[Home ] [Archive]    
:: Main :: About :: Current Issue :: Archive :: Search :: Submit ::
:: Volume 25, Issue 4 (10-2013) ::
J Iran Dent Assoc 2013, 25(4): 242-248 Back to browse issues page
The Effect of Microwave Disinfection on Dimensional Stability and Flexural Strength of Acrylic Resins
Omid Tavakkol1, Ehsan Farjood2, Venos Mortazavi3, Mahroo Vojdani *4
1- Prosthodontist
2- Postgraduate Student, Department of Prosthodontic, School of Dentistry, Shiraz University of Medical Sciences, Shiraz, Iran
3- Specialist in Operative Dentistry
4- Professor, Biomaterial Research Center, School of Dentistry, Shiraz University of Medical Sciences, Shiraz, Iran , vojdanim@yahoo.com
Abstract:   (8272 Views)

  Background and Aim: Several studies have evaluated the effect of microwave radiation on physical properties of acrylic resins. However, due to the recent introduction of heat-cure and cold-cure acrylic resins into the dental market and rapid popularity of cold-cure resins with less distortion in denture base, the present study sought to assess the effect of microwave disinfection on dimensional stability and flexural strength of two recently introduced heat-cure (Ivoclar) and cold-cure (FuturaGen) acrylic resins .

  Materials and Methods : In this laboratory study, acrylic models were fabricated of an edentulous maxillary model using Ivoclar and FuturaGen acrylic resins. Three reference points were marked on the model: two in the back and one in the front of the edentulous arch. These reference points were used for the measurement of dimensional stability in the anteroposterior and cross-arch dimensions. Ten specimens of each acrylic resin were not disinfected. Ten samples were subjected to two 3 min cycles of microwave disinfection with 600 watt power. Distances between the reference points were measured by a Profile Projector. To evaluate flexural strength, a metal mould measuring 64x10x3.3 mm was used for the fabrication of resin specimens. Similar to what was done for dimensional stability testing, 10 specimens of each acrylic resin were not disinfected and 10 other samples were subjected to 3-point bending test after disinfection. Data were compared and statistically analyzed using Mann-Whitney U test .

  Results: The mean difference in anteroposterior and cross-arch dimensions revealed that two cycles of microwave disinfection of Ivoclar and FuturaGen acrylic resins did not have a significant effect on their dimensional stability (P>0.017). The mean and standard deviation of the flexural strength of FuturaGen acrylic resin before and after disinfection was 76.86±16.80 and 70.18±8.48, respectively. These values for Ivoclar acrylic resin were 85.92±12.23 and 81.91±6.59, respectively. Two cycles of disinfection with microwave did not cause a significant effect on flexural strength of the two understudy acrylic resins (P>0.05) .

  Conclusion: Two cycles of microwave disinfection had no negative effect on dimensional stability or flexural strength of FuturaGen and Ivoclar acrylic resins .

