scholarly journals Comparison of the Effects of Sugar-free Solutions, Cola, Mouthwash on the Surface Hardness and Roughness of Temporary Crown Materials

2022 ◽  
Vol 58 (4) ◽  
pp. 197-209
Author(s):  
Nuran Yanikoglu ◽  
Zeynep Yesil Duymus ◽  
Sebahat Findik Aydiner
Keyword(s):  
Surface Roughness ◽  
Oral Cavity ◽  
Analysis Of Variance ◽  
Traditional Method ◽  
Surface Hardness ◽  
Micro Hardness ◽  
Restorative Materials ◽  
Cad Cam ◽  
Hardness Values

The aim of this study is to investigate the effect of polishing with different solutions on the surface roughness and hardness of two different polymethylmethacrylate temporary restoration materials. In the study, two different temporary crown materials prepared in the CAD / CAM system and prepared by the traditional method were used to test a total of 224 pieces of 10 mm diameter and 2 mm thickness. After the surface roughness and micro hardness values were measured, samples were randomly divided into seven groups among themselves; After waiting 24 h, 1 and 3 weeks, values were measured again. Data were evaluated using 3-way analysis of variance (ANOVA) and Tukey HSD test. The temporary restorative materials surface hardness and roughnesses are important to be able to stay in oral cavity without any changes. And it is also important to determine which of the materials (prepared by temporary conventional materiels or by the CAD/CAM) are less effected by the liquids in oral cavity.

scholarly journals Effect of Friction Stir Processing on Microstructural, Mechanical, and Corrosion Properties of Al-Si12 Additive Manufactured Components

Metals ◽  
2020 ◽  
Vol 10 (1) ◽  
pp. 85 ◽  
Author(s):  
Ghazal Moeini ◽  
Seyed Vahid Sajadifar ◽  
Tom Engler ◽  
Ben Heider ◽  
Thomas Niendorf ◽  
...  
Keyword(s):  
Surface Roughness ◽  
Surface Quality ◽  
Corrosion Behavior ◽  
Friction Stir Processing ◽  
Micro Hardness ◽  
Corrosion Properties ◽  
Microstructural Investigation ◽  
Friction Stir ◽  
Size Refinement ◽  
Hardness Values

Additive manufacturing (AM) is an advanced manufacturing process that provides the opportunity to build geometrically complex and highly individualized lightweight structures. Despite its many advantages, additively manufactured components suffer from poor surface quality. To locally improve the surface quality and homogenize the microstructure, friction stir processing (FSP) technique was applied on Al-Si12 components produced by selective laser melting (SLM) using two different working media. The effect of FSP on the microstructural evolution, mechanical properties, and corrosion resistance of SLM samples was investigated. Microstructural investigation showed a considerable grain refinement in the friction stirred area, which is due to the severe plastic deformation and dynamic recrystallization of the material in the stir zone. Micro-hardness measurements revealed that the micro-hardness values of samples treated using FSP are much lower compared to SLM components in the as-built condition. This reduction of hardness values in samples treated with FSP can be explained by the dissolution of the very fine Si-phase network, being characteristic for SLM samples, during FSP. Surface topography also demonstrated that the FSP results in the reduction of surface roughness and increases the homogeneity of the SLM microstructure. Decreased surface roughness and grain size refinement in combination with the dissolved Si-phase network of the FSP treated material result in considerable changes in corrosion behavior. This work addresses the corrosion properties of surface treated additive manufactured Al-Si12 by establishing adequate microstructure-property relationships. The corrosion behavior of SLM-manufactured Al-Si12 alloys is shown to be improved by FSP-modification of the surfaces.

scholarly journals Three-Point Bending Tests of Zirconia Core/Veneer Ceramics for Dental Restorations

