Effect of Oil Paint Addition on Impact Strength of the Scleral Part of the Acrylic Ocular Prosthesis

Background: For many dental and facial restorations, acrylic resins are the materials of choice because of their appropriate physical and mechanical properties. When making the ocular prosthesis from such materials, it is essential to add the perfect shade in order to match the colour of normal eye. This, however, might have a significant effect on the mechanical properties of acrylic resins. Objective: The purpose of this study was to assess the effect of adding the white oil paint (titanium dioxide) to clear acrylic resins on their impact strength. Methods: 20 samples were constructed from heat cured acrylic resins, and divided into two groups (control and experimental) and each group had 10 samples. The first group was made from clear acrylic resin without the addition of white oil paints, and the second group (experimental) comprised the addition of 1 ml of the white oil paints to acrylic samples. Such samples were prepared with dimensions of (80 mm X10 mm X4 mm) length, width, and thickness, respectively. All the samples were tested by the Charpy's impact strength test. They were exposed to the load till the fracture occurred. All the values were analyzed using SPSS version 20, and the independent T-test was used for comparison between the 2 groups. Results: A statistically significant decrease (P-value < 0.001) was found in the impact strength of acrylic resins after the addition of titanium dioxide oil paints (experimental group: 5.97 + 1.11, control group: 9.42+1.32 KJ/M2). Conclusion: This study concluded that the addition of titanium dioxide oil paint significantly reduces the impact of strength of the acrylic resin. It is suggested to use different stains which will have no negative effect on impact strength of the acrylic resin.

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Effect of repeated disinfections by microwave energy on the physical and mechanical properties of denture base acrylic resins

Brazilian Dental Journal ◽

10.1590/s0103-64402009000200008 ◽

2009 ◽

Vol 20 (2) ◽

pp. 132-137 ◽

Cited By ~ 9

Author(s):

Rafael Leonardo Xediek Consani ◽

Douglas Duenhas de Azevedo ◽

Marcelo Ferraz Mesquita ◽

Wilson Batista Mendes ◽

Paulo César Saquy

Keyword(s):

Mechanical Properties ◽

Impact Strength ◽

Flexural Strength ◽

Physical And Mechanical Properties ◽

Knoop Hardness ◽

Microwave Energy ◽

Bending Test ◽

Denture Base ◽

Acrylic Resins ◽

The Impact

The present study evaluated the effect of repeated simulated microwave disinfection on physical and mechanical properties of Clássico, Onda-Cryl and QC-20 denture base acrylic resins. Aluminum patterns were included in metallic or plastic flasks with dental stone following the traditional packing method. The powder/liquid mixing ratio was established according to the manufacturer's instructions. After water-bath polymerization at 74ºC for 9 h, boiling water for 20 min or microwave energy at 900 W for 10 min, the specimens were deflasked after flask cooling and finished. Each specimen was immersed in 150 mL of distilled water and underwent 5 disinfection cycles in a microwave oven set at 650 W for 3 min. Non-disinfected and disinfected specimens were subjected to the following tets: Knoop hardness test was performed with 25 g load for 10 s, impact strength test was done using the Charpy system with 40 kpcm, and 3-point bending test (flexural strength) was performed at a crosshead speed of 0.5 mm/min until fracture. Data were analyzed statistically by ANOVA and Tukey's test (α= 0.05%). Repeated simulated microwave disinfections decreased the Knoop hardness of Clássico and Onda-Cryl resins and had no effect on the impact strength of QC-20. The flexural strength was similar for all tested resins.

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The Influence of the Long-Term Storage of Hardwood on the Selected Physical and Mechanical Properties in View of Pulping

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.688.10 ◽

2016 ◽

Vol 688 ◽

pp. 10-16

Author(s):

Blažej Seman ◽

Anton Geffert ◽

Jarmila Geffertova

Keyword(s):

Mechanical Properties ◽

Impact Strength ◽

Continuous Production ◽

Beech Wood ◽

Physical And Mechanical Properties ◽

Long Term Storage ◽

The Impact ◽

Term Storage ◽

Strength In Bending

Wood is loosely stored to ensure continuous production inside paper mills where it is exposed to the effect of external factors. The impact of storage leads to some changes of mechanical and physical properties of wood, but these changes are not the same in all specimens. In this paper, it has been observed that the long term storage of wood influences the impact strength in bending and the permeability of wood for fluids. During the storage, there was a decrease of impact strength in bending of poplar heartwood by 28.3% and oak by 22.1% and mature beech wood by 37.3%. Also, there was decreased a permeability of wood, poplar sapwood 18.3 % and heartwood of 53.9%; oak sapwood by 20.0% and heartwood by 20.3%; beech sapwood 45.8% and mature wood by 48.2%. By decrease of the observed properties of the stored wood, a deterioration a quality of produced pulp can be expected (a higher Kappa number, amount reject and decrease the mechanical properties of pulp).

