properties of the PDM allografts; and (3) evaluating the in vitro response of the PDM allografts utilizing pre-osteoblast cell lines. Tibias were harvested from Ossabaw mini-pigs and cylindrical cortical bone sections of 2 mm in thickness and 8 mm in diameter were obtained. Macropores of 600 micrometers in diameter were created to generate porosity levels of 0-40% in the bone disks. The bone disks were then demineralized in 14-wt% EDTA for 6 to 48 hours at 37℃. The relative stiffness was determined for each class using a material testing machine with a loading rate of 1 mm/min using a piston-on-ring set up. To analyze the deformation characteristics, FEA software LS-DYNA was employed. In order to understand the in vitro response, biocompatibility of PDM scaffolds were evaluated by culturing MC3T3-E1 cell lines where XTT and ALP assays were conducted. PDM allografts display the suitable stiffness required for cranial defects. The PDM allograft scaffolds aid in osteogenic proliferation and differentiation of pre-osteoblast cell lines in vitro. However, there will be further in vivo testing regarding the validity of PDM allografts in rat cranial defects. Mentor: Tien-Min Gabriel Chu, Department of Restorative DentistryDecompressive Craniectomy is a cranial surgery where a large part of the cranial bone is removed in order to mitigate swelling in the brain tissue. Consequently, a scaffold biomaterial is required to substitute the lost bone. Ideal cranioplasty biomaterials should have the following features: fit the cranial defect and achieve complete closure, radiolucency, resistance to infections, no dilation with heat, resistance to biomechanical wear, pliability, and inexpensive. Partially Demineralized Macroporous (PDM) allografts exhibit such properties to correct these cranial defects. The main objectives of this study include: (1) examining the effects of demineralization and macroporosity formations on the mechanical and biological properties of allograft bone disks; (2) conducting finite element analysis (FEA) to stimulate the mechanical properties of the PDM allografts; and (3) evaluating the in vitro response of the PDM allografts utilizing pre-osteoblast cell lines. Tibias were harvested from Ossabaw mini-pigs and cylindrical cortical bone sections of 2 mm in thickness and 8 mm in diameter were obtained. Macropores of 600 micrometers in diameter were created to generate porosity levels of 0-40% in the bone disks. The bone disks were then demineralized in 14-wt% EDTA for 6 to 48 hours at 37℃. The relative stiffness was determined for each class using a material testing machine with a loading rate of 1 mm/min using a piston-on-ring set up. To analyze the deformation characteristics, FEA software LS-DYNA was employed. In order to understand the in vitro response, biocompatibility of PDM scaffolds were evaluated by culturing MC3T3-E1 cell lines where XTT and ALP assays were conducted. PDM allografts display the suitable stiffness required for cranial defects. The PDM allograft scaffolds aid in osteogenic proliferation and differentiation of pre-osteoblast cell lines in vitro. However, there will be further in vivo testing regarding the validity of PDM allografts in rat cranial defects

Polyurethane coated with polyvinylpyrrolidones via triazole links for enhanced surface fouling resistance

Surfaces with hydrophilic and antimicrobial properties are very attractive for cardiovascular device-associated applications. The aim of this study was to prepare and coat a hydrophilic polymer containing a functional group capable of forming triazole functionality onto the surface of polyurethane (PU). The modified surfaces were assessed with cell adhesion, bacterial adhesion and bacterial viability. Mouse fibroblast cells (NIH-3T3) and three bacterial species were used for assessment. The results showed that the modified surface not only exhibited a significant reduction in cell adhesion with a 25%–59% decrease to mouse fibroblast but also showed a significant reduction in bacterial attachment with 26%–67%, 24%–61% and 23%–57% decrease to Staphylococcus aureus, Escherichia coli and Pseudomonas aeruginosa, respectively, as compared with original PU. Furthermore, the polymer-modified surface exhibited a significant antibacterial function by inhibiting bacterial growth with reduction of 49%–84%, 44%–79% and 53%–79% to S. aureus, E. coli and P. aeruginosa, respectively, as compared with original PU. These results indicate that covalent polymer attachment enhanced the antibacterial and antifouling properties of the PU surface

Teacher-student rapport and gamified learning: Investigating the role of interpersonal variables in classroom integration

Using the educational setting of Jordan, this research aims to investigate the complex relationship between teacher-student rapport and student involvement in gamified learning experiences. As it relates to the effective use of gamified learning methodologies, this research digs into the far-reaching ramifications of cultivating strong interpersonal interactions between instructors and students. This research uses a strict quantitative technique to investigate the complex relationships between 400 children and 40 teachers. This study's results shed light on an interesting and statistically significant phenomenon: a significant positive connection (r = 0.742, p 0.001) between teacher-student rapport and the amount of engagement seen in gamified learning sessions. The finding, in line with Jordan's educational reforms, highlights the critical role of positive rapport in generating dynamic and significant participation within modern instructional techniques. The practical repercussions highlight the need for teachers to work to improve their interpersonal skills. It becomes clear that this is a crucial factor in enabling effective teaching and learning, especially within the context of contemporary pedagogical approaches. The current research helps us better understand the complex dynamics at play in teacher-student relationships, illuminating their far-reaching consequences for the pursuit of educational excellence in the Jordann setting

Polyvinylchloride surface modified with polymer brushes for reduced protein, cell and bacteria attachment

Abstract The objective of this study was to coat negatively charged polymer brushes by a covalent bond onto the surface of polyvinylchloride using a simple conventional surface free radical polymerisation technique. The coated surfaces were assessed with contact angle, protein adsorption, cell adhesion, and bacterial adhesion. Bovine serum albumin and bovine fibrinogen were used for protein adsorption evaluation. Mouse fibroblast (NIH‐3T3) cells and Pseudomonas aeruginosa were used to assess surface adhesion. Results show that the surface modified with all the attached polymers exhibited significantly reduced contact angle, protein adsorption, and cell as well as bacterial adhesion among which the negatively charged polymers showed extremely low values in all the tests. The negatively charged polymer shows its contact angle at 5° as compared to 70° for original polyvinylchloride. Its bovine serum albumin, bovine fibrinogen, 3T3 adhesion, and P. aeruginosa adhesion were 93%, 84%, 92%, and 92% lower than the original PVC, respectively. Furthermore, the polyvinylchloride surface coated with negatively charged polymer brushes exhibited a hydrogel‐like property. The results indicate that coating a polyvinylchloride surface with acrylic acids using a simple surface‐initiated free radical polymerisation and then converting those to negatively charged salts can be an effective and efficient route for fouling‐resistant applications