Abstract
Poly-methyl methacrylate is a rigid material. It is generally observed that the impact and flexural strength of this material is not satisfactory and that is reflected in the continuous efforts to improve these mechanical properties. Hence there was a serious need to make another material which could overcome the limitations of the existing materials and could have better properties, like thermoplastic materials. The study was aimed to evaluate and compare the impact strength and the flexural strength of four different flexible denture base materials (thermoplastic denture base resins) with the conventional denture base material (high impact polymethyl-methacrylate). Two, machine made master moulds of metal blocks according to the size of sample holder of the equipment were prepared to test the impact and flexural strength. Total 40 samples, 10 for each group of flexible denture base materials namely: De-flex (Deflex, United Kingdom), Lucitone FRS (Densply, Germany), Valplast (Novoblast, USA), and Bre-flex (Bredent, Germany) in specially designed flask by injection molded process. For different flexible materials, the time, temperature and pressure for injecting the materials were followed as per the manufacturer’s instructions. Total 20 samples for control (Trevelon denture base materials) were prepared by compression moulded process, for each test. ANOVA test was applied to calculate p value. Unpaired t test was applied to calculate t-value. Tukey–Kramer multiple test was provided for comparison between the groups for flexural and impact strength. From the statistical analysis, it was found that, the impact strength of Group III (Valplast) was found to be the highest than all other groups and nearer to the control group. Whereas Group IV (Bre-flex) had the maximum flexural strength. The flexural strength of Group I (De-flex) was lowest than all other groups and nearer to control group. The values were found to be statistically significant but clinically non-significant with the control (p < 0.001). The overall results of the study showed that, Group III (Valplast) had the maximum impact strength and Group I (De-flex) had the lowest flexural strength, whereas Group IV (Bre-flex) had the maximum flexural strength and lowest impact strength.
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References
Meng Thomas R et al (2005) Physical properties of four acrylic denture base resins. J Contemp Dent Pract 6(4):1–5
Negrutiu Meda et al (2005) Thermoplastic resins for flexible framework removable partial dentures. TMJ 55:3
Phillips′ Science of Dental materials. 11th edn. 143–170
Craig′s restorative Dental materials. 12th edn. 21–37
Ali parvizi et al. (2004) Comparison of the dimensional accuracy of injection moulded denture base materials to that of conventional pressure-pack acrylic resin. J Prosthodont 13:83–89
Anderson GC et al (1988) Dimensional stability of injection and conventional processing of denture baseacrylic resin. J Prosthet Dent 60:3
Kausch HH (1987) Polymer fracture. 2nd edn. Springer, Berlin
Yee A (1987) Impact resistance. In: Mark HF (ed) Encyclopedia of polymer science and technology. Vol 8. 2nd edn. Wiley, New York p 36–68
Memon MS et al (2001) Some mechanical properties of highly cross linked, microwave-polymerized, injection moulded denture base polymer. Int J Prosthodont 14:214–218
Karacaer O et al (2003) The effect of length and concentration of glass fibers on the mechanical properties of an injection and compression moulded denture base polymer. J Prosthet Dent 90:385–393
Lowe LG (2004) Flexible denture flanges for patients exhibiting undercut tuberosities and reduced width of the buccal vestibule: a clinical report. J Prosthet Dent 92:128–131
Meijer GJ (2007) Provisional flexible denture to assist in undisturbed healing of the reconstructed maxilla. J Prosthet Dent 98:327–328
Dhiman CRK (2009) Midline fractures in single maxillary complete acrylic verses flexible dentures. MJAFI 65:141–145
Takabayashi Y (2010) Characteristics of denture thermoplastic resins for non-metal clasp dentures. Dent Mater J 29(4):353–361
Ruyter E et al (1980) Flexural properties of denture base polymers. J Prosthet Dent 43:1
Johnston EP et al (1981) Flexure fatigue of ten commonly used denture base resins. J Prosthet Dent 46:5
Deboer J et al (1984) The effect of carbon fiber orientation on the fatigue resistance and bending properties of two denture resins. J Prosthet Dent 51:1
Donovan TE (1985) Physical properties of acrylic resins polymerized by four different techniques. J Prosthet Dent 54:4
Success injection systemand Lucitone FRS flexible dental resin. (Technique high light sheet : partial dentures):Article from internet
Dixon DL (1992) The transverse strengths of three denture base resins reinforced polyethylene fibers. J Prosthet Dent 67:417–419
Williamson DL et al (1994) Effect of polyethylene fiber reinforcement on the strength of denture base resins polymerized by microwave energy. J Prosthee Dent 72:635–638
John J et al (2001) Flexural strength of heat polymerized polymethyl methacrylate denture reinforced with glass, aramid or nylon. J Prosthet Dent 86:424–427
Silva FAP et al (2002) Effect of intrinsic pigmentation on the flexural strength of a microwave cured acrylic resins. Braz Dent J 13(3):205–207
Pfeiffer P et al (2005) Flexural strength and moduli of hypoallergenic denture base materials. J Prosthet Dent 93:372–377
Golbidi F et al (2007) An evaluation of the flexural strength properties of maliodent and acropars heat polymerized acrylic resins. J Dent 4(2):68–71
Diaz-Arnold AM et al (2008) Flexural and fatigue strengths of denture base resin. J Prosthet Dent 100:47–51
Price CA (1986) The effect of cross linking agents on the impact resistance of a linear poly (methyl-methacrylate) denture-base polymer. J Dent Res 65(7):987–992
Ting-Way Y (1991) The effects of hollow microsphere fillers on density and impact strength of denture base resin. J Prosthet Dent 65:147–152
Gianluca Z (2003) comparison of fracture test of denture base materials. J Prosthet Dent 90:578–585
Sung-hunkim (2004) The effect of reinforcement with woven E-glass fibers on the impact strength of Complete denturesfabricated with high impact acrylic resins. J Prosthet Dent 91:274–280
Faot F (2006) Impact strength and fracture morphology of denture acrylic resins. J Prosthet Dent 96:367–373
Faot F (2008) Fractographic analysis, accuracy of fit and impact strength of acrylic resins. Braz Oral Res 22(4):334–339
Gulay U (1999) Effect of five woven fiber reinforcement on the impact and transverse strength of denture base resins. J Prosthet Dent 81:616–620
Kanie T (2000) Flexural properties and impact strength of denture base polymer reinforced with woven glass fibers. Dent Mater 16:150–158
Shamnur SN (2010) “Flexible dentures”—an alternate for rigid dentures? J Dent Sci Res 1:74–79
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Abhay, P.N., Karishma, S. Comparative Evaluation of Impact and Flexural Strength of Four Commercially Available Flexible Denture Base Materials: An In Vitro Study. J Indian Prosthodont Soc 13, 499–508 (2013). https://doi.org/10.1007/s13191-012-0203-0
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DOI: https://doi.org/10.1007/s13191-012-0203-0