Keywords: Acrylic resin, disinfection, microwave
Full-Text [PDF 197 kb]   (2360 Downloads)    
Type of Study: Original | Subject: Prosthodontics
1. Sadamori S, Kotani H, Hamada T. The usage peviod of dentures and their residual monomer contents. J Prosthet Dent. 1992 Aug;68(2):374-376.
2. Brill N, Tryde G, Stoltze K, El Ghamrawy EA. Ecologic changes in the oral cavity cavsed by removable partial dentures. J Prosthet Dent. 1977 Aug; 38(2):138-148.
3. Glass RT, Bullard JW, Hadley CS, Mix EW, Convad RS. Partial spectrum of microorganisms found in dentures and passible disease implica-tions. J Am Osteopath Ass. 2001 Feb;101(2):92-94.
4. Pavarina AC, Pizzolitto AC, Machado AL, Ver-gani CE, Giampaolo ET. An infection control protocol: effectiveness of immersion solutions to reduce the microbial growth on dental pros-theses. J Oral Rehabil. 2003 May;30(5):532-536.
5. Zarb GA, Mackay HF. The partially edentulous patient.I. The biologic price of prosthodontic intervention. Aust Dent J. 1980 Jun;25(3):63-68.
6. Powell GL, Runnells RD, Saxon BA, Whisehant BK. The presence and identification of organ-isms transmitted to dental laboratories. J Pros-thet Dent. 1940 Aug;64(2):235-234.
7. Federation Dentaire International. A revision of technical report No 10. Recommendations for hy-giene in dental practice, including treatment for the infections patient. Int Dent J. 1987 Jun; 37(2):142-145.
8. Henderson CW, Schwartz RS, Herdold ET, Mayhew RB. Evaluation of the barrier system, an infection control system for the dental labor-atory. J Prosthe Dent. 1987 Oct; 58(4):517-521.
9. Lin JJ, Cameron SM, Runyan DA, Craft DW. Disinfection of denture base acrylic resin. J Prosthe Dent. 1999 Feb; 81(2):202-206.
10. Shen C, Javid NS, Colazzi FA. The effect of glutaraldehyde base disinfectants on denture base resins. J Prosthet Dent. 1989 May;61(5):583-589.
11. Asad T, Wattkinson AC, Huggett R. The effect of varions disinfectan solutions on the surface hardness of an acrylic resin denture base mate-rial. Int J Prosthodont. 1993 Jan-Feb;6(1):9-12.
12. Azeredo A, Machado AL, Vergani CE, Giam-paolo ET, Pavarina AC, Magnani R. Effect of disinfectants on the hardness and roughness of reline acrylic resins. J Prosthod. 2006 Jul-Aug; 15 (4):235-242.
13. Weiger R, Kuhn A, Lost C. Effect of various types of sodium perborate on the PH of bleach-ing agents. J Endod. 1993 May;19(5):239-241.
14. Rodrigus Garcia RC, Joane Augusto de S Jr, Rached RN, Del Bel Cyry AA. Effect of den-ture cleansers on the surface roughness and hardness of a microwave – cured acrylic resin and dental alloys. J Prosthod. 2004 Sept; 13(3):173-178.
15. Molinari JA, Runnells RR. Role of disinfectants in infections control. Dent Clin North Am. 1991 Apr; 35(2):323-337.
16. Ma T, Johnson GH, Gordon GE. Effects of chemical disinfectants on the surface character-istics and color of denture resins. J Prosthet Dent. 1997 Feb; 77(2):197-204.
17. Ma T, Johnson GH, Gordon GE. Effects of chemical disinfectants on the surface character-istics and color of denture resins.J Prosthet Dent. 1997 Feb;77(2):197-204.
18. Sagripanti JL, Bonifacino A. Cytotoxicity of liquid disinfectants. Surg Infect. 2000Apr;1(1):3-14.
19. Connor C. Cross– contamination control in prosthodontic practice. Int J Prosth. 1991 Jul-Aug; 4(4):337-344.
20. Depaola LG, Minah GE. Isolation of patho-genic microorganisms from dentures and den-ture-soaking containers of myelo suppressed cancer patients. J Prosth Dent. 1983 Jan; 49(1):20-24.
21. Webb BC, Thomas CJ, Harty DW, Willcox MD. Effectiveness at two methods of denture sterilization. J Oral Rehabil. 1998 Jun;25(6):416-423.
22. Baysan A, Whitley R, Wright PS. Use of mi-crowave energy to disinfect a long-term soft lining material contaminated with candida albi-cans or staphylococcus aureus. J Prosthet Dent. 1998 Apr; 79(4):454-8.
23. Dixon DL, Breeding LC, Faler TA. Micro-wave disinfection of denture base materials colonized with candida albicans. J Prosthet Dent. 1999 Feb; 81(2):207-214.
24. Salim S, Sadamori S, Hamada T. The dimen-sional accuracy of rectangular acrylic resin specimens cured by three denture base pro-cessing methods. J Prosthet Dent. 1992 Jun; 67(6):879-881.
25. Rohrer MD, Bulard RA. Microwave sterili-zation. J Am Dent Ass. 1985 Feb;110(2):194-198.
