Surface Roughness Tester Research Articles

Evaluation of Surface Roughness of Translucent Zirconia After Applying Nd:YAG and CO2 Lasers: An In Vitro Study.

Surface roughness is one of the most important factors that play an important role in increasing the connection between the surface of the tooth and the applied restoration. Due to the increased interest in zirconia and the improvement of its mechanical and aesthetic properties, studies have increased that work to improve and increase its surface roughness so that it can be used as a veneer in the future. This study aims to compare the effect of two types of lasers on the surface of highly transparent zirconia to evaluate the surface roughness resulting from the two techniques. The study sample consisted of 20 ceramic cubes made of translucent zirconia (DD cubeX2, Dental Direct, Germany). It was made using a CAD-CAM Zircodenta device (Imes-Icore, Germany) and a zirconia sintering furnace (Imes-Icore, Germany). The study sample was divided into two groups; the first group consisted of 10 cubes exposed to Nd:YAG laser and the second group consisted of 10 discs exposed to continuous wave CO2 laser. The surface roughness test was conducted for the study samplesin each of the groups using a surface roughness tester. Data were collected and analyzed using SPSS v25 software. The surface roughness was measured and its mean was 1.208±0.22in the Nd:YAG laser group and 0.809±0.21in the CO2laser group. There was a significant difference between the study groups according to the independent sample T-test. This study concluded that the Nd:YAG laser surface roughensof zirconia isgreaterthan the continuous wave CO2 laser, with a substantially significant difference.

Optimization of tool wear and surface roughness in ST-37 steel turning process with varying tool angles and machining parameters

The process of cutting low carbon steel (ST-37) typically utilizes High-Speed Steel (HSS) tools owing to their high hardness, affordability, and ease of shaping tool geometry. In machining, tool geometry plays a crucial role in the material cutting process and determines the quality of the final product, particularly surface roughness. The objective of this research is to achieve optimal surface roughness by varying the tool geometry and nose radius. This study employed an experimental approach using ST-37 and HSS tools. The variations in tool geometry include side rake angles of 12°, 15°, and 18°; side cutting edge angles of 85°, 80°, and 75°; and nose radii of 0 mm, 0.4 mm, and 0.8 mm. The machining parameters applied consist of a cutting depth of 1 mm and 2 mm, spindle rotation speeds of 185 rpm, 425 rpm, and 624 rpm, and a feed rate of 0.05 mm/rev, 0.075 mm/rev, and 0.1 mm/rev. Tool wear measurements were captured using a USB camera, whereas the surface roughness was assessed using a surface roughness tester. The impact of the tool geometry on the surface roughness was analyzed using the Taguchi-Grey Relational Analysis (Taguchi-GRA) and ANOVA methods. The optimal combination for ST-37 lathe machining with a sharpening tool is: A1 (cutting depth 1 mm), B1 (cutting speed 17.42 m/min), C3 (feed 0.05 mm/rev), D1 (corner radius 0 mm), E3 (side rake angle γ 18°), and F3 (side cutting edge angle γ 75°). According to the Analysis of Variance (ANOVA), three factors—cutting speed, tool tip angle, and chip angle—should be considered to achieve minimal tool wear and desirable surface roughness during machining

Study the Structure and Properties of Antibacterial TiO2/HAP Coating onto Ti Alloy Using Electrophoretic Deposition Technique for Biomedical Application

In the present study, single layer, titanium dioxide (TiO2) and TiO2/HAP nano-particles coatings were fabricated by electrophoretic deposition on titanium alloy Ti-6Al-4V. As a result of accidents, diseases and other causes, efforts and research are continued to reach results closest. The damaged that occur to some of them in the living of the organism in general and the human being in particular, this can be done throughout the existing the implantation of medical minerals, ligaments of bones, teeth and other parts that compensate. Through science, opportunities and experiments have been provided to obtain satisfactory results in terms of the biocompatibility of titanium alloy Ti-6Al-4V implants and their alloys, which are classified as one of the best biocompatible materials within vivo tissues. This study aims to increase improve this alloy antibacterial properties by coating the surface with a bio ceramic (TiO2 and TiO2/HAP) nano-powders. were made on titanium alloy Ti-6Al-4V substrate using an electrophoretic deposition (EPD) technique, charged particles suspended in ethanol at a concentration of 50 g/L, for each powder with ideal conditions of 20V and a deposition time of (4 min). The surface characteristics of coated substrates, such as micro-hardness, surface roughness and wettability antibacterial test were evaluated and compared to that of the uncoated substrates. The results showed that the EPD is a promising technique to create a bio coating on titanium alloy Ti-6Al-4V substrate with outstanding structure and properties for biomedical applications. The results demonstrated that the coated sample under coating conditions (20V, 4min) which is close to the ratio found in living bone. The results also of the wettability test showed that the contact angle of the deposited paint is 5.9 degrees, and this positive result is useful for biomedical applications and proved that the coating is hydrophilic.

