PENGARUH LARUTAN SODIUM HIPOKLORIT TERHADAP KEKUATAN TRANSVERSAL PADA BAHAN BASIS GIGI TIRUAN RESIN AKRILIK POLIMERISASI PANAS

Among various ways to clean the denture based material is by its immersion in disinfectant solution, such as sodium hypochlorite. Heat polymerized acrylic is denture based material that is easily broken because of its low transverse strength. This study was aimed to observe the transverse strength of denture based material heat polymerized acrylic resin after immersion in sodium hypochlorite. This research used 24 samples of heat cured acrylic resin plates measuring 65 mm long, 10 mm wide and 2.5 mm thick. The samples being divided into 4 groups were immersed in sodium hypochlorite 1% and water for 8 hours and 24 hours in 7 days. The transverse strength of acrylic plate were then tested using universal testing machine. The measurement results were statistically analyzed employing “one way ANOVA”. The result showed no significant changes on transverse strength of heat-cured acrylic plate. It was concluded that sodium hypochlorite solution did not provide any significant changes in the transverse strength of heat cured acrylic resin.

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THE EFFECT OF MIXING SODIUM HYPOCHLORITE ON COMPRESSIVE STRENGTH OF TYPE III GYPSUM PRODUCT

Andalas Dental Journal ◽

10.25077/adj.v4i2.63 ◽

2016 ◽

Vol 4 (2) ◽

pp. 132-140

Author(s):

Rezy Kurnia ◽

Hidayati Hidayati

Keyword(s):

Compressive Strength ◽

Sodium Hypochlorite ◽

Testing Machine ◽

Control Group ◽

Distilled Water ◽

Infectious Agents ◽

Type Iii ◽

Disinfectant Solution ◽

One Way Anova

Disinfection is needed to avoid transmission of infectious agents. One of disinfectant solution used is sodium hypochlorite. Disinfection should be done without changing the quality of gypsum models, so the technique of mixing a disinfectant solution on gypsum powder can be used as an alternative. The purpose of this study was to determined the effect of mixing sodium hypochlorite to the compressive strength of type III gypsum product. The study was conducted at the Laboratory of Materials and Structures, Faculty of Engineering, Andalas University using laboratory experimental method with 30 pieces of type III gypsum models as samples. Samples were divided into 5 groups, that were mixed using 0.5% sodium hypochlorite, 1% sodium hypochlorite, 2% sodium hypochlorite, 5% sodium hypochlorite and distilled water as a control group. Measurement of the compressive strength was performed with a Universal Testing Machine (UTM). The results showed that the models were mixed with 0.5% sodium hypochlorite, 1% sodium hypochlorite, 2% sodium hypochlorite and 5% sodium hypochlorite reduced the average of the compressive strength compared to the models that are mixed with distilled water. One Way ANOVA test showed that was significantly differences (p<0.05) among groups of 0.5% sodium hypochlorite, 1% sodium hypochlorite, 2% sodium hypochlorite, 5% sodium hypochlorite and distilled water as a control group. It was concluded that there were effect of mixing sodium hypochlorite to reduced the compressive strength of type III gypsum product. Keywords: type III gypsum, compressive strength, sodium hypochlorite

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Pengaruh Jenis dan Volumetrik Fiber terhadap Kekuatan Transversal Reparasi Plat Resin Akrilik

Majalah Kedokteran Gigi Indonesia ◽

10.22146/majkedgiind.9021 ◽

2015 ◽

Vol 1 (1) ◽

pp. 102

Author(s):

Pramudya Aditama ◽

Siti Sunarintyas ◽

Widjijono Widjijono

Keyword(s):