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ADDITION OF RICE HUSK NANOCELLULOSE TO THE IMPACT STRENGTH OF RESIN BASE HEAT CURED

Journal Of Vocational Health Studies ◽

10.20473/jvhs.v4.i3.2021.119-124 ◽

2021 ◽

Vol 4 (3) ◽

pp. 119

Author(s):

Muhammad Aditya Ramadhan Hasran ◽

Dian Noviyanti Agus Imam ◽

Bambang Sunendar

Keyword(s):

Impact Strength ◽

Mechanical Strength ◽

Rice Husk ◽

Acrylic Resin ◽

Control Group ◽

P Value ◽

Test Results ◽

Nano Cellulose ◽

Reinforcing Material ◽

The Impact

Background: One of the materials for denture bases is heat-cured acrylic resin (PMMA). This material still lacks impact strength as a mechanical strength property. The addition of reinforcing material is known to increase the mechanical strength of PMMA. One of the reinforcing materials added to PMMA is nano cellulose from rice husks, one of the wastes from agricultural products. Purpose: This study aims to determine rice husk nano cellulose's addition to the PMMA denture base's impact strength. Method: The research sample consisted of six groups, each group consisting of 8 samples selected by simple random. The PI, P2, P3, P4, P5, and K groups were PMMA with 1%, 2%, 3%, 4%, 5% nano cellulose, and without nano cellulose. Result: Mean impact strength test results were 41.50 x 10-3 ± 3.891 J / mm2 for P1, 44.13 x 10-3 ± 3,980 J / mm2 for P2, 45.63 x 10-3 ± 4,438 J / mm2 for P3, 46.87 x 10-3 ± 4,824 J / mm2 for P4, 49.12 x 10-3 ± 4.016 J / mm2 for P5 and 36.25 x 10-3 ± 1.982 J / mm2 for K. One way Anova test results with p-value of 0.000 indicates differences in the six groups (p<0.05). Conclusion: This study concludes that the impact strength value of PMMA with the addition of rice husk nano cellulose has increased compared to the control group without the addition of rice husk nano cellulose.

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Influence of Concentrations of Methacrylate and Acrylate Monomers on the Properties of Fiber Reinforced Polymethyl Methacrylate Denture Base Materials

Acta Chemica Iasi ◽

10.2478/achi-2018-0020 ◽

2018 ◽

Vol 26 (2) ◽

pp. 329-350 ◽

Cited By ~ 2

Author(s):

Faik Tugut ◽

Mehmet Turgut ◽

Dursun Saraydin

Keyword(s):

Mechanical Properties ◽

Impact Strength ◽

Testing Machine ◽

Weight Ratio ◽

Acrylic Resin ◽

Bending Test ◽

Control Group ◽

Test Machine ◽

Fiber Reinforced ◽

Significant Difference

Abstract The study aimed to evaluate the effects of adding different concentrations of 2 hydroxyethyl methacrylate (HEMA), 2-hydroxyethyl acrylate (HEA), ethyl methacrylate (EA) and isobutyl methacrylate (IBMA) monomers on the structural, thermal and mechanical properties of a fiber reinforced heat-polymerized acrylic resin. For each test, 126 acrylic resin specimens were fabricated and divided into 6 groups with 7 specimens each. One group was the control group, the other one is a fiber reinforced group and others were the test groups, which were formed according to the different concentrations of monomers. 6 mm length, and the weight ratio of 3% short glass fibers are added to acrylic powder polymerized by heating. The 2%, 5%, 10%, at 20 % ratios of different comonomers added to a monomer of MMA are composed of copolymer structures. Flexural strength was assessed with a three-point bending test using a universal testing machine. Impact strength testing was conducted using an impact test machine by the Charpy method. The analysis of the connection between acrylic resin and fiber by SEM and structural changes in the acrylic resin was investigated by FTIR spectroscopy. Data analyses using analysis of Kruskal-Wallis and Mann-Whitney U tests (α=0.05) significant difference tests showed that adding 2%, 5% HEMA and IBMA monomers significantly increased the flexural and impact strength compared to the control, only fiber and others group (P< 0.05). It is observed that the process of adding low concentration of HEMA and IBMA monomers improved certain mechanical properties of fiber reinforced with polymethylmethacrylate.

