Background: The aim of this study was to evaluate the effect of adding four different monomers on the flexural strength, elastic modulus, impact strength and residual monomer content of denture base resins polymerized by copolymerization mechanism. Methods: Butyl methacrylate (BMA), Isobutyl mathacrylate (IBMA), 2-hydroxyethyl methacrylate (HEMA) and methacryl-polyhedral silses quioxane (POSS-MA) were added to monomers of conventional heat (HP) and microwave polymerized (MP) polymethyl methacrylate (PMMA) resin at the concentrations of 2%, 5% and 10% per volume. The flexural strength, elastic modulus and impact strength of specimens were measured with an universal testing machine and Charpy-type impact tester. Residual monomer contents were determined by high performance liquid chromatography (HPLC) method. Results: 10% IBMA and 10% HEMA enhanced the flexural strength of HP resin. For the elastic modulus of MP resin, significant differences observed between the control group and 2 and 5% IBMA, 5 and 10% HEMA, and 5% POSS-MA groups (P
Amaç: Bu çalışmanın amacı dört farklı monomer eklenerek kopolimerizasyon mekanizmasıyla polimerize olmuş protez kaide rezinlerinin bükülme dayanımı, elastik modulus, çarpma dayanımı ve artık monomer içeriğinin değerlendirilmesidir. Gereç ve Yöntemler: Bütil metakrilat (BMA), isobütil metakrilat (IBMA), 2-hidroksietil metakrilat (HEMA) ve metakril-polihedral silseskioksan (POSS-MA) hacimce %2, %5 ve %10 konsantrasyonlarında konvansiyonel ısı (HP) ve mikrodalga (MP) akrilik monomerlerine ilave edilmiştir. Universal test cihazı ve Charpy tip çarpma test cihazı ile örneklerin bükülme dayanımı, elastik modulusu ve çarpma dayanımı ölçülmüştür. Yüksek performanslı sıvı kromatografisi (HPLC) metoduyla artık monomer içerikleri belirlenmiştir. Bulgular: %10 IBMA ve %10 HEMA, HP rezinlerin bükülme dayanımını artırmıştır. MP rezin grubunun elastik modulusu için kontrol grubu ile %2 ve %5 IBMA, %5 ve %10 HEMA ve %5 POSS-MA grupları arasında anlamlı farklılıklar gözlenmiştir (P
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Jagger DC, Harrison A, Jandt KD. The reinforcement of dentures. J Oral Rehabil 1999; 26(3): 185-94.
Nishii M. Curing of denture base resins with microwave irradiation: with particular reference to heat-curing resins. J Osaka Dent Univ 1968; 2(1): 23-40.
Ayaz EA, Durkan R, Bagis B. The effect of acrylamide incorporation on the thermal and physical properties of denture resins. J Adv Prosthodont 2013; 5(2): 110-7.
Polyzois G, Andreopoulos AG, Lagauvardos PE. Acrylic resin denture repair with adhesive resin and metal wires: effects on strength parameters. J Prosthet Dent 1996; 75(4): 381-7.
Köroğlu A, Özdemir T, Usanmaz A. Comparative study of the mechanical properties of fiber-reinforced denture base resin. J App Polymer Sci 2009; 113(2): 716-20.
Sahin O, Ozdemir AK, Turgut M, Boztug A, Sumer Z. Investigation of flexural strength and cytotoxicity of acrylic resin copolymers by using different polymerization methods. J Adv Prosthodont 2015; 7(2): 98-107.
Rodford RA. Further development and evaluation of high impact strength denture base materials. J Dent 1990; 18(3): 151-7.
Cunha TM, Regis RR, Bonatti MR, de Souza RF. Influence of incorporation of fluoroalkyl methacrylates on roughness and flexural strength of a denture base acrylic resin. J Appl Oral Sci 2009; 17(2): 103-7.
Hogt AH, Dankert J, Feijen J. Adhesion of coagulasenegative staphylococci to methacrylate polymers and copolymers. J Biomed Mater Res 1986; 20(4): 533-45.
Hamza TA, Johnston WM, Schricker SR. Effect of polyhedral silsesquioxane (POSS) on the flexural strength and color of interim materials. J Prosthet Dent 2014; 112(2): 228-34.
Vallittu PK, Ruyter IE, Buykuilmaz S. Effect of polymerization temperature and time on the residual monomer content of denture base polymers. Eur J Oral Sci 1998; 106(1): 588-93.