Impact of surface treatment and addition of CuO NPs of surface roughness of acrylic denture base bonded to soft liner

Background: The import of the rough surface makes the application of several elements to enhance this feature vital for the adhesion of soft liners. Aim: The study's goal was to to ascertain the impact of copper oxide nanoparticles added in two ratios to heated-cured acrylic resin and fiber laser surface treatment on surface roughness. Materials and methods:60 acrylic specimens in the shape of discs were manufactured and divided into three groups: one received no addition; the other two received the addition of 0.3% CuO NPs; and a third group that received the addition of 0.5% CuO NPs. Each group was divided into two categories: those that were laser treatment and those who did not. The surface roughness test was then examined using a roughness tester called a profilometer. Results: The average roughness values were high for the control groups and low for the CuO NPs 0.5% groups. The mean values in the laser-treated groups had greater roughness than the control groups, according to the laser application.Conclusion:. As the fraction of CuO NPs increased, the surface roughness reduced. The laser treatment also reduced surface roughness.

Surface Finish Optimization of Vapor Smoothened PLA Fabricated Parts with Microstructural Analysis

Additive Manufacturing (AM) is a product creation method done layer-by-layer. This process tends to create an unwanted feature known as staircase effect. Vapor smoothing is considered a viable solution for polymer-based AM products to minimized surface roughness. Research literature concerning vapor smoothing of polylactic acid (PLA) parts generally limited unlike its ABS counterpart. This research aims to identify optimum level for both chamber temperature and exposure time of the AM product. Two methods were used to compare their outputs with one another. The two methods are surface roughness tester and optical microscopy. The results provided an impressive 50.88 and 62.72% improvement based on the two test methods. Lastly, a contour-plot was generated to provide future users a guideline if they want to conduct research similar study.

Study the Structure and Properties of TiO<sub>2</sub>/HAp Coating onto Ti-6Al-4V Alloy Using Electrophoretic Deposition

In the present study, (TiO2/HAP) and TiO2 coatings were fabricated with electrophoreticdeposition on substrate for titanium alloy. This study aims to increase improve this alloyantibacterial properties by coating the surface with a bio ceramic (TiO2 and TiO2/HAP)nano-powders. Coating on Ti-6Al-4V with an electrophoretic deposition(EPD) technique,ideal conditions of 20V and a deposition time of (4 min). The surface properties of coatedsubstrates, such as, micro-hardness, surface roughness and wettability antibacterial test wereevaluated and compared to that of the uncoated substrate. The results showed that theelectrophoretic deposition is a favorable technique to make a bio coating on Ti-6Al-4Vsubstrate with excellent properties and structure for applications biomedical.The average micro-hardness of the TiO2/HAP coated sample is 1024 HV compared withthat of uncoated substrates is 80 HV. The average thickness of TiO2/HAP coating isdetermined to be (18µm) on the substrate surface at factor deposition time (4 min). The resultsof previous research indicate that the high wettability and surface roughness at the micronscale were for the synergistic effect of reduction on cell adhesion and growth.

