Effectiveness of Microwave Sterilization on Surface Roughness of Polyvinyl Siloxane Impression Material

Abstract

Aims: The study aimed to investigate the effect of sterilization by microwave irradiation at 640W on the surface roughness of polyvinyl siloxane. Materials and methods: 30 samples of addition silicone impression material with a thickness of 20mm and 3mm as diameter. The acrylic mold was used for the samples' fabrication. The samples were divided into six groups each group had five specimens (C) control (3MWD) Samples irradiated for 3minute in dry conditions, (6MWD) samples irradiated for 6minute in dry conditions, (3MWW) samples irradiated for 3minute in wet condition, (6MWW) samples irradiated for 6minute in wet condition and (CHX) samples immersed in chlorhexidine with 0.5% concentration for one hour. A profilometer (Talysurf 10, R.P.I. LTD, Metrology Division) is used for measuring surface roughness by taking the means of three points with the aid of a stylus. Results: There were statistical differences between the control group and the tested groups. Mann-Whitney showed that only 3MWD had no statistical differences from the control group. Conclusions: Disinfection of polyvinyl siloxane using the microwave at 640W for 3 minutes is safe or recommended regarding its least effect on the surface roughness.

Keywords

• polyvinyl siloxane
• microwave irradiation
• surface roughness