An Autoclave Effect on the Powder of Poly Methylmethacrylate

Manar.N.Y. Nazhat¹, Tariq.Y.Q. Basshi¹ and Amer.A. Taqa^2,

¹Department of Prosthodontics, College of Dentistry, University of Mosul

²Department of Basic Sciences, College of Dentistry, University of Mosul

Cite this paper:
Manar.N.Y. Nazhat, Tariq.Y.Q. Basshi and Amer.A. Taqa. An Autoclave Effect on the Powder of Poly Methylmethacrylate. International Journal of Dental Sciences and Research. 2014; 2(3):69-72. doi: 10.12691/ijdsr-2-3-6

Abstract

Background: Although most of the physical and mechanical properties of denture base resin polymerized by the conventional heat polymerization have been studied, the effect of autoclave processing on these properties has not been fully determined. The effect of autoclave on acrylic powder has not studied before. Materials and methods: Vertex was the heat – cured acrylic denture base material included in this study. A total of 90 specimens were prepared, the specimens were grouped into three control groups of Vertex acrylic resin which(group A) as curing by conventional water- bath technique (74ºC for 90 minutes, then boil for 30 minutes, (group B) which curing by water- bath (100°C for 30 minutes), and (group C)which curing by autoclave (120 °C under 1.4 bar for 45 minutes). The other three groups of Vertex acrylic resin after treatment of powder by autoclave in 132 °C for 4 hours, and then grouped into (A1,B1 andC1) which curing as previously. To study the effect of treatment of powder of acrylic resin byautoclave and the effect of autoclave processing. Three tests were conducted surface roughness (profilometer tester), transverse strength (Instron universal testing machine), and surface hardness (Shore D). The results were analyzed to Descriptive Statistics and ANOVA test. Results: There were no significant differences in surface roughness in all studying groups. There was a highly significant difference in transverse strength test results between studying groups. There was a significant difference in surface hardness test results between studying groups. Conclusions: The treatment of powder of acrylic resin by autoclave had no significant differences in surface roughness, but had a highly significant Difference in transverse strength in all test results, and a significant difference in hardness surface test in group B1. The autoclave processing technique might also be a good alternative to the conventional water- bath processing technique.

Keywords:
autoclave transverse surface roughness hardness surface

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References:

[1]	Jagger DC, Jagger RG, Allen SM and Harrison A. An investigation into the transverse and impact strength of high strength denture base acrylic resin. Journal of Oral Rehabilitation. 2002:29(3):263-267
[2]	Nikawa H, Sadamori S, Hamada T, Satao N, Okuda K. Non specific adherence of Candida species to surface modified glass. J Med Vet Mycol 1989; 27: 269-271.
[3]	Nikawa H, Hamada T. Binding of salivary or serum proteins to Candida albicans in vitro. Arch Oral Biol 1990; 17: 138-144.
[4]	Mang TR Jr, Latta MA. Physical properties of four acrylic denture base resin. Journal Contemporary Dental Practice 2005; 15(6): 93-100.
[5]	Azzari MJ, Cortizo MS, Alessandrini JL. Effect of the curing conditions on the properties of an acrylic denture base resin microwave polymerized. J Dent ; 2003; 31: 463-468.
[6]	Banerjee R, Banerjee S, Prabhudesai PS, Bhide SV. Influence of the processing technique on the flexural fatigue strength of denture base resins: J Prosthet Dent 2010.21:391-395.
[7]	Memon MS, Yunus N, Abdul Razak AA, Some mechanical properties of a highly cross-linked, microwave polymerized, injection-molded denture base polymer. International Journal of Prosthodontics 2001.14(3): 214-218.
[8]	Whitehead SA, Shearer AC, Watts DC, Wilson NHF. Comparison of methods for measuring surface roughness of ceramic. J Oral Rehabil. 1995; 22: 421-427.
[9]	Lee SY, Lai YL, Hsu TS. Influence of polymerization conditions on monomer elution and micro-hardness of autopolymerized polymethyl methacrylate resin. EurJ Oral Sci. 2002; 110: 179-183.
[10]	Waters MG, Williams DW, Jagger RG, Lewis MAO. Adherance of Candida albicans to experimental denture soft lining materials. J Prosthet Dent 1997; 77: 306-312.
[11]	Ravnholt G, Kabber S. Surface roughness of oral mucosa and its reproduction in dental materials. J Dent 1994; 22: 169-174.
[12]	Craig RG. Restorative Dental Materials. 11th ed . St Louis, MO: Mosby; 2002: pp.87-88.
[13]	Anusavise KJ. Philips, Science of Dental Materials. 11th ed. St Louis, MO: Saundders; 2003: p.737.
[14]	Lai CP, Tsia MH, Chen M, Chang HS, Tay HH. Morphology and properties of denture acrylic resins cured by microwave energy and conventional water bath. Dental Materials 2004, 20(2): 133-141.
[15]	Ming XC, Changxi S, Weishou H. Rapid processing procedure for heat polymerization of poly (methylmethacrylate) in a pressure cooker with automatic controls. J Prosthet Dent 1996; 76: 445-7.
[16]	Azevado MJ, Machado AL, Vergani CE, Giampaolo ET, Pavarina AC. (2005): Hardness of denture base and hard chair – side reline acrylic resins. J Appl Oral Sci; 3: 291-5.