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The Difference of Impact Strength in Acrylic Resin Self-Cured with the Addition of Zirconium Dioxide (ZrO2) Nanoparticles

DENTA ◽

10.30649/denta.v12i1.167 ◽

2018 ◽

Vol 12 (1) ◽

pp. 51

Author(s):

Widaningsih Widaningsih ◽

Annete Juwita ◽

Puguh Bayu Prabowo

Keyword(s):

Impact Strength ◽

Zirconium Dioxide ◽

Acrylic Resin ◽

Zro2 Nanoparticles ◽

Control Group ◽

Control Group Design ◽

Post Test ◽

The Difference ◽

The One ◽

The Impact

Background: Self-cured acrylic resin is a material used for repairing broken and fractured dentures. Zirconium dioxide (ZrO2) is a reinforcing material that is being developed as an additive to the acrylic resin. Objective: to determine the effect of zirconium dioxide (ZrO2) addition on self-cured acrylic resin on impact strength. Material and Methods: This study was a true experimental laboratory study with the design of a post-test only control group design, using 24 pieces of self-cured acrylic resin measuring 65 x 10 x 2.5 mm divided into 4 groups with and without zirconium addition dioxide (ZrO2) nanoparticles. Zirconium dioxide (ZrO2) nanoparticles were silanized first by mixing the silane coupling agent. Furthermore, the impact strength was tested on the plate. The data obtained were analyzed using the One Way ANOVA test. Results: there were significant differences in the impact strength between the groups with a significance value of 0,000 (p <0.05). Conclusion: there was a difference in the increase of impact strength in acrylic resin self-cured with the addition of ZrO2 nanoparticles concentrations of 3%, 5%, and 7%. Key words: Self cured acrylic resin, zirconium dioxide, impact strength Correspondence : Widaningsih, Department of Prosthodonti, Faculty of Dentistry, Hang Tuah University, Arif Rahman Hakim 150, Sukolilo, Surabaya, Phone 0818312757, Email: <a href="mailto:[email protected]">[email protected]</a>

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On the Methods for Assessing the Resistance of Steels to Brittle Fracture

Occupational Safety in Industry ◽

10.24000/0409-2961-2021-5-59-64 ◽

2021 ◽

pp. 59-64

Author(s):

A.P. Korchagin ◽

◽

K.A. Kuznetsov ◽

A.M. Kuznetsov ◽

S.I. Kirillov ◽

...

Keyword(s):

Mechanical Properties ◽

Brittle Fracture ◽

Impact Strength ◽

Low Temperatures ◽

Physical And Mechanical Properties ◽

Correct Choice ◽

Temperature Dependences ◽

And Control ◽

The Impact ◽

Resistance To Brittle Fracture

The problem of assessing steels durability, their resistance to brittle fracture in the structures used in various branches of industry, remains relevant at the development of the new equipment and control of the old equipment. Standard strength calculations do not give a complete picture of the ability of steels due to their physical and mechanical properties to resist the formation and further development of defects and cracks under the action of actual stresses. The correct choice of a structural material for technical devices operating at low temperatures, knowledge of its characteristics of resistance to brittle fracture, understanding of brittle fracture mechanism at low temperatures and research in this area are of great importance. Since 1980s, JSC IrkutskNIIkhimmash systematically conducts the research works related to impact strength characteristics. These works are carried out in connection with the need for assessing the resistance to brittle fracture of metal of the equipment for storing oil products, vessels and pipelines, drill pipes and tubing, etc. As a result of many years of research, the authors accumulated significant experimental material in the form of temperature dependences of impact strength - both for the material of various types of blanks (sheets, pipes, forgings) in the state of delivery, and for the metal of technical devices elements after their operation of various duration. The main objective of the article is to assist specialists in establishing the correct choice of steel for the new or old structures in terms of their resistance to brittle fracture without conducting special studies. Specialists can select the closest steel analogue (on chemical composition, mechanical properties, and the type of product without making cuts from the structure or blanks for additional research), and set the numerical value of the impact strength, critical temperature of brittleness and the stress intensity factor for any temperature in the range from –40 to 20° С in order to use them in further calculations.