Doğan A, Bek B, Çevik NN, Usanmaz A. The effect of preparation conditions of acrylic denture base materials on the level of residual monomer, mechanical properties and water absorption. J Dent 1995; 23(5): 313-8.
Bartoloni JA, Murchison DF, Wofford DT, Sarkar NK. Degree of conversion in denture base materials for varied polymerization techniques. J Oral Rehabil 2000; 27(6): 488-93.
Mohamed SH, Al-Jadi AM, Ajaal T. Using of HPLC analysis for evaluation of residual monomer content in denture base materials and their effect on mechanical properties. J Phy Sci 2008; 19(2): 127-35.
Tsuchiya H, Hoshino Y, Kato H, Takagi N. Flow injection analysis of formaldehyde leached from denture-base acrylic resins. J Dent 1993; 21(4): 240-3.
American Dental Association (ADA), 1999. Specifications for denture base polymer number 12: 1999 (Reaffirmed 2008).
International Standard Organization, 1998. Specifications for denture base polymers; ISO 1567: 1998.
Ayaz EA, Durkan R. Influence of acrylamide monomer addition to the acrylic denture-base resins on mechanical and physical properties. Int J Oral Sci 2013; 5(4): 229-35.
Kurata S, Morishita K, Shimoyama K, Umemoto K. Basic study on the application of novel functional monomers to a denture base resin. Dent Mater J 2008; 27(2); 273-7.
Matsukawa S, Hayakawa T, Nemoto K. Development of high-toughness resin for dental applications. Dent Mater 1994; 10(6): 343-6.
. Wu X, Sun Y, Xie W, Liu Y, Song X. Development of novel dental nanocomposites reinforced with polyhedral oligomeric silsesquioxane (POSS). Dent Mater 2010; 26(5): 456-62.
Ayandele E, Sarkar B, Alexandridis P. Polyhedral oligomeric silsesquioxane (POSS)containing polymer nanocomposites. Nanomaterials 2012; 2(4): 445-75.
Zhang W, Müller AHE. Architecture, selfassembly and properties of well-defined hybrid polymers based on polyhedral oligomeric silsesquioxane (POSS). Progress in Polymer Science 2013; 38(8): 1121-62.
Wheeler PA, Fu BX, Lichtenhan JD, Weitao J, Mathias LJ. Incorporation of metallic POSS, POSS copolymers, and new functionalized POSS compounds into commercial dental resins. J App Poly Sci 2006; 102(3): 2856-62.
Gao F, Tong Y, Schricker SR, Culbertson BM. Evaluation of neat resins based on methacrylates modified with methacryl-POSS, as potential organic-inorganic hybrids for formulating dental restoratives. Polym Adv Technol 2001; 12(6): 355-60.
. Lai CP, Tsai MH, Chen M, Chang HS, Tay HH. Morphology and properties of denture acrylic resins cured by microwave energy and conventional water bath. Dent Mater 2004; 20(2): 133-41.
Azzarri MJ, Cortizo MS, Alessandrini JL. Effect of the curing conditions on the properties of an acrylic denture bas eresin microwave-polymerised. J Dent 2003; 31(7): 463-8.
Köroğlu A, Özdemir T, Pamir AD, Usanmaz A. Residual acrylic monomer content of denture base resins with different fiber systems. J App Poly Sci 2012; 125(1): 471-6.
Clarke RL. Dynamic mechanical thermal analysis of dental polymers: III. Heterocyclic methacrylates. Biomaterials 1989; 10(9): 630-3.
.Vallittu PK, Narva K. Impact strength of a modified continuous glass-fiber poly (methyl methacrylate). Int J Prosthodont 1997; 10(2): 142-8.
Çelebi N, Yüzügüllü B, Canay Ş, Yücel Ü. Effect of polymerization methods on the residual monomer level of acrylic resin denture base polymers. Polym Adv Technol 2008; 19(3): 201-6.
Kedjarune U, Charoenworaluk N, Koontongkaew S. Release of methyl methacrylate from heat-cured and autopolymerized resins: cytotoxicity testing related to residual monomer. Aus Dent J 1994; 44(1): 25-30.
Hoffman AS. Hydrogels for biomedical applications. Adv Drug Deliv Rev 2002; 54(1): 3-12.