Influence of various metal oxides on mechanical and physical properties of heat-cured polymethyl methacrylate denture base resins (original) (raw)
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Aims: The study was conducted to modify heat cured acrylic resin denture base material with additives [flavoring agents (caramel, banana)], and plasticizer into a flexible heat cured acrylic resin as a Flexite thermoplastic material. Methods: One hundred ninety-five samples of heat cured acrylic resin (HCAR) that consist of control group and three types of additives with two concentrations 15%, and 20% [flavoring agents (caramel, banana)], and plasticizer di-butyl phthalate (DBP) addition to (HCAR) 20% group, plasticizer (DBP) addition to (HCAR) group, flavoring (caramel) addition to (HCAR) group, flavoring (banana) addition to (HCAR) group and flexite thermoplastic material group were prepared to examine tensile strength, water sorption, solubility, color change and dimensional accuracy. Results: Statistically significant differences were identified between groups with and without additives exhibited higher mean value of tensile strength of flexite thermoplastic group. Duncan's...
Al-Azhar Journal of Dental Science, 2018
Objective:The aim of this in vitro study was to compare some properties of polyamide(nylon) flexible and conventional heat cured acrylic resin denture base material. Material and Methods: 80 specimens were prepared according to the specific dimension for each test and allocated to two groups. Group (A) 40 specimens of conventional acrylic resin. Group (B) 40 specimens of polyamide denture base material. Results: Surface roughness and water sorption were tested for both groups. The data was collected and statistically analyzed. Conventional group showed significant higher roughness than polyamide group. Polyamide group showed non significant higher water sorption than conventional group. Conclusion: Polyamide denture base could be used as alternative material for conventional heat cured acrylic resin.
Modified Heat Cured Acrylic Resin Denture Base Material: Residual Monomer
Aims: to estimate the amounts of residual methyl methacrylate (MMA) of heat cured acrylic resin denture base material modified with Acrylic Acid (AA), Zinc Oxide (ZnO) and Zinc Diacrylate (ZDA) additives. Methods: thermally activated ZnO and ZDA powders were synthesized. Heat cured acrylic resin denture base material had modified by adding 5% or 10% by weight from each of AA, ZnO and ZDA. High Performance Liquid Chromatography (HPLC) was used as the analytical monitoring method to quantify the residual MMA in the cured samples. One-way ANOVA test was used to compare the results. Results: minimum amounts of residual MMA were estimated in heat cured acrylic resin modified by AA, while the addition of each of ZnO and ZDA to heat cured resin results in statistically significant larger amounts (p≤0.05) of residual MMA than the control sample. The analyzed residual MMA quantities of all polymerized samples were lesser than ADA standardization (2.2% mass fraction). Conclusion: modifying heat cured acrylic resin with ZnO or ZDA additives result in larger residual MMA than modifying it with AA additive.
The effect of acrylamide incorporation on the thermal and physical properties of denture resins
The Journal of Advanced Prosthodontics, 2013
Polymethyl methacrylate (PMMA) is the most commonly used denture base material despite typically low in strength. The purpose of this study was to improve the physical properties of the PMMA based denture base resins (QC-20, ) by copolymerization mechanism. MATERIALS AND METHODS. Control group specimens were prepared according to the manufacturer recommendations. In the copolymer groups; resins were prepared with 5%, 10%, 15% and 20% acrylamide (AAm) (Merck, Hohenbrunn, Germany) content according to the moleculer weight ratio, respectively. Chemical structure was characterized by a Bruker Vertex-70 Fourier transform infrared spectroscopy (FTIR) (Bruker Optics Inc., Ettlingen, Germany). Hardness was determined using an universal hardness tester (Struers Duramin, Struers A/S, Ballerup, Denmark) equipped with a Vickers diamond penetrator. The glass transition temperature (T g ) of control and copolymers were evaluated by Perkin Elmer Diamond DSC (Perkin Elmer, Massachusetts,USA). Statistical analyses were carried out using the statistical package SPSS for Windows, version 15.0 (SPSS, Chicago, IL, USA). The results were tested regarding the normality of distribution with the Shapiro Wilk test. Data were analyzed using ANOVA with post-hoc Tukey test (P<.01). RESULTS. The copolymer synthesis was confirmed by FTIR spectroscopy. Glass transition temperature of the copolymer groups were higher than the control groups of the resins. The 10%, 15% and 20% copolymer groups of Stellon presented significantly higher than the control group in terms of hardness. 15% and 20% copolymer groups of Acron MC showed significantly higher hardness values when compared to the control group of the resin. Acrylamide addition did not affect the hardness of the QC-20 resin significantly. CONCLUSION. Within the limitation of this study, it can be concluded that copolymerization of PMMA with AAm increased the hardness value and glass transition temperature of PMMA denture base resins. [ J Adv Prosthodont 2013;5:110-7]