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Polytetrafluorethylene added to acrylic resins: mechanical properties

Brazilian Dental Journal ◽

10.1590/s0103-64402010000100009 ◽

2010 ◽

Vol 21 (1) ◽

pp. 55-59 ◽

Cited By ~ 12

Author(s):

Fabiana Gouveia Straioto ◽

Antonio Pedro Ricomini Filho ◽

Alfredo Júlio Fernandes Neto ◽

Altair Antoninha Del Bel Cury

Keyword(s):

Mechanical Properties ◽

Impact Strength ◽

Flexural Strength ◽

Flexural Modulus ◽

Peak Load ◽

Surface Hardness ◽

Acrylic Resin ◽

Denture Base ◽

Standard Data ◽

Acrylic Resins

The addition of different polymers, such as polytetrafluorethylene (PTFE), to denture base resins could be an option to modify acrylic resin mechanical properties. This study evaluated the surface hardness, impact and flexural strength, flexural modulus and peak load of 2 acrylic resins, one subjected to a long and another subjected to a short polymerization cycle, which were prepared with or without the addition of 2% PTFE. Four groups were formed according to the polymerization cycle and addition or not of PTFE. Forty specimens were prepared for each test (10 per group) with the following dimensions: hardness (30 mm diameter x 5 mm thick), impact strength (50 x 6 x 4 mm) and flexural strength (64 x 10 x 3.3 mm) test. The results of the flexural strength test allowed calculating flexural modulus and peak of load values. All tests were performed in accordance with the ISO 1567:1999 standard. Data were analyzed statistically by ANOVA and Tukey's test with the level of significance set at 5%. No statistically significant differences (p>0.05) were found for surface hardness. Flexural strength, impact strength and peak load were significantly higher (p<0.05) for resins without added PTFE. The flexural modulus of the acrylic resin with incorporated 2% PTFE polymerized by long cycle was significantly higher (p<0.05) than that of the other resins. Within the limits of this study, it may be concluded that the addition of PTFE did not improve the mechanical properties of the evaluated acrylic resins.

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Enhancing the impact strength of acrylic resin base plate by adding non-dental E-glass fiber

Majalah Kedokteran Gigi Indonesia ◽

10.22146/majkedgiind.42939 ◽

2021 ◽

Vol 6 (2) ◽

pp. 106

Author(s):

Mara Gustina ◽

Widjijono Widjijono ◽

Endang Wahyuningtyas

Keyword(s):

Impact Strength ◽

Glass Fiber ◽

Fiber Orientation ◽

Base Plate ◽

Acrylic Resin ◽

Impact Testing ◽

Control Group ◽

Anova Test ◽

The Impact ◽

One Way Anova

Non-dental glass fiber is one of the materials that can be used to increase the impact strength of a acrylic resin base plate, containing a similar composition to that of dental e-glass fiber. Orientation and positions of fiber affect the reinforcement effectiveness. This research aimed to examine the effect of the orientation of non-dental glass fiber in the compression position on the impact strength of an acrylic resin base plate. The research was conducted on 16 acrylic resin plates with fiber (65 mm x 10 mm x 2.5 mm) addition. The samples were divided into 4 groups (combination of different woven orientation unidirectional, bidirectional woven in the compression position, and control). The material used in this study was heat-cured acrylic resin QC-20 brand, non-dental glass fiber (without any brand). Impact strength was tested using an impact testing machine. The data obtained were analyzed using one-way ANOVA test and LSD (p<0.05). In this research the impact strength of the base plate with the addition of fiber increased 8.54 ± 2.21; 13.21 ± 2.34; 16.81 ± 2.80 kJ/m2 compared to that of the control group, i.e. 4.98 ± 1.05 kJ/m2. One-way ANOVA test showed a significant effect (p<0.05) of the fiber orientation variations on the compression position. This research concluded that the addition of nondental e-glass fiber (composed of SiO252.56-56.88%), diameter 17.12–20.03 µm) in the compression zone increases theimpact strength of acrylic resin base plate. Fibers with unidirectional orientationprovides the highest increase in the impact strength of acrylic resin base plate.