Glass Fiber ◽

Glass Fibers ◽

Testing Machine ◽

Acrylic Resin ◽

Universal Testing Machine ◽

Transverse Strength ◽

Universal Testing ◽

Group I ◽

Significant Difference ◽

Post Hoc

Resin akrilik merupakan bahan yang sering digunakan dalam pembuatan basis gigi tiruan. Kelemahan resin akrilik adalah mudah patah. Salah satu cara untuk mengatasi masalah tersebut adalah dengan menambahkan polyethylene (PE) atau glass fiber. Tujuan dari penelitian ini untuk mengetahui pengaruh jenis dan volumetrik fiber terhadap kekuatan transversal reparasi plat resin akrilik. Penelitian ini menggunakan dua puluh lima plat resin akrilik kuring panas berukuran 65 x 10 x 2,5 mm. Subjek dipreparasi untuk membuat jarak 3 mm dan sudut bevel 45o. Subjek dibagi menjadi 5 kelompok, masingmasing kelompok terdiri dari 5 subjek. Kelompok 1 (kontrol) tanpa penambahan fiber, kelompok II dengan penambahan 3,7% v/v PE fiber, kelompok III dengan penambahan 7,4% v/v PE fiber, kelompok IV dengan penambahan 3,7% v/v E-glass fiber, dan kelompok V dengan penambahan 7,4% v/v E-glass fiber. Seluruh plat direndam dalam air destilasi selama satu hari pada suhu 37oC. Pengujian kekuatan transversal plat resin akrilik dengan menggunakan Universal Testing Machine dan data yang didapat dianalisis menggunakan ANAVA dua jalur dengan tingkat kepercayaan 95%. Rerata kekuatan transversal (MPa) reparasi plat resin akrilik yang diperkuat fiber: 3,7% v/v PE fiber (67,77±3,34); 7,4% v/v PE fiber (80,37±8,42); 3,7% v/v E-glass fiber (96,72±5,43); 7,4% v/v E-glass fiber (109,44±4,98); sedangkan reparasi plat resin yang tidak diperkuat fiber menghasilkan kekuatan transversal 56,27±4,7 MPa. Hasil analisis menggunakanANAVA dua jalur menunjukkan variabel jenis dan volumetrik fiber memberikan pengaruh signifikan (p<0,05), sedangkan interaksi antara jenis dan volumetrik fiber tidak berpengaruh signifikan (p>0,05). Uji post hoc Tukey menunjukkan perbedaan signifikan (p<0,05) untuk seluruh kelompok perlakuan. Penambahan E-glass fiber dalam reparasi plat resinakrilik mampu meningkatkan kekuatan transversal lebih tinggi dibandingkan dengan menggunakan PE fiber. Peningkatan volumetrik fiber dapat meningkatkan kekuatan transversal reparasi plat resin akrilik. Effect Of Type And Volumetric Fiber On Transverse Strength Of Acrylic Resin Plate Repair. Acrylic resin is the most common denture base material. A disadvantage of acrylic resin is that it is easily fractured. One way to resolve this problem is by adding polyethylene (PE) or glass fibers. The purpose of this research is to find out about the effect of type and volumetric fiber on transverse strength of acrylic resin plate repaired. The experiment involved twenty five plates of heat cured acrylic with the dimensions of 65 x 10 x 2.5 mm. The speciments were prepared to create a 3 mm gap and 45° bevel. The subjects were divided into 5 groups; each group consisted of 5. Group I (control) was without fiber reinforcement, group II reinforced with 3.7% v/v PE fiber, group III reinforced with 7.4% v/v PE fiber, group IV reinforced with 3.7% v/v E-glass fiber, and group V reinforced with 7.4% v/v E-glass fiber. All plates were soaked in distilled water for one day at 37° C temperature. The plates were tested for transverse strength with Universal Testing Machine and all data obtained were analyzed with two way ANOVA at 95% confidence level. The mean of transverse strength (MPa) of the acrylic resin plate repair reinforced with fiber: 3.7% v/v PE fiber was (67.77±3.34); 7.4% v/v PE fiber (80.37±8.42); 3.7% v/v E-glass fiber (96.72±5.43); 7.4% v/v E-glass fiber (109.44±4.98); while the transverse strength of the acrylic resin plate with no fiber reinforced was 56.27±4.7 MPa. Two way ANOVA analysis shows that type and volumetric fiber had significant effect (p<0.05), while the interaction between type and volumetric fiber had no significant effect (p>0.05). Tukey post hoc test shows significant difference (p<0.05) for all groups. The addition of E-glass fibers in the acrylic resin plate repaired increased the transverse strength higher than that with PE fibers. The increase in volumetric fibers might improve the transverse strength of the acrylic resin plate repaired.

