Effectiveness of Two Type Coupling Agent of Dental Composite Nanofiller Prototype with Addition of Acetone in Preparation

2018 ◽  
Vol 782 ◽  
pp. 244-249
Author(s):  
Elin Karlina ◽  
Nina Djustiana ◽  
Renny Febrida ◽  
Yanwar Faza ◽  
Seniyah ◽  
...  

Nano size of ceramic filler (nanofiller) are tend to possess difficulties to be covered by resin matrix due to large surface area to volume ratio. Addition of aceton known as the diluent agent by introducing more content of filler as well as helping distribution of the filler in the resin matrix in application of dental composite restoration. In this study, a total 24 specimens of dental composite prototype; nanofiller-TMPS and nanofiller-MPTS were prepared using a customized acrylic mold and they were divided into two groups based on filler/resin ratio (n=6 each group). In the process of dental composite making, acetone were added into resin; 1 ml (filler/resin, 50/50) and 5 ml (filler/resin, 80/20) untill specific consistency obtained. The specimens were stored in distilled water for 24 hours at 37°C then subjected to hardness test using Vickers hardness tester machine, LECO – Japan M– 400–H1 with the load of 200 grams for 15 seconds (ADA Specification No. 27). Data were statistically analyzed using t independent test (α=0.05). The result revealed that dental composite prototype contain nanofiller-MPTS with filler/resin rasio (50/50) were statistically significant higher than dental composite prototype contain nanofiller-TMPS with same ratio (p<0.05). Otherwise, dental composite prototype with filler/resin ratio (80/20) were no observed statistically significant differences for both nanofiller-TMPS and nanofiller-MPTS (p>0.05). As conclusion, nanofiller modified MPTS are more effective to elevate surface hardness of dental composite prototype than nanofiller-TMPS for 50/50 filler/resin ratio

2014 ◽  
Vol 8 (1) ◽  
pp. 144-147 ◽  
Author(s):  
Seyed Mostafa Mousavinasab ◽  
Mehrdad Barekatain ◽  
Elahe Sadeghi ◽  
Farzaneh Nourbakhshian ◽  
Amin Davoudi

Introduction:Hardness is one of the basic properties of dental materials, specially composite resins which is relevant to their polymerization. The aim of this study was to evaluate the effect of light curing distance and the color of clear Mylar strips on surface hardness of Silorane-based (SCR) and Methacrylate-based composite resins (MCR).Materials and methods:40 samples of MCRs (Filtek Z250) and SCRs (Filtek P90) were prepared in size of 5 mm×2 mm (80 samples in total). The samples divided into 8 groups (10 samples in each one) based on the color of clear Mylar strips (white or blue) and distance from light curing source (0 mm or 2 mm). All the samples cured for 40 second and stored in incubator for 24 hours in 37°C temperature. Surface hardness test was done by Vickers test machine and the collected data were analyzed by one-way ANOVA and paired T-test by using SPSS software version 13 at significant level of 0.05.Results:MCRs cured with blue Mylar strips from 0 mm distance had the highest (114.5 kg/mm2) and SCRs cured with white Mylar strips from 2 mm distance had the lowest (42.2 kg/mm2) mean of surface hardness. Also, the results of comparison among SCRs and MCRs showed significant differences among all groups (all P values <0.01).Conclusion:The hardness decreased as the distance increased and the blue Mylar strips provided higher hardness than clear ones. Also, Filtek Z250 showed higher hardness compared to Filtek P90.


2013 ◽  
Vol 25 (3) ◽  
Author(s):  
Amalina Putri ◽  
Rahmi Alma Farah Adang ◽  
Opik Taofik Hidayat

Composite restoration is frequently found on teeth before doing any bleaching treatment. Hydrogen peroxide is a bleaching agent which enable transition to one of the composite physical properties. The aim of this research was to observe the difference of surface hardness between methacrylate and silorane based composite resin after application of 40% hydrogen peroxide. This true experiment involved 36 specimens from two different disc-shaped methacrylate and silorane based composite resins, with 18 specimens methacrylate and 18 silorane. Every specimen groups were immersed in artificial saliva solution and divided into two groups; the first group consisted of 9 specimens of control which were tested directly using microvickers hardness tester and another group consisted of 9 specimens which had been added by 40% hydrogen peroxide for hardness test. The result showed the different surface hardness average value of metachrylate and silorane based composite resin after application of 40% hydrogen peroxide. The surface hardness of methacrylate and silorane based composite resins was 41.8 VHN and 33.7 VHN (p>0.05) with t-test, respectively. From this study concluded that there was no significant difference between methacrylate and silorane based composite resins after 40% hydrogen peroxide application.


2018 ◽  
Vol 25 (5) ◽  
pp. 98-102
Author(s):  
V. V. Tairov ◽  
A. A. Arutunova ◽  
K. K. Egunyan ◽  
I. O. Kamyshnikova ◽  
V. A. Ivashchenko ◽  
...  