2013 ◽  
Vol 2013 ◽  
pp. 1-5 ◽  
Author(s):  
Massimo Marrelli ◽  
Carmine Maletta ◽  
Francesco Inchingolo ◽  
Marco Alfano ◽  
Marco Tatullo
Keyword(s):  
Surface Roughness ◽  
Comparative Study ◽  
Mechanical Strength ◽  
Surface Hardness ◽  
Mechanical Tests ◽  
Bending Tests ◽  
Three Point Bending ◽  
Dental Restorations ◽  
Modes Of Failure ◽  
Cad Cam

Introduction. The mechanical strength and the surface hardness of commercially available yttrium-doped zirconia were investigated. Furthermore, a comparative study of eight different ceramic veneers, to be used for the production of two-layered all-ceramic restorative systems, was carried out.Materials and Methods. Four types of zirconia specimens were analyzed, according to a standard ISO procedure (ISO 6872). Besides, two-layered zirconia-veneer specimens were prepared for three-point bending tests.Results. A strong effect of the surface roughness on the mechanical strength of zirconia specimens was observed. Finally, a comparative study of eight commercially available veneering ceramics shows different modes of failure between the selected veneers.Conclusion. The results indicate that close attention should be paid to the preparation of zirconia-based crowns and bridges by CAD/CAM process, because surface roughness has an important effect on the mechanical strength of the material. Finally, the results of the mechanical tests on two-layered specimens represent an important support to the choice of the veneering ceramic.

scholarly journals Effect of two different commonly available energy drinks on surface micro hardness of tooth color restorative materials

2014 ◽  
Vol 2 (3) ◽  
pp. 269
Author(s):  
Nazish Fatima ◽  
Mehwish Hussain
Keyword(s):  
Energy Drinks ◽  
Time Interval ◽  
Base Line ◽  
Micro Hardness ◽  
Tooth Color ◽  
Hardness Tester ◽  
Significant Difference ◽  
Restorative Materials ◽  
Insignificant Difference ◽  
Hardness Values

AIM: The objective of present study was to assess the effect of commonly used energy drinks on surface micro hardness of tooth color restorative materials. MATERIAL AND METHODS: Sixty discs of all material were prepared in polytetrafluoroethylene mold which was 10 mm in diameter and 2 mm in thickness. Two groups were made for each material containing 10 discs; G1/G2 (vitofil), G3/G4 (vitremere), G5/G6 (Filtek Z350). After 24 hours, the discs were polished. Group 1, group 3 and group 5 were immersed in red bull for 2 minutes during whole expereiment. Group 2, group 4 and group 6 were immersed in jolt cola for 2 minutes during whole expereiment. Microhardness test were performed in digital micro hardness tester before and after immersion at different time interval. The results were statistically analyzed with the help of two-way ANOVA with repeated measurement and Tukey’s test. RESULTS: According to time interval for vitofil and vitremere there is insignificant difference between baseline and day 1 surface micro hardness values (p>0.001). Significant difference is seen between baseline micro hardness and day 7 day 14,day 30 (p<0.001). Inverse is true for Filtek Z350 there is significant difference between base line and day 1 micro hardness values(p<0.001). The difference between base line, day 7, day 14 and day 30 is insignificant (p>0.001). According to immersion media there is insignificant difference between both of them (p>0.001). CONCLUSION: The effect of energy drinks on the surface micro hardness of a restorative material depends on the duration of contact time and the material composition not on the type of drink.

scholarly journals The effects of food simulating liquids on surface roughness, hardness, and solubility of bulk fill composites

2019 ◽  
Author(s):  
Özge Gizem Cabadağ ◽  
NİHAN GÖNÜLOL
Keyword(s):  
Surface Roughness ◽  
Citric Acid ◽  
Vickers Microhardness ◽  
Surface Hardness ◽  
High Viscosity ◽  
Constant Mass ◽  
Measuring Device ◽  
Hardness Values ◽  
Roughness Measurements ◽  
Scanning Electron

