TODENTJ-25-03-2019_TODENTJ-3-137 1553505072 Bentham Open doi@benthamopen.net Bentham Open The Open Dentistry Journal TODENTJ 1874-2106 6 29 2009 3 1 Fernanda Faot Leonardo H V Panza Renata C M Rodrigues Garcia Altair Antoninha Del Bel Cury Objectives: This study evaluated the impact and flexural strength and analyzed the fracture behavior of acrylic resins. Methods: Eighteen rectangular specimens were fabricated of Lucitone 550, QC 20 (both unreinforced acrylic resins), Impact 1500 (extra strength impact), Impact 2000 (high impact) according to the manufacturers’ instructions. The impact strength was evaluated in notched specimens (50x6x4mm) and flexural strength in unotched (64x10x3.3mm), using three-point bending test, as well as, stress at yield, Young modulus and displacement at yield. Fragments from mechanical tests were observed by SEM. Data from impact strength, stress at yield and displacement at yield were analyzed by 1-way ANOVA and Tukey test (α=0.05). Young modulus values were analyzed by One-way ANOVA and Dunnett T3 multiple comparisons test (α=0.05). Results: Mean values of impact strength and stress at yield values were higher (P<.005) for Impact 2000 while Young modulus was higher (P<.05) for Lucitone 550; Impact 1500 and Impact 2000 showed significant values (P<.05) in the displacement at yield. Impact fractures of the all acrylic resins were brittle. Bending fractures of Lucitone 550 and Impact 2000 were brittle, QC 20 fractures were ductile and Impact 1500 showed brittle (75%) and ductile (25%) fractures. Conclusion: Within the limitations of this study, the Impact 2000 showed improved mechanical properties with high capacity of stress absorption and energy dissipation before the fracture. 6 29 2009 137 143 TODENTJ-3-137 1 10.2174/crossmark_policy opendentistryjournal.com benthamopen.com true Peer Reviewed Single blind Checked with iThenticate 2009-3-09 2009-4-09 2009-5-08 2009-6-29 http://creativecommons.org/licenses/by-nc/3.0/ 10.2174/1874210600903010137 1553505072 https://opendentistryjournal.com/VOLUME/3/PAGE/137/ https://opendentistryjournal.com/contents/volumes/V3/TODENTJ-3-137/TODENTJ-3-137.pdf https://opendentistryjournal.com/contents/volumes/V3/TODENTJ-3-137/TODENTJ-3-137.pdf https://opendentistryjournal.com/contents/volumes/V3/TODENTJ-3-137/TODENTJ-3-137.pdf https://opendentistryjournal.com/contents/volumes/V3/TODENTJ-3-137/TODENTJ-3-137.pdf https://opendentistryjournal.com/contents/volumes/V3/TODENTJ-3-137/TODENTJ-3-137.pdf https://opendentistryjournal.com/contents/volumes/V3/TODENTJ-3-137/TODENTJ-3-137.pdf https://opendentistryjournal.com/contents/volumes/V3/TODENTJ-3-137/TODENTJ-3-137.pdf https://opendentistryjournal.com/contents/volumes/V3/TODENTJ-3-137/TODENTJ-3-137.xml J Oral Maxillofac Implants Feine JS 17 601 2002 Feine JS, Carlsson GE, Awad MA, et al. The McGill consensus statement on overdentures. Mandibular two-implant overdentures as first choice standard of care for edentulous patients. Montreal, Quebec, May 24-25, 2002 J Oral Maxillofac Implants 2002; 17 (4) : 601-2. J Contemp Dent Pract Meng TR Jr 6 93 2005 Meng TR Jr, Latta MA. Physical properties of four acrylic denture base resins J Contemp Dent Pract 2005; 6 : 93-100. Dent Mat Caycik S 8 153 1992 Caycik S, Jagger RG. The effect of cross-linking chain length on mechanical properties of a dough-molded poly(methylmethacrylate) resin Dent Mat 1992; 8 : 153-7. J Biomater Appl Uzun G 17 19 2002 Uzun G, Hersek N. Comparison of the fracture resistance of six denture base acrylic resins J Biomater Appl 2002; 17 : 19-29. Int J Prosthodont Memon MS 14 214 2001 Memon MS, Yunus N, Razak AA. Some mechanical properties of a highly cross-linked, microwave-polymerized, injection-molded denture base polymer Int J Prosthodont 2001; 14 : 214-8. J Dent Rodford R 14 214 1986 Rodford R. The development of high impact strength denture-base materials J Dent 1986; 14 : 214-7. Polymer Cho KYJ 39 3073 1998 Cho KYJ, Park CE. The effect of rubber particle size on toughening behaviour of rubber-modified poly(methylmethacrylate) with different test methods Polymer 1998; 39 : 3073-81. J Oral Rehabil Jagger DC 29 263 2002 Jagger DC, Jagger RG, Allen SM, Harrison A. An investigation into the transverse and impact strength of "high strength" denture base acrylic resins J Oral Rehabil 2002; 29 : 263-7. J Dent Rodford RA 18 151 1990 Rodford RA. Further development and evaluation of high impact strength denture base materials J Dent 1990; 18 : 151-7. J Oral Rehabil Del Bel Cury AA 28 433 2001 Del Bel Cury AA, Rached RN, Ganzarolli SM. Microwave-cured acrylic resins and silicone-gypsum moulding technique J Oral Rehabil 2001; 28 : 433-8. International Organization for Standardization ISO 1567:1998 Dentistry: denture base polymers Geneva Switzerland 1998. J Prosthet Dent Faot F 96 367 2006 Faot F, Costa MA, Del Bel Cury AA. Rodrigues Garcia RCM. Impact strength and fracture morphology of denture acrylic resins J Prosthet Dent 2006; 96 : 367-73. J Oral Rehabil Jagger DC 26 185 1999 Jagger DC, Harrison A, Jandt KD. The reinforcement of dentures J Oral Rehabil 1999; 26 : 185-94. J Biomed Mater Res Stafford GD 14 359 1980 Stafford GD, Huggett R, Causton BE. Fracture toughness of denture base acrylics J Biomed Mater Res 1980; 14 : 359-71. Brown N. Yield behavior of polymers In: Brostow W, Corneliussen RD, Eds. Failure of plastics. New York: Hanser 1986; pp. 110-8. Int J Prosthodont Smith LT 5 315 1992 Smith LT, Powers JM, Ladd D. Mechanical properties of new denture resins polymerized by visible light, heat, and microwave energy Int J Prosthodont 1992; 5 : 315-20. J Dent Harrison A 6 299 1978 Harrison A, Huggett R, Jagger RC. The effect of a cross-linking agent on the abrasion resistance and impact strength of an acrylic resin denture base material J Dent 1978; 6 : 299-304. J Biomed Mater Res Hargreaves AS 15 757 1981 Hargreaves AS. The effect of the environment on the crack initiation toughness of dental poly(methyl methacrylate) J Biomed Mater Res 1981; 15 : 757-68. J Biomed Mater Res Kusy RP 9 89 1975 Kusy RP, Turner DT. Fractography of poly(methyl methacrylates) J Biomed Mater Res 1975; 9 : 89-98. J Oral Rehabil Vallittu PK 23 524 1996 Vallittu PK. Fracture surface characteristics of damaged acrylic-resin-based dentures as analysed by SEM-replica technique J Oral Rehabil 1996; 23 : 524-9.