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Pengaruh penambahan hidroksiapatit terhadap porositas dan compressive strength basis resin akrilik heat-curedEffect of hydroxyapatite addition towards porosity level and compressive strength of heat-cured acrylic resin base

Jurnal Kedokteran Gigi Universitas Padjadjaran ◽

10.24198/jkg.v32i2.26627 ◽

2020 ◽

Vol 32 (2) ◽

pp. 91

Author(s):

Chaterina Diyah Nanik Kusumawardani ◽

Ronaldo Triputro Chondro ◽

Ivan Andrian ◽

Rima Parwati Sari

Keyword(s):

Compressive Strength ◽

Testing Machine ◽

Acrylic Resin ◽

Load Cell ◽

Control Group ◽

Porosity Level ◽

Universal Testing ◽

White Spots ◽

Sem Imaging ◽

One Way Anova

Pendahuluan: Resin akrilik heat cured (HC) merupakan pilihan utama bahan sebagai basis gigi tiruan. Hidroksiapatit (HAP) adalah molekul kristalin yang sudah banyak digunakan di kedokteran gigi. Penelitian terdahulu membuktikan bahwa HAP mampu mengurangi monomer sisa pada resin akrilik HC, yang akan mengurangi juga porositas resin akrilik tersebut. Berkurangnya porositas resin akrilik, diharapkan akan meningkatkan kekuatan mekanik resin akrilik tersebut. Tujuan penelitian menganalisis pengaruh penambahan hidroksiapatit terhadap porositas dan compressive strength resin akrilik HC. Metode: Jenis penelitian eksperimental laboratoris. Sampel penelitian 20 resin akrilik HC berbentuk silindris (6x3mm), dibagi menjadi 4 kelompok. Kelompok kontrol (tanpa penambahan HAP), kelompok HAP 2%, kelompok HAP 5%, dan kelompok HAP 10%. Permukaan sampel diteliti menggunakan SEM untuk porositasnya. Penghitungan compressive strength sampel menggunakan Universal Testing Machine (load cell 300kg/mm2). Hasil: Uji one-way ANOVA dan Tukey-HSD menunjukkan perbedaan signifikan (p<0,05) antara kelompok kontrol (90±13,5MPa) dengan 5%HAP (105±4,3MPa) dan 10%HAP (113±10,2MPa), begitu pula antara 2%HAP (96±8,4MPa) dengan 10%HAP. Uji SEM menunjukkan tidak adanya reaksi kimia antara HAP dan resin akrilik HC. Tampak pula bercak putih tersebar tidak merata pada permukaan sampel akrilik di kelompok-kelompok perlakuan. Bercak putih ditemukan meningkat sebanding dengan peningkatan konsentrasi HAP, dengan diameter yang semakin besar. Simpulan: Penambahan HAP pada basis resin akrilik HC mampu menurunkan tingkat porositas dan meningkatkan nilai compressive strength. Penurunan tingkat porositas meningkat seiring dengan penambahan HAP. Compressive strength yang paling tinggi didapatkan pada basis resin akrilik heat cured dengan penambahan 10% hidroksiapatit.Kata kunci: Compressive strength, uji SEM, resin akrilik heat cured, hidroksiapatit. ABSTRACT Introduction: Heat-cured acrylic resin has been commonly used as a denture base, whereas hydroxyapatite (HAP) is a crystalline molecule widely used in the field of dentistry. Previous research has been proofed that HAP could reduce the residual monomer of heat-cured acrylic resin, which will reduce the porosity level in advance, so it was expected for better mechanical properties. This research was aimed to analyse the effect of HAP addition towards the porosity level and compressive strength of heat-cured acrylic resin. Methods: An experimental laboratory research was conducted towards 20 cylindrical samples (6 x 3 mm) of heat-cured acrylic resins, which were divided into four groups: Control group (without HAP addition), 2% HAP addition group, 5% HAP addition group, and 10% HAP addition group. Compressive strength was tested using Universal Testing Machine (load cell of 300kg / mm2). Each sample surface porosity was observed using the scanning electron microscope (SEM). Results: One-way ANOVA and Tukey-HSD tests results showed significant differences (p < 0.05) between compressive strength in the control group (90 ± 13.5 MPa) compared to 5% (105 ± 4.3 MPa) and 10% HAP addition group (113 ± 10.2 MPa), significant differences were also shown between the 2% (96±8.4MPa) and 10% HAP addition group. SEM imaging showed that there was no chemical reaction between HAP and heat-cured acrylic resin. It showed uneven white spots in acrylic sample’s surface in all treatment groups. Those white spots were likely to be found more in the higher concentration of HAP, so did the diameter of white spots was also found more in the higher concentration. Conclusion: The addition of hydroxyapatite to the base of heat-cured acrylic resin can reduce the level of porosity and increase the compressive strength value. The decrease in the porosity level increases with the addition of hydroxyapatite. The highest compressive strength is obtained with the addition of 10% hydroxyapatite.Keywords: Compressive strength, SEM imaging, heat-cured acrylic resin, hydroxyapatite.