Abstract BackgroundThe aim of this study was to compare the effects of food simulating liquids (FSLs) on the surface roughness, surface hardness and solubility of bulk fill composites. MethodsTwo-hundred samples were prepared from four high viscosity bulk fill composites (SonicFillTM, Tetric® EvoCeram Bulk Fill, Beautifil-Bulk Restorative, FiltekTM Bulk Fill Posterior Restorative) and a microhybrid composite (FiltekTM Z250). After the initial weights of the samples were recorded (m1), surface roughness measurements were evaluated with a profilometer. The samples were stored in 4 different FSLs for 7 days, then the second surface roughness values were recorded. Then the samples were stored in a desiccator to reach the constant mass and the values were recorded as m2. The solubility levels were calculated according to the ISO 4049: 2009 specification. The surface hardness values of the samples were determined by using the Vickers microhardness measuring device. Twenty specimens from each group were evaluated in terms of surface morphology with scanning electron microscope (SEM).ResultsBeautifil Bulk Restorative was the most affected group in terms of surface roughness after storage in FSLs and citric acid caused the highest values in this group (p<0,005). Beautifil Bulk Restorative and Filtek Z250 groups showed the highest surface hardness values, while the Tetric EvoCeram group had the lowest. The highest solubility values were detected in Beautifil Bulk Restorative group, and citric acid and ethanol caused the highest solubility values on all the tested composites. ConclusionsBeautifil Bulk Restorative group showed significant differences from the other groups in all tested parameters.

scholarly journals Vickers Micro-Hardness of New Restorative CAD/CAM Dental Materials: Evaluation and Comparison after Exposure to Acidic Drink

Materials ◽  
2019 ◽  
Vol 12 (8) ◽  
pp. 1246 ◽  
Author(s):  
Marco Colombo ◽  
Claudio Poggio ◽  
Alessandro Lasagna ◽  
Marco Chiesa ◽  
Andrea Scribante
Keyword(s):  
Glass Ceramic ◽  
Lithium Silicate ◽  
Micro Hardness ◽  
Percentage Loss ◽  
Computer Aided ◽  
Cad Cam ◽  
Nanohybrid Composite ◽  
Hybrid Ceramic ◽  
Hardness Values ◽  
Lithium Silicate Glass

CAD/CAM (computer-aided design/computer-aided manufacturing) for indirect restorative materials has been recently introduced in dentistry. The purpose of this study was to evaluate the change of the surface micro-hardness of different restorative CAD/CAM materials after exposure to a carbonated acidic drink (Coca-Cola, Coca-Cola Company, Milan, Italy). One hundred and eighty specimens of identical size (2 mm thickness) were obtained by sectioning each tested CAD/CAM block of four materials: a hybrid ceramic (CERASMART™, GC Corporation, Tokyo, Japan), a resin nano ceramic (Lava™ Ultimate, 3M, Monrovia, CA, USA), a nanohybrid composite (Grandio blocs, VOCO GmbH, Cuxhaven, Germany), and a zirconia-reinforced lithium silicate glass ceramic (VITA SUPRINITY® PC; VITA Zahnfabrik, Bad Sackingen, Germany). Forty-five specimens of each material were tested. Micro-hardness was measured at baseline, after 7 days and after 28 days. The data were analyzed. The micro-hardness of each material varied significantly after immersion in Coca-Cola. The nanohybrid composite had a high initial micro-hardness and the greatest percentage loss after acid exposure. The hybrid ceramic and the resin nano ceramic had similar percentage losses of micro-hardness values even if the second material had higher initial values. The zirconia-reinforced lithium silicate glass ceramic had the highest baseline values and the lowest percentage loss of micro-hardness. The different CAD/CAM materials presented different micro-hardness values before and after acid exposure.

scholarly journals How a 16% Carbamide Peroxide Home Bleaching Agent Affects the Surface Properties of Chairside CAD/CAM Materials?