Aim. This study was designed to evaluate the effectiveness of preventing the formation of a layer inhibited by oxygen or reducing its amount using various means.Materials and methods. The study was performed at the Department of Therapeutic Dentistry of the FSBEI HE KubSMU of the Ministry of Health care of Russia and the laboratory instrument factory "Cascade", Krasnodar. The composite Filtek Ultimate (3M ESPE, USA) was used for the production of model samples by placing the composite material in clean plastic molds with a diameter of 13.5 mm, thickness of 4 mm and polymerization, the following materials were selected to prevent contact of oxygen with the surface of the composite: glycerin solution, lavsan plate, Teflon tape. For the comparison with the standard method of elimination of the layer inhibited by oxygen we used the finishing of the surface of the composite. The surface hardness of the samples of each group and subgroup was measured using the apparatus-hardness tester PMT-3 by the Vickers method. The multivariate analysis of variance (ANOVA) was conducted in Statistica software 13. The samples were stained separately with a solution of "Lipton" tea from 2015 for 3 years. The degree of pigment deposition was evaluated.Results. The determining factor in the long-term functioning of the composite restoration is the stability of the surface layer. The results of the study showed the lowest microhardness of the samples from the group without any blockers of oxygen penetration without finishing (56HV), the highest microhardness was in samples from the group covered with Teflon tape with finishing (107HV). The probability value p<0.05 was obtained for all study groups. The results of the color change of the restoration were evaluated in the coloring medium. The assessment of changes in the coloring was carried out for 3 years. The results of staining allowed to confirm the obtained data of the study: 1) the intensity of staining of all samples increases over time, 2) the samples from the groups without glycerin coating were stained to a greater extent before the polymerization, without finishing in comparison with the samples from the groups without glycerin but with finishing, 3) the sample with glycerin coating and finishing was stained the least.Conclusion. Thus, the results of the study allow us to recommend using the means preventing the formation of the oxygeninhibited later to improve the efficiency of the restoration of the composite and increase the duration of its functioning. Depending on the clinical situation, glycerin, lavsan plate or Teflon tape can be used as oxygen blockers.


2019 ◽  
Vol 14 (1) ◽  
pp. 110
Author(s):  
Assiss. Prof. Dr. Sabiha Mahdi Mahdi ◽  
Dr. Firas Abd K. Abd K.

Aim: The aimed study was to evaluate the influence of silver nitrate on surfacehardness and tensile strength of acrylic resins.Materials and methods: A total of 60 specimens were made from heat polymerizingresins. Two mechanical tests were utilized (surface hardness and tensile strength)and 4 experimental groups according to the concentration of silver nitrate used.The specimens without the use of silver nitrate were considered as control. Fortensile strength, all specimens were subjected to force till fracture. For surfacehardness, the specimens were tested via a durometer hardness tester. Allspecimens data were analyzed via ANOVA and Tukey tests.Results: The addition of silver nitrate to acrylic resins reduced significantly thetensile strength. Statistically, highly significant differences were found among allgroups (P≤0.001). Also, the difference between control and experimental groupswas highly significant (P≤0.001). For surface hardness, the silver nitrate improvedthe surface hardness of acrylics. Highly significant differences were statisticallyobserved between control and 900 ppm group (P≤0.001); and among all groups(P≤0.001)with exception that no significant differences between control and150ppm; and between 150ppm and 900ppm groups(P>0.05).Conclusion: The addition of silver nitrate to acrylics reduced significantly the tensilestrength and improved slightly the surface hardness.


2021 ◽  
Vol 19 (2) ◽  
pp. 77-82
Author(s):  
Fadhil K. Farhan ◽  
Aws Abbas Hussein ◽  
Ali Q. Tuama

The liquid and mechanical mixing method was used in addition to ultrasound technology to prepare samples according to standard conditions. The percentage of cementing with ceramic powder was adopted from 1% to 4% as a weight ratio, and by using mixing drivers, nanocomposites were prepared depending on the theoretical density of the components. The velvet density was measured using Archimedes' method, and the results showed a successive improvement and increase in density with the weight ratio of addition. The results of the particulate hardness test showed a significant improvement in the results of the prepared nanostructures compared to the base sample (pure epoxy). With regard to the properties of wear resistance (wear modulus) using the screw-on-disk method, the cemented samples showed a higher wear resistance compared to the base sample. The results were interpreted based on the values of density and hardness in addition to the properties possessed by the ceramic powder of high surface area and average granular size of 32 nanometers through scanning electron microscopy. In this work, nanostructures based on (a polymer) supported with nanoscale zirconium dioxide powder were developed.


