Mechanical and thermal properties of polyamide versus reinforced PMMA denture base materials.
- Author:
Koray SOYGUN
1
;
Giray BOLAYIR
;
Ali BOZTUG
Author Information
- Publication Type:In Vitro ; Original Article
- Keywords: PMMA; Polyamide; Mechanical and thermal properties; Reinforced
- MeSH: Caprolactam; Denture Bases; Dentures; Elastic Modulus; Glass; Nylons; Polymers; Polymethyl Methacrylate
- From:The Journal of Advanced Prosthodontics 2013;5(2):153-160
- CountryRepublic of Korea
- Language:English
- Abstract: PURPOSE: This in vitro study intended to investigate the mechanical and thermal characteristics of Valplast, and of polymethyl methacrylate denture base resin in which different esthetic fibers (E-glass, nylon 6 or nylon 6.6) were added. MATERIALS AND METHODS: Five groups were formed: control (PMMA), PMMA-E glass, PMMA-nylon 6, PMMA-nylon 6.6 and Valplast resin. For the transverse strength test the specimens were prepared in accordance with ANSI/ADA specification No.12, and for the impact test ASTM D-256 standard were used. With the intent to evaluate the properties of transverse strength, the three-point bending (n=7) test instrument (Lloyd NK5, Lloyd Instruments Ltd, Fareham Hampshire, UK) was used at 5 mm/min. A Dynatup 9250 HV (Instron, UK) device was employed for the impact strength (n=7). All of the resin samples were tested by using thermo-mechanical analysis (Shimadzu TMA 50, Shimadzu, Japan). The data were analyzed by Kruskal-Wallis and Tukey tests for pairwise comparisons of the groups at the 0.05 level of significance. RESULTS: In all mechanical tests, the highest values were observed in Valplast group (transverse strength: 117.22 +/- 37.80 MPa, maximum deflection: 27.55 +/- 1.48 mm, impact strength: 0.76 +/- 0.03 kN). Upon examining the thermo-mechanical analysis data, it was seen that the E value of the control sample was 8.08 MPa, higher than that of the all other samples. CONCLUSION: Although Valplast denture material has good mechanical strength, its elastic modulus is not high enough to meet the standard of PMMA materials.