Optimization of Antibacterial properties of 316 Austenitic Stainless Steel

In the present study, titanium dioxide (TiO2/Chitosan) nano-particles layer coatings were fabricated by electrophoretic deposition on 316 Austenitic Stainless steel substrate. Aims to enhance antibacterial properties by coating the surface with a bio ceramic (TiO2) nano-powders. TiO2, were made on 316 austenitic stainless steel substrate with an EPD (electrophoretic deposition) technique, charged particles suspended in ethanol at a concentration of 50 g/L, for each powder with ideal conditions of 20V and a deposition time of (2, 4 and 6 min). The surface tests of coated substrates, such as, micro-hardness, surface roughness and wettability antibacterial test were evaluated and compared to that of the uncoated substrates. The showed results the electrophoretic deposition is a favorable technique to make a bio coating on 316 Austenitic Stainless steel substrate with excellent properties and structure for applications biomedical. The results demonstrated that the coated sample under coating conditions (20V, 2min) which is close to the ratio found in living bone. the average micro-hardness of the TiO2 coated sample is 1483 HV compared with that of uncoated substrates is 460 HV. The results also of the wettability test showed that the contact angle of the deposited paint is 5.9 degrees, and this positive result is useful for biomedical applications and proved that the coating is hydrophilic.

Influence of bottled salad dressings on the development of enamel erosion in the presence or absence of salivary pellicle – An in vitro study

BackgroundAcidic beverages are believed to elevate the risk of enamel surface erosion. In addition to the intake of soft drinks, the increased consumption of salad dressings has been linked to a higher prevalence of dental erosion. Therefore, the current study aimed to investigate the influence of bottled salad dressings on the development of enamel erosion in the presence or absence of pellicle through in vitro experiment. MethodsPreliminary pH and calcium analyses of solutions were performed. Highest pH and calcium content was found for sandwich spread i.e., 4.69 and 55.4 mg/100 g grams, respectively. Eighty tooth specimens (measuring 4 × 4 × 3 mm) were prepared from extracted human premolars and randomly assigned to four groups (group 1: orange juice; group 2: eggless plain mayonnaise; group 3: sandwich spread; and group 4: thousand island dressing) with 20 samples in each group. Ten tooth specimens from each group were immersed in 20 ml of the respective solutions for 5 min (control group). The remaining ten tooth specimens from each group were submerged in 5 mL saliva vials for 3 min to facilitate salivary pellicle formation before being immersed in their respective solutions for 5 min (saliva-covered group). Pre and post-experimental assessments of enamel roughness and hardness were conducted using a surface roughness tester and Knoop Hardness indenter, respectively. ResultsOverall, enamel roughness was notably elevated in the control group, with the eggless plain mayonnaise (0.52 ± 0.38) and thousand island dressing groups (0.57 ± 0.29) showing a significant increase in surface roughness post-test (p = 0.05). Nevertheless, there was no significant difference in the enamel roughness between the groups. On the other hand, regardless of the presence/absence of the salivary pellicle, a marked decrease in enamel hardness was observed among all groups except for group 3 (sandwich spread) with a mean score of 311.5 ± 82.6 (p < 0.05). ConclusionA significant increase in surface roughness and reduction in enamel hardness was observed with salad dressings. However, in vitro formed salivary pellicle showed a protective effect against tooth erosion.

Potential of Avocado Seed Extract (Pasea Americana) As A Corrosion Inhibitor Against Surface Roughness OF CUNITI Orthodontic WIRE

The surface roughness of orthodontic archwires is an essential factor that deter- mines the effectiveness of arch-guided tooth movement. CuNiTi-based wires are widely used in orthodontic treatment, but the oral environment can trigger corrosion of CuNiTi orthodontic wires. The tannin content in avocado seed extract can be used as a corrosion inhibitor through two working mechanisms, namely, forming a passive layer and an adsorption process. The aim of this research is to examine the effect of avocado seed extract as a corrosion inhibitor on the surface roughness of orthodontic CuNiTi wire. The as- retacngular 17 x 25 inch CuNiTi wire were taken in 4 group (1 control group soaked in artificial saliva and 3 treatment groups soaked in avocado seed extract ). Samples were immersed in avocado seed extract with concentrations of 1,5 g/L, 2 g/L and 2,5g/L for 7 days. For surface roughness was test Surface Roughness Average analysis. One way ANOVA test showed that there was a significant difference between the control group and all treatment groups in the surface roughness test with a value of p = 0.000. Post Hoc LSD test showed that there were no significant differences between treatment group 2 and treatment group 3 with a p value = 0.122. Providing avocado seed extract with tannin content at concentrations of 1.5 g/L and 2 g/L can reduce surface roughness on CuNiTi wire due to the corrosion process.

