Effects of Various Disinfection Methods on the Material Properties of Silicone Dental Impressions of Different Types and Viscosities

Abstract

There is an ongoing search for novel disinfection techniques that are not only effective, cheap, and convenient, but that also do not have adverse effects on the properties of dental impressions. We compared the effects of various methods (UVC, gaseous ozone, commercial solution, and spray) on the dimensional change, tensile strength, and hardness of silicone impressions. Moreover, as a secondary aim, we performed a statistical comparison of the properties of nondisinfected addition (Panasil Putty Soft, Panasil monophase Medium, Panasil initial contact Light) and condensation silicones (Zetaplus Putty and Oranwash L), as well as a comparison of materials of various viscosities (putty, medium-bodied, and light-bodied). Our results revealed that addition silicones had higher dimensional stability, tensile strength, and Shore A hardness compared to condensation silicones. Both traditional (immersion and spraying) and alternative methods of disinfection (UVC and ozone) had no significant impact on the tensile properties and dimensional stability of the studied silicones; however, they significantly affected the hardness, particularly of Oranwash L. Our study demonstrated that, similarly to standard liquid disinfectants, both UVC and ozone do not strongly affect the material properties of most silicones. However, before recommendation, their usefulness for each individual material should be thoroughly evaluated.

Keywords: UVC; dental materials; dimensional stability; hardness; ozone; tensile strength.

Figure 1

Linear dimensional change in C-silicones (Zetaplus Putty and Oranwash L) after disinfection using various methods; ** p < 0.01 for the comparison between the study (disinfected) groups and the control (nondisinfected) group.

Figure 2

Linear dimensional change in A-silicones (Panasil Putty Soft, Panasil monophase Medium, and Panasil initial contact Light) after disinfection using various methods.

Figure 3

Tensile strength of C-silicones (Zetaplus Putty and Oranwash L) after disinfection using various methods.

Figure 4

Tensile strength of A-silicones (Panasil Putty Soft, Panasil monophase Medium, and Panasil initial contact Light) after disinfection using various methods.

Figure 5

Shore A hardness of C-silicones (Zetaplus Putty and Oranwash L) after disinfection using various methods; * p < 0.05 and **** p < 0.0001 for the comparison between the study (disinfected) groups and the control (nondisinfected) group.

Figure 6

Shore A hardness of A-silicones (Panasil Putty Soft, Panasil monophase Medium, and Panasil initial contact Light) after disinfection using various methods; * p < 0.05, ** p < 0.01, and **** p < 0.0001 for the comparison between the study (disinfected) groups and the control (nondisinfected) group.

Figure 7

Study design with a schematic representation of (a) the test block used for the measurement of dimensional change in accordance with the ISO 4823:2015 standard and (b) the dumbbell-shaped test specimen used for the measurement of tensile strength in accordance with the ISO 37:2017(E) standard.