2021 ◽  
pp. 342-353
Author(s):  
Tugba Serin-Kalay ◽  
Beyza Zaim
Keyword(s):  
Surface Roughness ◽  
Surface Analysis ◽  
Lithium Silicate ◽  
Bleaching Agent ◽  
Carbamide Peroxide ◽  
Peroxide Bleaching ◽  
Significant Difference ◽  
Computer Aided ◽  
Restorative Materials ◽  
Cad Cam

Surface changes of restorative materials after bleaching have clinical importance in terms of the durability and survival of restorations. This study aimed to evaluate the effect of home bleaching on the surface roughness, microhardness, and surface analysis of four different types of chairside computer-aided design and computer-aided manufacturing (CAD/CAM) materials. Specimens were prepared from composite resin (Brilliant Crios: BC), resin nanoceramic (Lava Ultimate: LU), polymer-infiltrated ceramic-network (Vita Enamic: VE), and zirconia-reinforced lithium silicate glass-ceramic (Vita Suprinity: VS) CAD/CAM materials. Specimens were polished using 800, 1000, 1200, and 2000 grit SiC papers. Each restorative material was randomly divided into two groups; control and bleaching (n=10). The 16% carbamide peroxide bleaching agent (Whiteness Perfect 16%, FGM) was applied to the specimens for 4 h/day for 14 days. Surface roughness values (Ra) were obtained using a profilometer, and microhardness values (VHN) were obtained using a Vickers microhardness test. Surface analysis of specimens was evaluated by scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDX). Data were analyzed Two-way ANOVA and Fisher’s Least Significant Difference (LSD) test (p<0.05). After bleaching, the surface roughness of BC (p<0.001) and VE (p<0.032) significantly increased. Bleaching did not significantly affect the microhardness of CAD/CAM materials. SEM evaluation showed material-dependent surface damages after bleaching procedures. The effect of 16% carbamide peroxide home bleaching agent on surface roughness and microhardness of chairside CAD/CAM materials is material-dependent. Before bleaching, restorative materials should be protected by applying a protective barrier and contact with the bleaching agent should be minimized. Also, after bleaching, the restoration surface should be carefully inspected, and re-polishing might be beneficial.

Influence of thermal and pH cycles on surface characteristics lithium disilicate glass-ceramic dental crowns milled with CAD/CAM process

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Yajvinder Singh ◽  
Vishal Gulati
Keyword(s):  
Surface Roughness ◽  
Glass Ceramic ◽  
Research Work ◽  
Surface Hardness ◽  
Surface Characteristics ◽  
Lithium Disilicate ◽  
Content Type ◽  
Cad Cam ◽  
Group 3 ◽  
Group 2

Purpose The paper aims to evaluate the influence of thermo-chemical cycles of oral fluids on the surface attributes (roughness and microhardness) of lithium disilicate glass-ceramic (LDC) crown restorations manufactured with CAD/CAM technology. Design/methodology/approach There have been 24 LDC crowns manufactured using the CAD/CAM process for their respective preparation dies ply methyl methacrylate (PMMA) of mandibular left second premolar tooth (n = 8 each group). The standard procedure was used to glaze 16 crown samples (Groups 2 and 3).Samples of Group 3 were aged with thermal (563°C and 5563°C) and pH (2–14) cycles. All 24 samples were tested with a Profilometer and a Vicker hardness tester was used for their surface roughness and hardness measurement, respectively. Findings In statistical examination on SPSS Statistics 20 (IBM) software, of surface roughness values (Ra) and Vicker hardness values from different groups, Tukey HSD test was executed in one-way ANOVA (a = 0.05). The means Ra for groups were accordingly Group 3 > Group1 > Group 2 (p < 0.001). Similarly, micro-hardness was in order of Group 2 > Group 1 > Group 3 (p < 0.001). Research limitations/implications The research work does not have any limitations. Originality/value Surrounding temperature and pH significantly impact the surface characteristics of lithium disilicate crown restoration. The study also reveals the inverse relationship between surface roughness and surface hardness parameters. The observed results and facts revealed well in agreement with the past research studies.

