Biocompatibility of Ar plasma-treated fluorinated ethylene propylene: Adhesion and viability of human keratinocytes

Temporal Changes in the Surface Chemistry and Topography of Reactive Ion Plasma-Treated Poly(vinyl alcohol) Alter Endothelialization Potential

Synthetic small-diameter vascular grafts (<6 mm) are used in the treatment of cardiovascular diseases, including coronary artery disease, but fail much more readily than similar grafts made from autologous vascular tissue. A promising approach to improve the patency rates of synthetic vascular grafts is to promote the adhesion of endothelial cells to the luminal surface of the graft. In this study, we characterized the surface chemical and topographic changes imparted on poly(vinyl alcohol) (PVA), an emerging hydrogel vascular graft material, after exposure to various reactive ion plasma (RIP) surface treatments, how these changes dissipate after storage in a sealed environment at standard temperature and pressure, and the effect of these changes on the adhesion of endothelial colony-forming cells (ECFCs). We showed that RIP treatments including O2, N2, or Ar at two radiofrequency powers, 50 and 100 W, improved ECFC adhesion compared to untreated PVA and to different degrees for each RIP treatment, but that the topographic and chemical changes responsible for the increased cell affinity dissipate in samples treated and allowed to age for 230 days. We characterized the effect of aging on RIP-treated PVA using an assay to quantify ECFCs on RIP-treated PVA 48 h after seeding, atomic force microscopy to probe surface topography, scanning electron microscopy to visualize surface modifications, and X-ray photoelectron spectroscopy to investigate surface chemistry. Our results show that after treatment at higher RF powers, the surface exhibits increased roughness and greater levels of charged nitrogen species across all precursor gases and that these surface modifications are beneficial for the attachment of ECFCs. This study is important for our understanding of the stability of surface modifications used to promote the adhesion of vascular cells such as ECFCs.

Biocompatibility and Antibiofilm Properties of Calcium Silicate-Based Cements: An In Vitro Evaluation and Report of Two Clinical Cases

Simple Summary

Calcium silicate-based cements are successfully applied in the different fields of endodontics and vital pulp therapy. To better assess the properties of these bioactive materials, the present in vitro and in vivo study aimed to compare the biocompatibility and antibiofilm properties of ProRoot MTA and Biodentine. Human osteogenic sarcoma (Saos-2) cells were cultured in the presence of both materials and evaluated. Moreover, the bioactive cements were in vivo applied to perform vital pulp therapy on immature permanent teeth affected by reversible pulpitis. Saos-2 cells’ viability was slightly greater in the presence of ProRootMTA than Biodentine and cells would grow in a better way on ProRootMTA disks than on Biodentine ones. Moreover, ProRootMTA showed a powerful antibiofilm effect towards Streptococcus mutans. The in vitro results were clinically supported by a 100% success rate after 2 years of follow-up.

Abstract

Calcium silicate-based cements have reached excellent levels of performance in endodontics, providing predictable and successful results. To better assess the properties of these bioactive materials, the present study aimed to compare the biocompatibility and antibiofilm properties of ProRoot MTA and Biodentine. Human osteogenic sarcoma (Saos-2) cells were cultured on ProRoot MTA and Biodentine samples or in the presence of both cement extracts. Cell viability assay, measurement of reactive oxygen species (ROS), immunofluorescence analysis, as well as morphological evaluations were conducted. Moreover, Streptococcus mutans was used to assess the biofilm forming ability on ProRoot MTA and Biodentine disks. Finally, both cements were applied in vivo to treat immature permanent teeth affected by reversible pulpitis. Results: Cell viability assay demonstrated that Saos-2 cells had a dose- and time-dependent cytotoxicity to both analyzed cements, although cells exposed to ProRoot MTA showed a better cell vitality than those exposed to Biodentine (p < 0.001). Both cements demonstrated ROS production while this was greater in the case of Biodentine than ProRoot MTA (p < 0.001). Immunofluorescence images of the cytoskeleton and focal adhesions showed no differences in Saos-2 cells grown in the presence of ProRoot MTA eluate; whereas in the Biodentine groups, cells showed a morphology and focal adhesions more similar to that of the control sample, as the eluate concentration decreased. Morphological analysis revealed that Saos-2 cells were more flattened and exhibited better spreading when attached to ProRoot MTA disks than to Biodentine ones. The antibiofilm properties showed a time-dependent powerful inhibition of S. mutans superficial colonization and an antibiofilm effect of both cements. Clinically, complete root formation of the treated elements was achieved using the two studied cements, showing stable results over time. ProRoot MTA and Biodentine was demonstrated to be biocompatible and to possess antibiofilm properties. Their clinical application in vital pulp therapy provided successful outcomes after 2 years of follow-up.

