Mechanical Properties of Elastomeric Impression Materials: An In Vitro Comparison

Abstract

Purpose. Although new elastomeric impression materials have been introduced into the market, there are still insufficient data about their mechanical features. The tensile properties of 17 hydrophilic impression materials with different consistencies were compared. Materials and Methods. 12 vinylpolysiloxane, 2 polyether, and 3 hybrid vinylpolyether silicone-based impression materials were tested. For each material, 10 dumbbell-shaped specimens were fabricated (n = 10), according to the ISO 37:2005 specifications, and loaded in tension until failure. Mean values for tensile strength, yield strength, strain at break, and strain at yield point were calculated. Data were statistically analyzed using one-way ANOVA and Tukey's tests (α = 0.05). Results. Vinylpolysiloxanes consistently showed higher tensile strength values than polyethers. Heavy-body materials showed higher tensile strength than the light bodies from the same manufacturer. Among the light bodies, the highest yield strength was achieved by the hybrid vinylpolyether silicone (2.70 MPa). Polyethers showed the lowest tensile (1.44 MPa) and yield (0.94 MPa) strengths, regardless of the viscosity. Conclusion. The choice of an impression material should be based on the specific physical behavior of the elastomer. The light-body vinylpolyether silicone showed high tensile strength, yield strength, and adequate strain at yield/brake; those features might help to reduce tearing phenomena in the thin interproximal and crevicular areas.

Penetration of Different Impression Materials into Exposed Dentinal Tubules during the Impression Procedure

“…The alternative hypothesis demonstrated that the presence of the tags was statistically significant in the samples under examination, and therefore relevant from the clinical point of view. It is now known that the interface area between the impression material and the tooth is the most complex to manage due to the potential for elastic deformation during removal [38]. For this reason, the characteristics of the elastic deformation during the phase of removal of the impression are among the most studied rheological characteristics of impression materials [39,40].…”

Simple and novel technique for fabrication of prosthetic vaginal dilators

“…Addition silicones also have additional properties, such as very high elastic recovery and high tear and tensile strengths 11. The laboratory study by Re et al has proven that addition silicones have shown higher in vitro results for tensile strength at break and yield strength 12. Hence, with the support of the ideal mechanical properties of addition silicones, the authors have used only the addition silicone material for the construction of the vaginal dilator to maintain the adequate patency of the neovagina in the present case report.…”

Empirical study of alginate impression materials by customized proportioning system

“…Then, the mould was opened, and the test specimens were removed from the mould. Re et al5 indicated that there were significant effects of the waiting period on both viscosity and mechanical properties of the alginate impression materials. Therefore, all tests were conducted after enough setting times.…”

“…While alginate impression materials indicate high mechanical properties to ensure their stability during dental treatments,5 alginate impression materials are required to have enough viscosity to make a way into all oral structures. There are various mechanical tests applied to impression materials and their mechanical properties, such as ANSI/ADA specification no.…”