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Pengaruh Desinfeksi Energi Microwave Terhadap Kekuatan Transversal Resin Akrilik Polimerisasi Panas

Jurnal Material Kedokteran Gigi ◽

10.32793/jmkg.v8i1.363 ◽

2019 ◽

Vol 8 (1) ◽

pp. 17

Author(s):

Sefty Aryani Harahap ◽

Lasminda Syafiar ◽

Yosepha Yulinda Esdaria Lubis

Keyword(s):

Testing Machine ◽

Acrylic Resin ◽

Electronic System ◽

Microwave Energy ◽

Denture Base ◽

Mean Values ◽

Base Materials ◽

Test Speed ◽

Universal Testing ◽

One Way Anova

Disinfectant by microwave energy is highly recommended as a solution to solve the problem of chemical disinfection on denture bases. One of the denture base materials is heat cured acrylic resin. Aim, to evaluate the effect of disinfectant by microwave energy with different time on the transversal strength of heat cured acrylic resin. 30 plates (n = 6) of heat cured acrylic resin with size 65x10x2,5 mm were divided into 5 groups (control; and microwave energy disinfected for 2, 4 , 6, and 8 minutes with 650 Watts of power). Transversal strength test was carried out using Torsee's Electronic System Universal Testing Machine with a test speed of 0.1 mm / second, and a load cell of 50 kgf. Data analyzed using one-way ANOVA and LSD pos hoc. Results, there were significant differences in the transverse strength among all groups (p <0.05). Mean values of all groups were 103.59 ± 0.66 MPa; 112.02 ± 2.10 MPa; 117.48 ± 1.73 MPa; 125.46 ± 2.25 MPa; and 135.89 ± 1.56 MPa respectively. Conclusion, the longer it is disinfected by microwave energy, the higher the transversal strength of heat cured acrylic resin.

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Influence of Resin Cements on the Tension Force of Cast Frameworks Made by the Technique of Framework Cemented on Prepared Abutments

Brazilian Dental Journal ◽

10.1590/0103-6440201302423 ◽

2015 ◽

Vol 26 (4) ◽

pp. 390-392

Author(s):

Ana Paula Perroni ◽

Érica Alves Gomes ◽

Amália Machado Bielemann ◽

Bruna Baseggio ◽

Leonardo Federizzi ◽

...

Keyword(s):

Tensile Force ◽

Testing Machine ◽

Acrylic Resin ◽

Tension Force ◽

Polymerization Process ◽

Resin Cements ◽

Universal Testing ◽

Significant Difference ◽

Positive Results ◽

One Way Anova

<p>This study evaluated the tension force of cast frameworks made by the technique of framework cemented on prepared abutments using two different resin cements. Forty multi-unit abutment analogs were individually fixed with chemically cured acrylic resin inside PVC cylinders using a parallelometer. Brass cylindrical abutments were tightened to the multi-unit abutments to be used as spacers and then castable UCLA abutments were positioned above. These abutments were cast with Ni-Cr and then divided into 4 groups (n=10): cemented with RelyX U100(r); cemented with RelyX U100(r) and simulation of acrylic resin polymerization process; cemented with Multilink(r); and cemented with Multilink(r) and simulation of acrylic resin polymerization process. Abutments were cemented according to manufacturers' instructions. In a universal testing machine, tensile strength was applied in the direction of the long axis of the abutments at 1 mm/min crosshead speed until displacement of the luted abutments was obtained. The values of maximum tensile force (N) required for the displacement of the luted abutments were tabulated and analyzed statistically by one-way ANOVA with a 95% confidence level. No statistically significant difference was found among the groups (p>0.05). There was an increase in mean tension force when the specimens were subjected to the simulation of acrylic resin polymerization process, but the results did not differ statistically. Both resin cements presented positive results as regards the retention of luted abutments on their respective multi-unit abutments. Both materials may be indicated for the technique of framework cemented on prepared abutments when professionals pursuit better adaptation of implant-supported frameworks.</p>