Effect of denture cleansers on physical properties of heat-polymerized acrylic resin
Journal of Prosthodontic Research, 2010
Purpose: This study aimed to measure the color change, surface roughness and flexural strength of heat-polymerized acrylic resin after its immersion in denture cleansers, simulating a 180-day use. Methods: Thirty disk-shaped (15 mm  4 mm) and 30 rectangular samples (65 mm  10 mm  3.3 mm) were prepared from heat-polymerized acrylic resin and immersed in Corega Tabs, Bony Plus, and distilled water. Color measurements (DE) were determined by a portable colorimeter. A surface analyzer was used to measure the roughness before and after immersion (DRa). The flexural strength (S) was measured using a 3-point bending test. The DE values were submitted to statistical analysis by the Kruskal-Wallis test, followed by Dunn's Multiple Comparisons test. The DRa and S values were submitted to statistical analysis by ANOVA, followed by a Student-Newman-Keuls test (a = .05). Results: The color changes were significantly higher for the Corega Tabs than for the control group. The mean DE values quantified by the National Bureau of Standards (NBS) were classified as Trace (0.0-0.5). The Bony Plus group had significantly higher surface roughness than the other groups. Corega Tabs and Bony Plus groups presented lower flexural strength than the control group. Conclusions: Although the color changes after the immersion in denture cleansers were clinically insignificant, the Corega Tabs group showed higher color differences. The Bony Plus group showed significantly increased surface roughness. Both effervescent tablets Corega Tabs and Bony Plus significantly diminished the flexural strength of the acrylic resin.
Evaluation of Surface hardness of Denture Base Acrylic Resin Modified with Different Techniques
Al-Rafidain Dental Journal
Aims: Evaluation of the surface hardness of heat-treated acrylic resin after modifying it with three different techniques. Materials and Methods: Heat cured acrylic resin was modified by: (a) The copolymerization of acrylic resin with 5% and 10% of acrylic acid (AA), (b) The addition of 5% and 10% thermally activated zinc oxide (ZnO) and (c) The chemical bonding or engagement of Zinc ions into the polymer chain by an organic link, zinc diacrylate (ZDA) in 5% and 10%, to get a copolymer. The acrylic specimens have dimensions of (30, 15 and 3) ± 0.2 mm. Surface hardness was determined using a Durometer (Shore D) hardness tester. Results: There was general increase of the s u r f a c e h a r d n e s s of the experimental (modified) groups. A statical significant increase in the hardness of both acrylic groups modified by 10% ZnO and 10% ZDA compared to the control group and the remaining modified samples. Conclusion: Two techniques had significantly improved the hardness of heat cured acrylic resin; either by adding 10% by weight of thermally activated ZnO or by copolymerizing it with 10% by weight of ZDA to get poly (methyl methacrylateco-zinc acrylate) copolymer.
2020
Background : Tooth loss is one of the effects of periodontal disease and dental caries. Tooth loss can be resolved by making a denture prosthesis. Several factors that influence society on denture use include aesthetic, social, func-tional, educational, and cultural factors. The large number of lost teeth will certainly increase the demand or desire to manufacture dentures to restore the function of the missing teeth. One of the materials that are often used in den-tures is acrylic resin. Acrylic resins frequently used for denture base materials are cold polymerized acrylic resin and hot polymerized acrylic resin. Cold polymerized acrylic resin uses chemical activation, and this type of resin is often used for denture repair materials. Denture repair aims to repair prostheses that have many fractures in the mid-line area. Chemical polymerization acrylic resin is often used as a repair material because it is easy to apply and can be done directly on the patient. This resin has a disa...
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Objective. This study aimed to investigate the effects of nanoparticles (zirconium dioxide (ZrO2), titanium dioxide (TiO2), and silicon dioxide (SiO2)) on the flexural strength, impact strength, hardness, and wear resistance of the acrylic resin denture base material. Materials and Methods. Acrylic resin specimens were fabricated in dimensions according to American Dental Association (ADA) specifications per test. Specimens were divided according to nanofiller into four groups; unmodified as control, ZrO2 (Z), TiO2, (T), and SiO2 (S) groups. Each one was subdivided into two subgroups according to nanoparticle concentrations; 3% and 7% (Z3, Z7, T3, T7, S3, and S7). A 3-point bending test, Charpy impact test, and Vickers hardness test were used for flexural strength, impact strength, and hardness measurements, respectively. Wear resistance was measured by the differences in surface roughness of tested specimens before and after the wear test. A scanning electron microscope was used to...
Denture Base Resins From Past to New Era
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