Investigation on Surface Integrity of STAVAX ESR AISI 420 Martensitic Stainless Steel by Cryogenically Treated Steel Balls with Low Plastic Burnishing Tool

2012 ◽  
Vol 504-506 ◽  
pp. 1347-1352
Author(s):  
Sivapraksam Thamizhmanii ◽  
K. Rajendran ◽  
Mohideen Rasool ◽  
Sulaiman Hassan
Keyword(s):  
Surface Roughness ◽  
Stainless Steel ◽  
Surface Integrity ◽  
Feed Rate ◽  
Martensitic Stainless Steel ◽  
Surface Hardness ◽  
Operating Parameters ◽  
Micro Hardness ◽  
Aisi 420 ◽  
Steel Balls

Low plasticity burnishing (LPB) is a new method of surface improvement, which raises the burnishing to the next level of sophistication. LPB can provide deep compression for improved surface characteristics. The study focuses on the surface roughness, micro-hardness and surface integrity aspects on soft AISI 420 STAVAX ESR martensitic stainless steel AISI 420 material. This material is pronounced as difficult to cut materials like titanium, Inconel 718 etc. The investigation of surface integrity was done on this materials in terms of operating parameters like sliding speed, feed rate and depth of penetration (DOP) identifying the predominant factors among the selected parameters. The steel balls used were cryogenically treated at sub zero temperature of -176 degrees. Sub-surface micro-hardness study were also done to asses the depth of compression altered zone, surface roughness and surface hardness. The process can be applied to critical components effectively as the LPB process has cycle time advantages and also low investment cost. This can be also realized by introducing on high speed machines. This process was studied by using cryogenically treated different ball diameters at various operating parameters. This also improved on concentricity of work material. More the depth of compression produced low surface roughness at low sliding speed, feed rate with larger ball diameter. The DOP also helps to improve on surface and sub-surface hardness and close roundness. There are limitations on DOP beyond which the surface deteriorated.

scholarly journals Surface Analysis and Spectrophotometric Evaluation of Different Esthetic Restorative Materials Frequently Exposed to a Desensitizing Agent

2021 ◽  
Vol 2021 ◽  
pp. 1-9
Author(s):  
Neven S. Aref ◽  
Reham M. Abdallah
Keyword(s):  
Surface Roughness ◽  
Color Change ◽  
Resin Composite ◽  
Surface Hardness ◽  
Test Surface ◽  
Surface Microhardness ◽  
Restorative Materials ◽  
Desensitizing Agents ◽  
Nanohybrid Composite ◽  
Frequent Exposure

Background. Patients with tooth sensitivity are frequently exposed to desensitizing agents on a regular basis. These agents might have an impact on the surface properties and color of existing oral restorations. Accordingly, this study aimed to investigate the color stability, surface microhardness, and surface roughness of resin-modified glass ionomer (RMGIC), amalgomer CR, nanohybrid, and bulk-fill resin composites restorative materials after frequent exposure to a desensitizing agent. Materials and Methods. One hundred and twenty specimens were prepared; 10 specimens for each restorative material were equally subdivided into control and desensitizing-agent-exposed groups in each test. Surface microhardness and surface roughness were evaluated using the Vickers microhardness tester and surface profilometer, respectively. The color change was measured by using a spectrophotometer using the CIE L ∗ a ∗ b ∗ formula. Surface topography was analyzed using a scanning electron microscope (SEM). The collected data were analyzed with Student’s t-test, one-way ANOVA, and Tukey post hoc tests for pairwise comparison at a level of significance of 0.05. Result. The frequent use of a desensitizing agent significantly decreased surface hardness of RMGIC, amalgomer, and bulk-fill composite materials. However, nanohybrid composite exhibited a significant surface hardness increase. The surface roughness of RMGIC, amalgomer, and nanohybrid composite increased significantly. Meanwhile, the bulk-fill resin composite showed a nonsignificant decrease. Both RMGIC and amalgomer exhibited significantly higher values of color change in comparison to those of nanohybrid and bulk-fill composites. Conclusion. The bulk-fill composite seems to be more resistant to discoloration and surface topographical changes than other tested materials on frequent exposure to the desensitizing agent. However, this exposure may pose a negative impact on its surface hardness. Bulk-fill resin composite may be the most suitable esthetic restorative in patients who frequently use desensitizing agents.

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