2018 ◽  
Vol 2 (2) ◽  
Author(s):  
A. Noor Setyo HD ◽  
Sri Widodo

This study aims to determine the Hardness and Toughness of cast iron after undergoing a Tempering process with independent variables heating time and dependent Hardness, microstructure and toughness Impack. Quenching was carried out at temperatures of 7750C, 8000C and 8250C in cold water media, while Tempering was carried out at temperatures of 2000C, 3000C and 4000C with a holding time of 15 minutes. Vickers Hardness test results using "Micro Hardness Tester" after Quenching have increased by an average of 95.6% at Quenching 7750C, 99.8% at Quenching 8000C and 107.1% at Quenching temperature 8250C from Hardness value of row material of 256.6 BHN or 260.8 VHN0,040. The maximum hardness value is obtained 531.4 BHN or 553.6 VHN 0,040 at Quenching temperature 8250C and the lowest Hardness of 501.8 BHN or 541,8 VHN0,040 at Quenching 7750C temperature, has Cementite phase as a matrix with little Martensite, is due to treatment The partial tempering of Martensite is replaced by the ferrite phase between Cementites. The results of the study concluded that at Tempering temperatures of 2000C, 3000C and 4000C, the toughness of FC 30 experienced an increase of 106.5%, 121.9% and 130.5% from the initial energy of 5.21 Joule / mm2, whereas violence decreased by 88, 6%, 80.8% and 40.4% of the original Hardness of 260.8 VHN 0,040


2018 ◽  
Vol 30 (2) ◽  
pp. 78
Author(s):  
Muhammad Lukman Nur Hakim ◽  
Yanwar Faza ◽  
Zulia Hasratiningsih ◽  
Nina Djustiana ◽  
Bambang Sunendar

Introduction: Several factor limits of services of dental composite have triggered further improvement. ZrO2-Al2O3-SiO2 system as filler of dental composite had been developed with sol-gel technique. Ultrasonic homogeniser were reported to change the particle size ditribution or shape. Unifom size and distribution of particle is believed to help define the behavior of hardness properties. Methods: The study was an laboratory experimental design. Filler ZrO2-Al2O3-SiO2 system were developed via sol-gel methods. Post calcination process, filler were immerse in ethanol and applied with ultrasonic homogeniser, with various amplitude i.e 50 rpm, 60 rpm and 80 rpm then named sample A, B, and C. XRD, SEM anda PSA were used to characterize of filler system. Subsequent filler were used to fabricate dental composite then evaluate the hardness value using micro-hardness tester. One–way ANOVA was used to analysis the statistical result of hardness value. Results: XRD pattern of three sample were similar in which tetragonal zirconia was prominent (57-61 %) followed by monoclinic zirconia (24-25%) and amorphous (15-17 %). While, SEM and PSA characterization showed amplitude 50 rpm (sample A) produce more uniform size and well-distributed particle filler than the others. In contrary, sample B and C showed higher peak in PSA results. It means there was dominating of filler with particular size.  However, the hardness value did not show significant differences between those filler (p>0,05). Conclusion: Dental composite that contain of different uniformity and distribution of filler ZrO2-Al2O3-SiO2 system has no significantly differences of hardness value.


2019 ◽  
Vol 3 (1) ◽  
pp. 40-45
Author(s):  
Basori Basori ◽  
Ferry Budhi Susetyo

The type of electrode used in the SMAW process has many types, such as E 6010, E 6011, E 6012, E 6013, E 6020, E6027. In this case the type E 6013 is the most widely used. Certainly the type E 6013 is produced by different manufacturers as well. From penelurusan researchers of this type have different prices in accordance with companies that sell it. For that reason researchers are interested to compare the three manufacturing outputs for the type E 6013 in terms of its mechanical properties. Making a specimen welding electrode cut material to be used. then sandpaper the material that has been cut so that no remaining pieces are still attached. The next step to do the welding process with three types of E6013 elekroda. The welding is carried out until it reaches the layer layer 10 mm thickness, then the bottom plate is discarded and the weld deposit deposits only The impact strength and surface hardness value are inversely proportional. For the impact test, the E1 electrode sample specimen has the highest impact strength value and the E3 electrode sample specimen has the lowest impact strength value. While on the hardness test specimen E3 electrode sample has the highest hardness value and sample specimen E1 electrode has the lowest hardness value. This can prove that the harder the object is the more brittle the object.


2014 ◽  
Vol 966-967 ◽  
pp. 386-396 ◽  
Author(s):  
Yuan Ching Lin ◽  
Jia Bin Bai ◽  
Jiun Nan Chen

The austenitic stainless steel (SS) of AISI 304L is widely used in industrial applications because of its superior anti-corrosion resistance. However, the material suffers from a lower hardness, thus reducing wear resistance. In this study, AISI 304L was clad with tungsten boride (WB) ceramic powder using the gas tungsten arc welding (GTAW) process to increase surface hardness and improve wear resistance. The microstructure of the cladding layer was investigated using an X-ray diffractometer (XRD), an electron probe microanalyzer (EPMA), and a scanning electron microscope (SEM) with an energy dispersive spectrometer (EDS). The hardness distribution of the cladding layer was measured using a micro-Vickers hardness tester. Wear tests were conducted with a pin-on-disc tribometer at the ambient condition, while simultaneously monitoring friction coefficient variation. Surface frictional temperature was recorded with K-type thermocouples during wear tests. The worn morphology of the tested specimens was observed by SEM to identify wear characteristics. The results show that WB cladding successfully increased the hardness and the wear resistance of AISI 304L. Keywords: GTAW, WB, wear resistance, microstructure


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