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Pengaruh volumetrik e-glass fiber terhadap kekuatan transversal reparasi plat gigi tiruan resin akrilik

Majalah Kedokteran Gigi Indonesia ◽

10.22146/majkedgiind.10734 ◽

2017 ◽

Vol 2 (1) ◽

pp. 40

Author(s):

Pramudya Aditama ◽

Erwan Sugiatno ◽

Muhamad Rifqi Tri Nuryanto

Keyword(s):

Glass Fiber ◽

Glass Fibers ◽

Testing Machine ◽

Acrylic Resin ◽

Universal Testing Machine ◽

Transverse Strength ◽

Universal Testing ◽

Group I ◽

Denture Plate ◽

Significant Difference

The effect of e-glass fiber volumetric on transverse strength of an acrylic resin denture plate repair. Acrylic resin is the most commonly material for the denture base. A disadvantage of acrylic resin is that it is easily to be cracked. One of the ways to resolve this problem is by adding the E-glass fibers. The purpose of this research was to find out the effect of volumetric E-glass fiber on transverse strength of an acrylic resin denture plate repair. The experiment involved thirty plates of heat cured acrylic with the dimensions of 65 × 10 × 2.5 mm. The specimens were prepared to create a 3-mm gap and 45° bevel. Subjects were divided in to 3 groups, each of which contained 10. Group I (control) was with no fiber reinforcement, group II was reinforced with 3.7vol % E-glass fiber, and group III was reinforced with 7.4 volume % E-glass fiber. All plates were soaked in distillation water for one day at 37 °C. Plates were tested for transverse strength with Universal Testing Machine and all data obtained was analyzed with one way anova at 95% confidence level (α= 0.05). The significant difference was found between the transversal force of acrylic resin plat enforced with fiber and other group without being reinforced with fibers (p<0.05). Group reinforced with 7.4 vol % E-glass fibers showed a significant difference (higher) than the group reinforced with 3.7 volume % fibers. The addition of E-glass fibers in an acrylic resin plate repair material increased the transverse strength. The increase in volumetric fibers might improve the transverse strength of an acrylic resin plate repair material.ABSTRAKResin akrilik merupakan bahan yang sering digunakan dalam pembuatan basis gigi tiruan. Kekurangan dari bahan resin akrilik adalah mudah patah. Salah satu cara yang dapat digunakan untuk mengatasi masalah tersebut adalah dengan menambahkan E-glass fiber. Tujuan untuk mengetahui pengaruh volumetrik E-glass fiber terhadap kekuatan transversal reparasi plat gigi tiruan resin akrilik. Penelitian ini menggunakan tiga puluh plat resin akrilik kuring panas dengan ukuran 65 × 10 × 2,5 mm. Spesimen dipreparasi untuk membentuk jarak 3 mm dan sudut bevel 45°. Subjek kemudian dibagi menjadi 3 kelompok, setiap kelompok terdiri dari 10 plat. Kelompok I (kontrol) tanpa diberikan penguat fiber, kelompok II diperkuat dengan 3,7 vol % E-glass  ber, dan kelompok III diperkuat dengan 7,4 vol % E-glass fiber. Seluruh plat kemudian direndam dalam air destilasi selama satu hari pada suhu 37 °C. Plat resin akrilik kemudian diuji menggunakan Universal Testing Machine untuk mengetahui kekuatan transversal dan data yang didapatkan dianalisis menggunakan Anova satu jalur dengan tingkat kepercayaan 95% (α=0,05). Hasil menunjukkan terdapat perbedaan signifikan antara kekuatan transversal plat resin akrilik yang diperkuat dengan fiber dengan kelompok tanpa diperkuat fiber (p < 0,05). Kelompok yang diperkuat dengan 7,4 vol % E-glass fiber menunjukkan perbedaan signi kan (lebih tinggi) dibandingkan kelompok yang diperkuat dengan 3,7 vol % fiber. Kesimpulan bahwa peningkatan volume dari E-glass fiber dapat meningkatkan kekuatan transversal reparasi plat gigi tiruan resin akrilik.

