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Mechanical and thermal properties of polyamide versus reinforced PMMA denture base materials.

Soygun K, Bolayir G, Boztug A - J Adv Prosthodont (2013)

Bottom Line: The data were analyzed by Kruskal-Wallis and Tukey tests for pairwise comparisons of the groups at the 0.05 level of significance.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.

View Article: PubMed Central - PubMed

Affiliation: Department of Prosthodontics, Faculty of Dentistry, Cumhuriyet University, Sivas, Turkey.

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.

No MeSH data available.


Related in: MedlinePlus

Stress-strain curves of the resin sample groups.
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Figure 1: Stress-strain curves of the resin sample groups.

Mentions: TMA analysis data are given in Table 3. Valplast material group had the highest mechanical resistance values (Fig. 1). Modulus of elasticity (E) values was obtained from the curvatures of the original linear sections of the stress-strain curves. Likewise, the coefficient of thermal elongation values (α) were acquired from the original linear sections of the temperature-strain curves (Fig. 2). And the vitreous transition temperature (Tg) values were obtained using the instant drop regions of the temperature-logE curves (Fig. 3). single climax observed in the thermo-mechanical curves, and thermo-mechanical parameters (Table 3) of the samples could be taken as an indication that the used fibers were compatible with the PMMA resin.


Mechanical and thermal properties of polyamide versus reinforced PMMA denture base materials.

Soygun K, Bolayir G, Boztug A - J Adv Prosthodont (2013)

Stress-strain curves of the resin sample groups.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC3675288&req=5

Figure 1: Stress-strain curves of the resin sample groups.
Mentions: TMA analysis data are given in Table 3. Valplast material group had the highest mechanical resistance values (Fig. 1). Modulus of elasticity (E) values was obtained from the curvatures of the original linear sections of the stress-strain curves. Likewise, the coefficient of thermal elongation values (α) were acquired from the original linear sections of the temperature-strain curves (Fig. 2). And the vitreous transition temperature (Tg) values were obtained using the instant drop regions of the temperature-logE curves (Fig. 3). single climax observed in the thermo-mechanical curves, and thermo-mechanical parameters (Table 3) of the samples could be taken as an indication that the used fibers were compatible with the PMMA resin.

Bottom Line: The data were analyzed by Kruskal-Wallis and Tukey tests for pairwise comparisons of the groups at the 0.05 level of significance.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.

View Article: PubMed Central - PubMed

Affiliation: Department of Prosthodontics, Faculty of Dentistry, Cumhuriyet University, Sivas, Turkey.

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.

No MeSH data available.


Related in: MedlinePlus