Enhancement of titanium surfaces using different acid solutions at room temperature to improve bone cell responses

Background/purposeEarly osseointegration of titanium (Ti) dental implants relies on the surface topography. Surface modification of Ti seeks to enhance bone regeneration around implants. Acid etching is the simple, less technique sensitive and cost-effective technique for surface treatment. The purpose of this study was to elucidate the simplified acid etching technique at room temperature lies in its capacity to enhance both physical properties and biological reactions relevant to bone. Materials and methodsUtilizing sulfuric acid (H2SO4) and hydrochloric acid (HCl), five distinct acid solutions were prepared, and the acid etching process was executed at five different time points at room temperature. The surface characterization of nanoscale modified titanium disks encompassed surface characteristics analysis, wettability and roughness tests. The biocompatibility evaluation involves tests that assess cell attachment, proliferation, alkaline phosphatase activity (ALP), and mineralization. ResultsThe surface modified by HCl exhibited the most significant alterations, characterized by an elevated roughness value and reduced hydrophilicity properties. The surface treated with a mixture of HCl and H2SO4 for 24 h (TH5) displayed a hydrophilic surface and high surface energy. Acid etched surfaces showed the greater cell attachment with long pseudopodia. The cell proliferation rate and ALP reaction rate of TH5 is the highest at day 7. Cells mineralization of Ti surface treated with 37% HCl for 24 h (TC5) shows the lowest and TH5 shows the greatest on day 21. ConclusionThe proposed acid etching at room temperature utilizing a combination of H2SO4 and HCl demonstrated improved physical properties while fostering favorable biological responses.

Effective use of adaptive slicing in binder jetting using Taguchi method and surface roughness measurement with image processing

PurposeThe use of additive manufacturing in many branches of industry is increasing significantly because of its many advantages, such as being able to produce complex parts that cannot be produced by classical methods, using fewer materials, easing the supply chain with on-site production, being able to produce with all kinds of materials and producing lighter parts. The binder jetting technique, one of the additive manufacturing methods researched within the scope of this work, is predicted to be the additive manufacturing method that will grow the most in the next decade, according to many economic reports. Although additive manufacturing methods have many advantages, they can be slower than classical manufacturing methods regarding production speed. For this reason, this study aims to increase the manufacturing speed in the binder jetting method.Design/methodology/approachAdaptive slicing and variable binder amount algorithm (VBAA) were used to increase manufacturing speed in binder jetting. Taguchi method was used to optimize the layer thickness and saturation ratio in VBAA. According to the Taguchi experimental design, 27 samples were produced in nine different conditions, three replicates each. The width of the samples in their raw form was measured. Afterward, the samples were sintered at 1,500 °C for 2 h. After sintering, surface roughness and density tests were performed. Therefore, the methods used have been proven to be successful. In addition, measurement possibilities with image processing were investigated to make surface roughness measurements more accessible and more economical.FindingsAs a result of the tests, the optimum printing condition was decided to be 180–250 µm for layer thickness and 50% for saturation. A separate test sample was then designed to implement adaptive slicing. This test sample was produced in three pieces: adaptive (180–250 µm), thin layer (180 µm) and thick layer (250 µm) with the determined parameters. The roughness values of the adaptive sliced sample and the thin layer sample were similar and better than the thick layer sample. A similar result was obtained using 12.31% fewer layers in the adaptive sample than in the thin layer sample.Originality/valueThe use of adaptive slicing in binder jetting has become more efficient. In this way, it will increase the use of adaptive slicing in binder jetting. In addition, a cheap and straightforward image processing method has been developed to calculate the surface roughness of the parts.

Comparative effects of glazing versus polishing on mechanical, optical, and surface properties of zirconia ceramics with different translucencies.