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Effect of Insertion and Removal of Tooth Supported Overdentures on Retention Strength and Fatigue Resistance of Two Commercially Available Attachment Systems

International Journal of Prosthodontics and Restorative Dentistry ◽

10.5005/jp-journals-10019-1047 ◽

2012 ◽

Vol 2 (2) ◽

pp. 47-51

Author(s):

Satyabodh S Guttal ◽

Sagar Abhichandani

Keyword(s):

Fatigue Test ◽

Fatigue Resistance ◽

Testing Machine ◽

Acrylic Resin ◽

Graphical Analysis ◽

Universal Testing ◽

Female Component ◽

Number Of Cycles ◽

One Way Anova ◽

Retention Strength

ABSTRACT Purpose The main problem with semiprecision attachment retained prosthesis is that they need frequent servicing in terms of replacing the female component. There is a need for a study to assess the life span and frequency of replacement of elastic components in the attachment systems. Aim The aim of the study was to test the retention strength and fatigue resistance of Rhein OT cap and Ceka sagix attachment systems fabricated on the models. Materials and methods Rhein OT cap (micro) and Ceka sagix attachments were procured. Acrylic resin mandibular models fabricated with teeth embedded at overdenture positions. Bar framework with attachments were cast and cemented on the model. Denture fabricated on this model was subjected to universal testing machine (UTM Instron 5900 series) for retention and fatigue test. The retention strength was measured at various cycles namely 1,440, 2,880, 4,320 and 5,760 cycles to check for the loss of retention and development of fatigue on the basis of average number of removals and placements per day for 1,2,3 and 4 years, respectively. The values of both the attachment systems were recorded at the respective cycles and a graphical analysis was carried out representing the retention loss and development of fatigue. Results One-way ANOVA was used as part of the statistical analysis to compare the retention strength and fatigue resistance of both the attachment systems used. The results obtained proved that the retention values of both the attachment systems on tooth supported overdentures had a significant variation as they were subjected to increased number of cycles. Conclusion Sagix and Rhein attachment systems showed adequate retention values up to the first 2 to 3 years (2,880- 4,320 cycles). Fatigue test simulating 4 years of denture insertion and removal did cause subsequent reduction in the retention values but no component fracture of attachment systems. How to cite this article Guttal SS, Nadiger RK, Abhichandani S. Effect of Insertion and Removal of Tooth Supported Overdentures on Retention Strength and Fatigue Resistance of Two Commercially Available Attachment Systems. Int J Prosthodont Restor Dent 2012;2(2):47-51.

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Load-Application Devices: A Comparative Strain Gauge Analysis

Brazilian Dental Journal ◽

10.1590/0103-6440201300321 ◽

2015 ◽

Vol 26 (3) ◽

pp. 258-262 ◽

Cited By ~ 1

Author(s):

Renato Sussumu Nishioka ◽

Luis Gustavo Oliveira de Vasconcellos ◽

Renata Pilli Jóias ◽

Sigmar de Mello Rode

Keyword(s):

Strain Gauge ◽

Repeated Measures ◽

Testing Machine ◽

Acrylic Resin ◽

Load Application ◽

Chromium Alloy ◽

Axial Loads ◽

Nickel Chromium ◽

Universal Testing ◽

Significant Difference

In view of the low loading values commonly employed in dentistry, a load-application device (LAD) was developed as option to the universal testing machine (UTM), using strain gauge analysis. The aim of this study was to develop a load-application device (LAD) and compare the LAD with the UTM apparatus under axial and non-axial loads. An external hexagonal implant was inserted into a polyurethane block and one EsthetiCone abutment was connected to the implant. A plastic prosthetic cylinder was screwed onto the abutment and a conical pattern crown was fabricated using acrylic resin. An impression was made and ten identical standard acrylic resin patterns were obtained from the crown impression, which were cast in nickel-chromium alloy (n=10). Four strain gauges were bonded diametrically around the implant. The specimens were subjected to central (C) and lateral (L) axial loads of 30 kgf, on both devices: G1: LAD/C; G2: LAD/L; G3: UTM/C; G4: UTM/L. The data (με) were statistically analyzed by repeated measures ANOVA and Tukey's test (p<0.05). No statistically significant difference was found between the UTM and LAD devices, regardless of the type of load. It was concluded that the LAD is a reliable alternative, which induces microstrains to implants similar to those obtained with the UTM.

