scholarly journals Injection-type Denture Base Materials Surface Modification after Vapor Plasma Deposition

2021 ◽  
Vol 58 (2) ◽  
pp. 1-7
Author(s):  
Titus Alexandru Farcasiu ◽  
Daniela Ioana Tarlungeanu ◽  
Gabriela Ciavoi ◽  
Liana Todor ◽  
Magdalena Natalia Dina ◽  
...  

The purpose of this study was to investigate changes of superficial topography and wettability of two injection-type denture base materials following low pressure plasma treatment. Samples of denture base materials (Polyan and Biodentaplast) were fabricate using dedicated technology and were exposed to plasma treatment. Resin surface topography and rugosity were evaluated using SEM and AFM, while wettability was determined through contact angle measurements. Artificial saliva was the testing liquid. Initial contact angles for the two materials are close (Biodentaplast-37.60�, Polyan-36.75�). Plasma treatment halves the values of the contact angle. 30-days measurement reveals a reduced bounce-back effect (Biodentaplast-20.68�, Polyan-20.11�). Surface topography modified differently for the two materials. Rugosity increased significantly for both materials (p[0.05). Surface rugosity values pre- and post-plasma treatment respect the biological threshold of fungal adhesion. Plasma exposure increased injection-type denture base materials wettability with artificial saliva and surface roughness. Injection-type denture base materials and artificial saliva can enhance prosthetic experience of xerostomic patients.

2016 ◽  
Vol 695 ◽  
pp. 91-95
Author(s):  
Alexandru Titus Farcașiu ◽  
Iulian Antoniac ◽  
Aurora Antoniac ◽  
Cătălina Farcașiu

Removable dentures aim to improve masticatory function, esthetics and phonetics. Different materials have been used as denture base materials but poly(methyl methacrylate) (PMMA) is most frequently used in most countries. Surface related properties of denture base materials (roughness, surface free energy, wettability, hydrophobicity, etc.) are of clinical importance since they affect plaque accumulation and staining. Surface roughness specifically influences the adhesion and retention of Candida Albicaans, which has a particular importance in denture-induced stomatitis pathogenesis. Bacterial plaque retention directly affects oral hygiene even if the patient achieves an appropriate cleaning of the denture. Ideally, denture base materials should be smooth so plaque adherence is reduced or even avoided. Test specimens of four heat polymerized materials were obtained by a classical press-pack dough molding technique of 1.5 mm thick wax-plate flasked in class III Moldano followed by the recommended polymerization regime. One of the materials was processed through a fast polymerization cycle. Injection-type materials were automatically produced using a dedicated injection unit. All plates were sectioned in 10 mm x 10 mm samples. No finishing protocol was applied. The selected specimens were examined under field emission scanning electron microscope (SEM). A large variation of surface topography was recorded between materials. There were visual differences between the four heat polymerized resins but also between the two injection-type materials. Surface topography was also influenced by the polymerization regime. Within the limitations of our study, we found that surface topography is influenced by the chemical composition of each material, the heat cure cycle and the processing method.


Forests ◽  
2020 ◽  
Vol 11 (12) ◽  
pp. 1293
Author(s):  
Xuehua Wang ◽  
Kenneth J. Cheng

The inner and outer surfaces of bamboo stems are usually removed prior to the manufacture of bamboo panels because the surfaces are hydrophobic and difficult to bond with glue. Hence, the recovery and utilization ratio of bamboo during processing is low. This study focused on using glow-discharge plasma to treat green bamboo surfaces to make them less hydrophobic. The effects of plasma treatment on green bamboo stems were examined using contact goniometry (wettability), non-contact confocal profilometry and scanning electron microscopy (SEM). Confocal profilometry and SEM revealed that the morphology of green bamboo surfaces varied between 3 different stems. Plasma was able to etch bamboo green surfaces, and make them rougher and more powdery. Plasma treatment was effective at converting green bamboo surfaces from hydrophobic (initial contact angle >110°) to hydrophilic (contact angle <20°). However, this effect was temporary and contact angle increased with time and recovered approximately 30% of its original value after 24 h. Based on our findings, we conclude that plasma treatment can alter parameters such as surface energy and roughness that could improve glue bonding of green bamboo, but delays between plasma treatment and further processing would need to be minimized.