26. Burns DRm Kazanoglu A, Moon PC, Gun Solley JC. Dimensional stability of acrylic resin materials after microwave sterilization. Int J Prosthod. 1990 Sep-Oct; 3(5):489-493.
27. Consani RLX, Azevedo DD, Mesquita MF, Mendes WB, Saquy PC. Effect of repeated dis-infection by microwave energy on the physical and mechanical properties of denture base acrylic resins. Braz Dent J. 2009Jun; 20(2):132-137.
28. Polyzois GL, Zissis AJ, Yannikakis SA. The effect of Gluteraldehyde and microwave disin-fection on some properties of acrylic denture resin. Int J Prosthod. 1995 Mar-Apr;8(2):150-154.
29. Thomas CG, Webb BC. Microwaving of acrylic resin dentures. Eur J Prosthodont Restor Dent. 1995Jun;3(4):179-182.
30. Pavan S, Arioli Filho JN, Dos Santos PH, Mollo Fde A. Effect of microwave treatment on dimensional accuracy of maxillary acrylic resin den-ture base. Braz Dent J. 2005May-Aug; 16(2):119-123.
31. Sartori EA, Schmidt CB, Walber LF, Shinkai RS. Effect of microwave disinfection on den-ture base adaptation and resin surface rough-ness. Braz Dent J. 2006 Jul-Sept; 17(3):195-200.
32. Consani RLX, Mesquita MF, Nobilo MAA, Henrigues GEP. Influence of simulated micro-wave disinfection on completedenture base ad-aptation using different flask closure methods. J Prosthet Dent. 2007 Mar; 97(3):173-178.
33. Pavarina AC, Neppelenbroek KH, Guinesi AS, Vergani CE, Machado AC, Giampaolo ET. Effect of microwave disinfection on the flex-tural strength of hard chairside reline resins. J Dent. Oct; 33(9): 741-748.
34. Keenan PLJ, Radford DR, Clark RKF. Di-mensional change in complete dentures fabri-cated by injection molding and microwave processing. J Prosthet Dent. 2003 Jan; 89(1):37-44.
35. Parvizi A, Lindquist T, Schneider R, Wil-liamson D, Boyer D, Dawson DV. Comparison of the dimensional accuracy of injection-molded denture base materials to that of con-ventional pressure-pack acryilic resin. J Prosthet Dent. 2004 Jun; 13 (2):83-89.
36. Hugget R, Zissis A, Harrison A, Dennis A. Dimensional accuracy and stability of acrylic resin denture bases. J Prosthet Dent. 1992 Oct; 68(4): 634-40.
37. Latta GH, Bowles WF, Conkin BPS. Three-dimensional stability of new denture base resin systems. J Prosthet Dent. 1990 Jun;63(6):654-61.
38. Burns DRm Kazanoglu A, Moon PC, Gun Solley JC. Dimensional stability of acrylic resin materials after microwave sterilization. Int J Prosthodont. 1990 Sept-Oct; 3(5):489-493.
39. Seo RS, Murata H, Hong G, Vergani CE, Hamada T. The influence of thermal and me-chanical stresses on the strength of intact and relined denture bases. J Prosthet Dent. 2006 Jul;96(1):59-67.
40. Vallitue PK, Miettinen V, Alakuijala P. Re-sidual monomer content and its release into wa-ter from denture base materials. Dent Mater. 1995 Nov;11(6):338-42.
41. Kedjarune U, Charoenworaluk N, Koontongkaew S. Release of methyl methacrylate from heat-cured and autopolymerized resins: cytotoxicity testing related to residual monomers. Aust Dent J. 1999 Mar;44(1):25-30.
42. Urban VM, Machado AL, Oliviera RV, Ver-gani CE, Pavarina AC, Cass QB. Residual mon-omers of reline acrylic resins. Effect of water-bath and microwave post-polymerization treat-ments. Dent Mater. 2007 Mar; 23(3):363-368.
43. Farzin M, Safari S, Vojdani M. Bond strength and deflection of a hard chair side re-line material to two denture base resins. J Isfa-han Dent School. 2010Oct; 6(3):195-202.
Send email to the article author

Add your comments about this article
Your username or Email:


XML     Print

Download citation:
BibTeX | RIS | EndNote | Medlars | ProCite | Reference Manager | RefWorks
Send citation to:

Tavakkol O, Farjood E, Mortazavi V, Vojdani M. The Effect of Microwave Disinfection on Dimensional Stability and Flexural Strength of Acrylic Resins. J Iran Dent Assoc 2013; 25 (4) :242-248
URL: http://jida.ir/article-1-1508-en.html

Rights and permissions
Creative Commons License This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License.
Volume 25, Issue 4 (10-2013) Back to browse issues page
Journal of Iranian Dental Association


This work is licensed under a Creative Commons Attribution-NonCommercial 3.0 Unported License which allows users to read, copy, distribute and make derivative works for non-commercial purposes from the material, as long as the author of the original work is cited properly

Persian site map - English site map - Created in 0.05 seconds with 30 queries by YEKTAWEB 4570