Utilizing Radio Frequency Plasma Treatment to Modify Polymeric Materials for Biomedical Applications

Studies that utilize radio frequency plasma modification as a strategy to tune the surface properties of polymeric constructs with the goal of enhancing their use as biomedical devices have grown considerably in number over the past decade. In this Review, we present the importance of plasma surface treatment to biomedical applications, including tissue engineering and wound healing. First, we introduce several key polymeric materials of interest for use as biomaterials, including those that are naturally derived and synthetic. We, then, provide an overview of possible outcomes of plasma modification, such as surface activation, etching, and deposition of a thin film, all of which can be used to alter the surface properties of a given polymer. Following this discussion, we review the methods used to characterize plasma-treated polymer surface properties, as well as the techniques used to evaluate their interactions with biological species of interest such as mammalian cells, bacteria, and blood components. To close, we provide a perspective on future outlooks of this exciting and rapidly evolving field.

Cell Behavior of Primary Fibroblasts and Osteoblasts on Plasma-Treated Fluorinated Polymer Coated with Honeycomb Polystyrene

The development of new biocompatible polymer substrates is still of interest to many research teams. We aimed to combine a plasma treatment of fluorinated ethylene propylene (FEP) substrate with a technique of improved phase separation. Plasma exposure served for substrate activation and modification of surface properties, such as roughness, chemistry, and wettability. The treated FEP substrate was applied for the growth of a honeycomb-like pattern from polystyrene solution. The properties of the pattern strongly depended on the primary plasma exposure of the FEP substrate. The physico-chemical properties such as changes of the surface chemistry, wettability, and morphology of the prepared pattern were determined. The cell response of primary fibroblasts and osteoblasts was studied on a honeycomb pattern. The prepared honeycomb-like pattern from polystyrene showed an increase in cell viability and a positive effect on cell adhesion and proliferation for both primary fibroblasts and osteoblasts.

Argon plasma-treated fluorinated ethylene propylene: Growth of primary dermal fibroblasts and mesenchymal stem cells

Surface modification is an important step in making a synthetic polymer cytocompatible. We have previously reported improved cytocompatibility of immortalized human keratinocytes (HaCaT) with the otherwise bioinert fluorinated ethylene propylene (FEP) upon treatment with argon plasma discharge. In this article, we show that FEP modified with Ar plasma with the power of 3 and 8 W for 40 and 240 s served as a suitable material for cultivation of primary human dermal fibroblasts (HDF), which showed significantly improved proliferation and spreading comparable to standard tissue culture polystyrene. We also evaluated focal adhesions formed by HDF cells on modified FEP, which were far more numerous compared to pristine FEP. Moreover, we attempted spontaneous osteogenic differentiation of adipose-derived mesenchymal stem cells modified with human telomerase reverse transcriptase on Ar plasma-modified FEP. While the spontaneous osteogenic differentiation was unsuccessful, the cells were able to adhere and differentiated on tested matrices upon the administration of osteodifferentiation medium. These combined findings suggest that the treatment of FEP with Ar plasma comprises and efficient method to enable the adhesion and proliferation of various cell types on an otherwise largely bioinert material.