2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Samed Ayhan Özsoy ◽  
Safiye Meriç Acıkel ◽  
Cem Aydemir

Purpose The surface energy of the printing material can be increased to desired levels with different chemicals or methods. However, the important thing is that the surface properties of printing material are not affected negatively. In this way the aim of this paper provide that the surface properties of matte and glossy coated paper is improved by the argon containing atmospheric pressure plasma device because the plasma treatment method does not occur surface damaging on the papers. Design/methodology/approach In experimental studies, test samples cut from 160 mm × 30 mm in size from 115 g/m2 gloss- and matt-coated papers were used. The plasma treatments of paper samples were carried out with an argon containing atmospheric pressure plasma device of laboratory scale that produces plasma of the corona discharge type at radio frequency. The optimized plasma parameters were at a frequency of 20 kHz and plasma power 200 W. A copper electrode of length 12 cm and diameter 2.5 mm was placed in the centre of the nozzle. Findings Research findings showed that the surface energies of the papers increased with the increase in plasma application time. While the contact angle of the untreated glossy paper is 82.2, 8 second plasma applied G3 sample showed 54 contact angle value. Similarly, the contact angle of the base paper of matt coated is 91.1, while M3 is reduced to 60.4 contact angles by the increasing plasma time. Originality/value Plasma treatment has shown that no chemical coating is needed to increase the wettability of the paper surface by reducing the contact angle between the paper and the water droplet. In addition, the surface energies of all papers treated by argon gas containing atmospheric pressure plasma, increased. Plasma treatment provides to improve both the wettability of the paper and the adhesion property required for the ink, with an environmentally friendly approach.


1989 ◽  
Vol 5 (6) ◽  
pp. 399-402 ◽  
Author(s):  
M.A.S. Al-Mulla ◽  
W.M. Murphy ◽  
R. Huggett ◽  
S.C. Brooks

2008 ◽  
Vol 55-57 ◽  
pp. 753-756 ◽  
Author(s):  
R. Nakhowong ◽  
Toemsak Srikhirin ◽  
Tanakorn Osotchan

The surface of polystyrene (PS) thin films in argon plasma was modified to study the hydrophilicity properties. An inductively coupled plasma (ICP) system was used to generate the argon plasma. In the experiment, the effect of RF power levels, gas flow rate and treatment time was investigated. The surface morphology of PS films was examined by the atomic force microscopy (AFM), also the contact angle goniometry was used for measuring the wettability of PS films before and after plasma treatment. After the plasma treatment, AFM images of PS revealed the increasing of the surface roughness as increasing the power levels and treatment times. Moreover, after treated with argon plasma, the contact angles of polystyrene films also decrease where the power levels and treatment times were increased. It is clear that the effects of power levels and treatment time improve the wettability of PS films. It can also be observed that by placing the sample in air after plasma treatment, the contact angle gradually increases probably due to moisture absorption in the PS films.


2007 ◽  
Vol 14 (04) ◽  
pp. 821-825 ◽  
Author(s):  
Q. F. WEI ◽  
Y. LIU ◽  
F. L. HUANG ◽  
S. H. HONG

Polytetrafluoroethylene (PTFE) has been increasingly used in many industries due to its low frictional coefficient and excellent chemical inertness. The surface properties of PTFE are of importance in various applications. The surface properties of PTFE can be modified by different techniques. In this study, PTFE film was treated in oxygen plasma for improving surface wettability. The effects of plasma treatment on dynamic wetting behavior were characterized using Scanning Probe Microscopy (SPM), Fourier transform infrared spectroscopy (FTIR), and dynamic contact angle (DCA) measurements. SPM observations revealed the etching effect of the plasma treatment on the film. The introduction of hydrophilic groups by plasma treatment was detected by FTIR. The roughened and functionalized surface resulted in the change in both advancing and receding contact angles. Advancing and receding contact angles were significantly reduced, but the contact angle hysteresis was obviously increased after plasma treatment.