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The Effect of Thermoforming on Tear Strength of Ethylene Vinyl Acetate Mouthguard Material in Various Thicknesses

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.751.657 ◽

2017 ◽

Vol 751 ◽

pp. 657-662

Author(s):

Phakphum Srinuan ◽

Jeerapatr O. Baiyokvichit ◽

Rasana Boonpeng ◽

Tanapol Wongwisatekit ◽

Pacharaporn Pattanasukwasan ◽

...

Keyword(s):

Vinyl Acetate ◽

Testing Machine ◽

Ethylene Vinyl Acetate ◽

Strength Test ◽

Tear Strength ◽

Universal Testing ◽

Significant Difference ◽

The Mean ◽

Thermoforming Process ◽

One Way Anova

The effect of thermoforming on the tear strength of ethylene vinyl acetate (EVA) mouthguard material (Bioplast®) has not been widely investigated. The present study compared the tear strengths of non-processed and processed EVA specimens in various thicknesses. Two groups of EVA sheet (non-processed and processed) in three different thicknesses of 3, 4 and 5 mm were used in specimen fabrication. The processed EVA sheets were achieved by forming the EVA sheet on the cylindrical stone model with the pressure-molding device (Biostar®). Twelve of tear strength specimens of non-processed and processed group in each thickness were prepared following the modified ASTM D 624-00 guideline. The tear strength test was conducted using universal testing machine (Lloyd® 1K series) with the speed of 500 mm/min. The mean thickness and tear strength of the non-processed and processed specimens in each thickness were compared using independent T-test. The differences in the mean tear strength for each thickness of non-processed and process specimens were determined using one-way ANOVA. The mean tear strength and mean thickness of processed EVA specimens was significantly lower than the non-processed EVA specimens for every thickness (P ≤ 0.05). There was no significant difference in the mean tear strength of EVA specimens among each thickness in both non-processed and processed groups. It can be concluded that the thermoforming process has the significant effect on the tear strength of the EVA mouthguard material formed by pressure molding device in every thicknesses. The tear strength of processed specimens were significant lower than the non-processed. Thus, it is more relevant for testing properties of the processed mouthguard material that the mouthguard material before processing.

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Ceramic Bonding to Biocompatible Titanium Alloys Obtained by Powder Metallurgy

Materials Science Forum ◽

10.4028/www.scientific.net/msf.530-531.605 ◽

2006 ◽

Vol 530-531 ◽

pp. 605-611

Author(s):

M.C. Bottino ◽

D.K. Oyafuso ◽

Paulo Guilherme Coelho ◽

Elisa B. Taddei ◽

Vinicius André Rodrigues Henriques ◽

...

Keyword(s):

Bond Strength ◽

Titanium Alloys ◽

Shear Bond Strength ◽

Microstructural Analysis ◽

Testing Machine ◽

Phase Identification ◽

Base Metals ◽

Blended Elemental ◽

Universal Testing ◽

One Way Anova

The shear bond strength between a ceramic material (Titankeramik®, Vita Zahnfabrik, Germany) and two biocompatible titanium alloys was investigated. Ti-13%Nb-13%Zr (TNZ) and Ti-35%Nb-7%Zr-5%Ta (TNZT) alloys were obtained based on the blended elemental technique followed by a sequence of cold uniaxial and isostatic pressing and sintering. Characterization involved microstructural analysis (SEM) and crystalline phase identification (XRD). Subsequently, samples were machined to 4 x 4 mm with a base of 5 x 1 mm. The base metals were blasted with Al2O3 particles followed by the application of a coupling agent and opaque ceramic. After ceramic firing, the specimens were loaded in a universal testing machine (0,5mm/min). XRD revealed the presence of α and β-phases for TNZ, and peaks related to β phases and Nb and Ta for the TNZT alloy. SEM evaluation (TNZ) depicted remaining pores and biphasic microstructure formation. SEM micrographs of the TNZT alloy revealed good densification and a homogeneous β structure. Shear bond strength data (MPa) were statistically analyzed (one-way ANOVA and Tukey test, α=.05) revealing that TNZT (37.6 ± 2.91) presented significant higher values (p=0.0002) compared to TNZ (26.03 ± 2.92). In conclusion, it seems that Ti alloy composition plays a significant role on ceramic bonding.

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