This study compared the effects of glazing versus polishing on mechanical, optical, and surface properties of zirconia ceramics with different translucencies. In this in vitro study, 120 bar-shaped specimens (25 × 4 × 1.2 mm) were fabricated from three different types of zirconia with different translucencies (n = 40, DD Bio ZW, ZX2, and Cube X2). After sintering, each zirconia group was randomly divided into five subgroups of control (glazing), glazing + bur abrasion, glazing + bur abrasion + polishing with EVE Diacera® kit, glazing + bur abrasion + reglazing, and glazing + bur abrasion + polishing with EVE Diacera® kit + reglazing. The specimens underwent surface roughness, hardness, flexural strength, and translucency tests, as well as X-ray diffraction (XRD) and scanning electron microscopy (SEM) for assessment of surface topography. Data were analyzed by one-way analysis of variance, Tukey test, and Pearson test (α = .05). Flexural strength, surface hardness, and translucency were significantly correlated with zirconia type. ZW zirconia had significantly higher flexural strength and surface hardness and significantly lower translucency than Cube X2 and ZX2 (p < .001). Surface roughness had no significant correlation with zirconia type (p = .274). Polishing created the smoothest, and bur abrasion created the roughest surface (p < .001). Flexural strength and hardness in most experimental groups were significantly lower than in the control group (p < .001). Translucency was not significantly different in bur abrasion and polishing groups, compared with the control group; however, reglazing significantly increased the translucency (p < .001). SEM micrographs confirmed the surface roughness results. XRD showed monoclinic phase only in reglazed groups. Of different surface treatments, polishing improved the surface properties and caused the smallest change in mechanical properties of zirconia with different translucencies.

Wear performance of Ti-based alloy coatings on 316L SS fabricated with the sputtering method: Relevance to biomedical implants.

This investigation was conducted to encapsulate 316L SS with a Ti-based alloy coating. The aim was to fabricate a coating using TiN, TiO2, and TiCoCr powders on 316L SS through the physical vapor deposition (PVD) sputtering process. The powders were consecutively coated on 316L SS through the PVD sputtering process with coating durations of 30, 60, and 90 min. Further microhardness, surface roughness, microabrasion, and adhesion strength tests were also carried out. A 60% improvement in abrasion resistance was observed in TiCoCr-coated samples compared to the uncoated substrate. The X-ray diffraction results confirmed the optimal formation of Ti alloy coatings with corresponding orientation over the SS substrates. Moreover, TiCoCr with a 90 min coating duration had much better surface characteristics than TiO2 and TiN. The 90 min coating duration should be optimal for coating in steel for bio-implants.

In-situ formation of Zn-MOF coating on MgO/HA composite layer produced by plasma electrolytic oxidation on Mg-Sn-Mn-Ca alloy for orthopedic internal fixation devices

ABSTRACT A novel ultra-sound assisted method was used to grow zinc-metal organic framework (Zn-MOF) film on magnesium oxide/hydroxyapatite (MgO/HA) composite layer developed using plasma electrolytic oxidation (PEO) on Mg-5Sn-0.2Mn-0.2Ca alloy. The microstructure surface roughness and microhardness tests were performed on the samples to evaluate the mechanical properties of the coatings. The electrochemical corrosion test was performed to evaluate the corrosion resistance of the coated Mg alloy. Further, an in-vitro bioactivity test was performed to study the biocompatibility and bioactivity of the coated alloy, which is an essential aspect of biomedical applications. Results showed that the MgO/HA composite coating was helpful in the in-situ growth of the Zn-MOF particles by mechanically interlocking them. Further, incorporating hydroxyapatite in the coating could also increase the bioactivity. The study also confirmed that the bi-layer coating of Zn-MOF on the MgO/HA composite layer improved the surface roughness, hardness, biocorrosion resistance, and bioactivity making it more likely to be used for orthopedic internal fixation devices.