1995 ◽  
Vol 386 ◽  
Author(s):  
A. Philipossian ◽  
M. Moinpour ◽  
R. Wilkinson ◽  
V. H. C. Watt

ABSTRACTRemoving the native oxide from the poly-Si surface prior to WSix deposition is essential for achieving high quality silicides as well as sufficient film adhesion, particularly after high temperature anneal or oxidation. Contact angle studies have been used to determine initial and time-dependent surface characteristics of several types of silicon surfaces following immersions in HF-based etchants for varying amounts of time. The morphological characteristics of the surfaces before and after exposure to etchants, as well as the relative etch rates and wetting capabilities of the etchants have been used to explain the following results: With respect to initial contact angle studies, the implanted & annealed polycrystalline silicon surface has the lowest contact angle followed by polycrystalline and monocrystalline surfaces. Longer immersion times yield lower initial contact angles. The 0.1% lightly-buffered HF solution results in the highest contact angle followed by the 1% buffered HF solution with surfactant, and the 1% HF solution. With respect to contact angle changes during ambient air exposure time, the asdeposited polycrystalline silicon surface is most stable followed by monocrystalline, and implanted & annealed polycrystalline silicon surfaces. Longer immersion times improve surface stability while the 0.1% lightly-buffered HF solution results in the most stable surface followed by the 1% buffered HF solution with surfactant, and the 1% HF solution.


Author(s):  
Teng Wang ◽  
Yi Wan ◽  
Zhaojun Kou ◽  
Yukui Cai ◽  
Bing Wang ◽  
...  

The surface topography and wettability are important factors that determine the biocompatibility of biomaterials. In this article, the hierarchical micro/nano-topography of titanium alloy surface was fabricated by micro-milling and alkali-hydrothermal reaction. The surface topography and chemical composition of treated surfaces were characterized using laser scanning microscope and scanning electron microscope. The contact angles of surfaces with different micro/nano-topographies were measured by contact angle tester. MC3T3s morphology and osteocalcin productions were characterized to investigate the influence of surface modification on implants’ biocompatibility. The results show that hydrophilicity of micro-structured surface decreased compared to the untextured surface and contact angle values decreased with the increase in micro-groove spacing in small increments. In addition, the surfaces treated with alkali-hydrothermal reaction displayed strong hydrophilicity and the surface energy increased by 40 nJ/cm2 approximately. In vitro tests indicated that micro/nano-structured surface improved the adhesion, spreading, and differentiation of MC3T3s.


1980 ◽  
Vol 8 (2) ◽  
pp. 102-108 ◽  
Author(s):  
Bryan Ellis ◽  
Souza A.A. Faraj

Author(s):  
Rajesh Leeladhar ◽  
Wei Xu ◽  
Chang-Hwan Choi

In this paper, we experimentally studied the evaporative behavior of the nanofluid droplets (fluid containing metal nanoparticles) on nanoporous superhydrophobic surfaces. Uniformly dispersed in water, gold chloride (AuCl3) nanoparticles of varying sizes (10–250 nm) and concentrations (0.001–0.1% wt) were tested as nanofluids. Porous anodized aluminum oxide (AAO) with a pore size of 250 nm was tested as a nanoporous superhydrophobic surface, coated by a self assembled monolayer (SAM). During the evaporation in a room temperature and pressure, the evaporation kinetics (e.g., contact angle, contact diameter, and volume) of the nanofluid droplets was measured over time by using a goniometer. In the beginning, the initial droplet contact angles were significantly affected by the nanoparticle sizes and concentrations such that as the concentration increased, the initial contact angle decreased, which was more pronounced at larger particle sizes. During evaporation, despite the different particle sizes and concentrations, there were two distinct stages shown, especially for the change of contact angles, i.e., gradual decrease in the beginning, followed by rapid decrease in the end. No remarkable wetting transition from de-wetting (Cassie) to wetting (Wenzel) state was shown during the evaporation. Evaporation rate was influenced by nanoparticles such that it was significantly mitigated with the nanofluid droplet of the highest concentration (0.1% wt). The scanning electron microscope (SEM) images show that the ring-like dry-out pattern forms after the evaporation of nanofluids with lower concentrations (0.001%, 0.01% wt), whereas the one with higher concentrations (0.1%wt) forms a uniformly distributed pattern. These results demonstrate that nanoparticle sizes and concentrations make significant effects on interfacial phenomena in droplet evaporation on nanostructured surfaces, which will impact many engineering applications and system designs based on droplets such as microfluidics and heat transfer.


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