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IMPACT STRENGTH TEST ON ADDITION OF AGAVE SISALANA FIBER AND E-GLASS FIBER IN ACRYLIC RESIN DENTAL PLATE REPAIR

Interdental Jurnal Kedokteran Gigi (IJKG) ◽

10.46862/interdental.v17i1.2073 ◽

2021 ◽

Vol 17 (1) ◽

pp. 49-55

Author(s):

Ni Kadek Sugianitri ◽

◽

Suhendra Suhendra ◽

Keyword(s):

Impact Strength ◽

Glass Fiber ◽

Acrylic Resin ◽

Control Group ◽

Denture Base ◽

Denture Plate ◽

Significant Difference ◽

The Impact ◽

Agave Sisalana ◽

Fiber Addition

Introduction: Acrylic resin is the most common material for the denture base because the acrylic resin has good esthetics, ease of processing, reparability, and inexpensive. A disadvantage of acrylic resin is that it is easy to be cracked. One of the ways to resolve this problem is by adding agave sisalana fiber and E-glass fiber. The purpose of this study was to find out the effect of the addition of agave sisalana fiber and E-glass fiber on the impact strength of an acrylic resin denture plate reparation. Material and Method: The experiment involved twenty-seven plates of heat-cured acrylic with the dimensions of 55x 10 x 10 mm with the 26 x 5 x 4 mm for the cavity to measure, each measurement divided into three groups, with nine samples for each group. The first group was a control group (without fiber), the second group was a group with agave sisalana fiber addition, the third group was a group with e-glass fiber addition. All plates were soaked in distillation water for one day at 37o C. Plates were tested for impact strength using the Charpy method. All data obtained were analyzed with one-way ANOVA followed by LSD (Least Significant Difference) with p<0,05. Result and Discussion: The result showed that the influences of impact strength between without fiber with agave sisalana fiber and E-glass fiber addition on acrylic denture reparation. Acrylic denture reparation in both fibers with concentration 3,3%, agave sisalana fiber has the highest impact strength rather than e-glass fiber. Conclusion: The conclusion of this study is that there is an increase in impact strength with agave sisalana fiber and E-glass fiber addition on acrylic denture reparation and agave sisalana fiber has the highest impact strength.

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TiO2-Nanofillers Effects on Some Properties of Highly- Impact Resin Using Different Processing Techniques

The Open Dentistry Journal ◽

10.2174/1874210601812010202 ◽

2018 ◽

Vol 12 (1) ◽

pp. 202-212 ◽

Cited By ~ 4

Author(s):

Hawraa Khalid Aziz

Keyword(s):

Thermal Conductivity ◽

Impact Strength ◽

Color Stability ◽

Acrylic Resin ◽

Water Bath ◽

Control Group ◽

Significance Level ◽

Significant Difference ◽

And Control ◽

The Impact

Background: The criteria of conventional curing of polymethyl methacrylate do not match the standard properties of the denture base materials. Objectives: This research was conducted to investigate the addition of TiO2 nano practical on impact strength, thermal conductivity and color stability of acrylic resin cured by microwave in comparison to the conventional cured of heat-polymerized acrylic resin. Materials and Methods: 120 specimens made of high impact acrylic resin were divided into two main groups according to the type of curing (water bath, microwave), then each group was subdivided into two groups according to the addition of 3% TiO2 nano-fillers and control group (without the addition of TiO2 0%). Each group was subdivided according to the type of test into 3 groups with 10 specimens for each group. Data were statistically analyzed using Student t-test to detect the significant differences between tested and control groups at significance level (P<0.05). Results: According to curing type methods, the results showed that there was a significant decrease in impact strength of microwaved cured resin, but there was no significant difference in the thermal conductivity and color stability of resin. In addition, by using nanofiller, there was a significant increase in the impact strength and color stability with the addition of 3% TiO2 nanofillers, but no significant difference was found in the thermal conductivity of the acrylic resin. Conclusion: The microwave curing of acrylic resin had no change in the color stability and thermal conductivity in comparison to the water bath, but the impact strength was decreased. The addition of 3% TiO2 improved the impact and the color stability, but the thermal conductivity did not change.

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