Effect of different root canal irrigants on surface roughness and microhardness of Biodentine combined with triple antibiotic paste: An in vitro study

Background: Biodentine is widely used for endodontic applications; recently, it has been incorporated with triple antibiotic paste (TAP). The effect of endodontic irrigants on the physical characteristics of this new combination needs to be studied. Aims: The aim of the study was to evaluate the surface roughness and microhardness of Biodentine incorporated with TAP subjected to various endodontic irrigants. Materials and Methods: Hundred cylindrical discs (6 mm × 3 mm) were prepared by mixing the Biodentine with TAP (3:1). The specimens were subjected to different irrigating solutions for 5 min in 5 groups (n = 20): Group 1: distilled water (control), Group 2: 2.5% sodium hypochlorite, Group 3: 17% ethylenediaminetetraacetic acid, Group 4: 2% chlorhexidine (CHX), and Group 5: 2% chitosan nanoparticles (CSNs). Half of the specimens in each group were subjected to surface roughness (n = 10) and another half to microhardness (n = 10). Surface roughness was measured using a surface roughness tester, and digital Vickers microhardness testing was performed on each specimen. Statistical Analysis: One-way ANOVA and post hoc Tukey’s tests (P ≤ 0.05) were used. Results: The highest microhardness was found with 2% CSN, whereas 2% CSN and 2% CHX had a minimal effect on the surface roughness of Biodentine incorporated with TAP (P ≤ 0.05). Conclusion: The root canal irrigant 2% CSN exhibited the highest microhardness and least surface roughness of modified Biodentine with TAP.

Microstructure and surface morphology change of hydrogenated diamond-like carbon coating with gradient Cr and Si under high temperature and high pressure

A series of annealing treatments were designed to investigate the microstructure structure and surface morphology of hydrogenated diamond-like carbon coating with gradient Cr and Si (DCrSi) in different environments (argon & isostatic pressure) at different temperatures (400°C, 500°C, and 600°C). The pressure effect on the stability of DCrSi coatings was deduced from the analysis of the microstructure structure and surface morphology by using scanning electron microscopy (SEM), surface roughness test, and Raman spectroscopy. The experiment results show that no apparent change to the layer structure can be found in the argon annealed and HIPped coatings. Similar to argon annealed coatings, with increasing HIPping temperature, the surface roughness of coatings increases, and the sp3 content of the coatings reduces. The relatively low roughness of the HIPped surfaces compared with the argon annealed ones could be attributed to the delayed transformation from sp3 carbon bonding to sp2 carbon bonding (i.e., graphitization) by high pressure. Compared with Si-free DCr coating, for Si-containing DCrSi coatings, Si bonded with C from broken C-H bonding and C-C bonding to form SiC quasi compound. Adding silicon into DLC can increase the density of the coatings.

Effect of depositional strategy on surface roughness of Al-5%Mg wall fabricated via Cold Metal Transfer based Wire Arc Additive Manufacturing

Cold Metal Transfer (CMT) based Wire Arc Additive Manufacturing (WAAM) is the future-driven novel technology for fabricating complex metal components, having advantages like high deposition rates, increased material efficiency, lesser lead time, low heat input, and low cost. Despite of above advantages, the CMT-WAAM process possesses few limitations in terms of producing metal components with high geometrical accuracy. Al-Mg alloys are particularly appealing for their lightweight and exceptional mechanical properties, making them attractive for various industrial applications such as marine, automobile, aerospace, etc. In this study, an Al-5%Mg alloy single wall has been built through CMT-WAAM using Current at 110A, Travel Speed (TS) of 7 mm/sec, and Gas Flow Rate (GFR) of 15L /min. The effect of unidirectional and bidirectional deposition direction on the surface quality of the fabricated sample has been investigated. Surface roughness (Ra) tests were conducted at three different zones (upper, middle, and bottom) of the specimen wall before the machining operation using a taylor hobson surtronic tester. It is concluded from the results that the S2 wall (unidirectional) has more Ra value than the S1 wall (bidirectional) in all zones due to the presence of a humping defect which results in more waviness over the S2 wall’s surface. In the bidirectional strategy, the roughness value reduces by 8.567 % (upper zone), 9.95 % (middle zone), and 13.019 % (bottom zone) than the unidirectional strategy. Thereby establishing that the deposition direction tends to build WAAM wall with a better surface finish.

