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CC BY-NC-ND 4.0 · Eur J Dent 2018; 12(01): 116-119
DOI: 10.4103/ejd.ejd_199_17
Original Article
Dental Investigation Society

Effect of heat polymerization conditions and microwave on the flexural strength of polymethyl methacrylate

Serhat Emre Ozkir
1   Department of Prosthodontics, Faculty of Dentistry, Afyon Kocatepe University, Afyonkarahisar, Turkiye,
,
Burak Yilmaz
2   Division of Restorative Sciences and Prosthodontics, College of Dentistry, The Ohio State University, Columbus, Ohio, USA,
,
Server Mutluay Unal
1   Department of Prosthodontics, Faculty of Dentistry, Afyon Kocatepe University, Afyonkarahisar, Turkiye,
,
Ahmet Culhaoglu
3   Department of Prosthodontics, Faculty of Dentistry, Kirikkale University, Kirikkale, Turkiye,
,
Isin Kurkcuoglu
4   Department of Prosthodontics, Faculty of Dentistry, Suleyman Demirel University, Isparta, Turkiye
› Author Affiliations
Further Information

Publication History

Publication Date:
13 September 2019 (online)

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ABSTRACT

Objective: The objective of this study is the effect of different heat polymerization conditions on the strength of polymethyl methacrylate (PMMA) resin base is unknown. Distinguishing one method that provides improved mechanical properties may be beneficial to the clinical success of complete and partial dentures and overdentures. The purpose of this study was to evaluate the effect of different polymerization methods on the flexural strength of a dental PMMA resin. Materials and Methods: Forty PMMA specimens (64 mm × 10 mm × 4 mm) were prepared with 4 different polymerization methods (n = 10); heat polymerization at 74°C for 9 h, at 100°C for 40 min, and with 620 kPa pressure at 100°C for 20 min. The remaining group of specimens was microwave polymerized at 180 W for 6 min. All specimens were thermocycled at 5°C and 55°C for 5000 times. Three-point flexure test was used to measure the flexural strength of specimens. One-way ANOVA and Tukey Honestly Significant Difference were applied to analyze the differences in flexural strengths (⍺ = 0.05). Results: The flexural strength of heat-polymerized groups was similar. The flexural strength of microwave polymerized group was significantly different and lower than the other groups (P < 0.05). Conclusion: Polymerizing conventional heat-polymerizing PMMA resin with microwave energy resulted in a significant decrease in flexural strength. The results of this study suggest that clinicians may benefit from using heat polymerization when processing PMMA denture bases instead of microvawe polymerization when tested brand is used.

Key words:

Flexural strength - microwave - polymethyl methacrylate - polymerization
 

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