Experimental Analysis and Process Parameter Optimization of Wooden Material on Wood Router

Abstract: The area of customize design gave rise to different machines. Wood engraving or wood router machine is one of the development which can be used to perform operations like drilling, engraving, cutting etc on materials like wood, plastics, acrylics, PCB board etc. This paper discusses the effect of variable factors like spindle speed, feed rate and thickness of material on surface roughness and surface roundness of engraved surface. To calculate roundness or circularity of engraved surface coordinate measuring machine Zeiss Contura G2 is used that has least count of 0.0019 mm. For calculating roughness surface roughness tester MITITOYO SJ 210 is used that has least count of 0.0019 mm. It is found that machine shows 99.8% accuracy for diameter and 99.4% accuracy for height achieved.

Effect of various surface coating methods on surface roughness, micromorphological analysis and fluoride release from contemporary glass ionomer restorations.

To evaluate the effect of various surface coating methods on surface roughness, micromorphological analysis and fluoride release from contemporary resin-modified and conventional glass ionomer restorations. A total of 72 permanent human molars were used in this study. The teeth were randomly assigned into 2 groups according to type of restorative materials used; resin modified glass ionomer cement and conventional glass ionomer (SDI Limited. Bayswater Victoria, Australia). Each group was subdivided into 3 subgroups according to the application of coat material; Sub-group1: without application of coat; Sub-group2: manufacturer recommended coat was applied and sub-group3: customized (vaseline) coat was applied. Each group was then subdivided into two divisions according to the time of testing; immediate (after 24h) and delayed (after 6 months of storage). Three specimens from each sub-group were selected for surface roughness test (AFM) and another 3 specimens for the micromorphological analysis using scanning electron microscope (SEM). For the fluoride release test, a total of 60 cylindrical discs were used (n = 60). The discs were randomly split into 2 groups according to type of restorative materials used (n = 30); resin modified glass ionomer cement and conventional glass ionomer. Each group was subdivided into 3 subgroups (n = 10) according to the application of the coat material; Sub-group1: without application of coat; Sub-group2: with the manufacturer recommended coat and sub-group3: with application of customized (vaseline) coat. Data for each test was then collected, tabulated, were collected, tabulated, and tested for the normality with Shapiro-Wilk test. Based on the outcome of normality test, the significant effects of variables were assessed using appropriate statistical analysis testing methods. Regarding the data obtained from surface roughness test, Shapiro-Wilk test showed normal distribution pattern of all values (p > 0.05). Accordingly, Two-way ANOVA outcome showed that the 'type of restoration' or 'test time' had statistically significant effect on the AFM test (p < 0.05). Regarding Fluoride specific ion electrode test 2-way ANOVA followed by Least Significant Difference (LSD) Post-hoc test revealed significant difference among the groups (p < 0.05). It showed that SDI GIC group after 14 days of measurement had the highest mean of fluoride release (36.38 ± 3.16 PPM) and SDI RMGIC after 30 days of measurement had the second highest mean of fluoride release (43.28 ± 1.89 PPM). Finally, regarding the micromorphological analysis using SEM, a slight difference was observed between the studied groups. Based on the results of this study, various coatings enhance surface roughness in the initial 24h of restoration insertion. Different coat types seems that have no influence on fluoride release and the micromorphological features of the restoration/dentin interface.

Research of Layer Thickness and Selected Thermoplastic Materials and their Influence on the Surface Roughness in the Process of Fused Deposition Modeling Technology

This paper focuses on the influence of layer thickness and five selected thermoplastic materials on the surface roughness of cuboidal sample in the process of manufacturing by Fused Deposition Modelling technology. The component, in this case, is a cuboidal specimen with the dimensions 15 mm by 15 mm by 30 mm. FDM or LPD/FFF is additive layer-based method of additive manufacturing, usually used for rapid prototyping of the prototypes and other fabricating applications which use thermoplastics materials. A geometric model is defined that takes into account the shape of the fibers of the material after application to define the theoretical roughness profile. The authors set four different layer thicknesses of the cuboid part: 0.29 mm, 0.19mm, 0.14 mm and 0.09 mm. In this experiment, authors also used five different thermoplastic filaments: ABS, ASA, HIPS, PCABS and PLA. The authors produced a total of 20 prints and the surface of each sample was measured three times in succession using a portable surface roughness tester Mitutoyo. SJ-210. The 3D printer used in the experiment was Zortrax M200. The surface roughness .in this paper is shown in .the .form of a scatter and bar graph.