Background and Aim: Shade guide discoloration after disinfection can interfere with the appropriate color selection for dental restorations. Since one of the most important issues for patients is the color of the final restoration, the discoloration of shade guides due to DISINFECTANTs will be important. Infection control is a definite and important matter in dentistry. Due to the contradictory results of studies on the effect of DISINFECTANTs on shade guide discoloration, this study aimed to examine the discoloration of the Vita classical shade guide by glutaraldehyde DISINFECTANT. Materials and Methods: In this experimental study, samples of A4, B4, C4, and D4 colors were selected from the Vitapan classical shade guide, 10 pieces each (40 samples in total). Three samples of each color were immersed in distilled water as a control while the other seven were immersed in a 2% glutaraldehyde DISINFECTANT solution. The shade pilot spectrophotometer was used for colorimetry, which was performed at baseline and 24, 48, and 72 hours after the immersion. The color of the samples was evaluated based on the CIE Lab system. The data were analyzed with two-way analysis of variance (ANOVA) and Tukey’, s test. Result: The rate of color change (Δ, E) of the samples was higher in the glutaraldehyde group than in distilled water (P<0. 05). In addition, color change in both groups showed a significant difference at different times (P<0. 05). Conclusion: The Vitapan classical color samples discolor by immersion in 2% glutaraldehyde DISINFECTANT after 24, 48, and 72 hours, but this color change is not clinically detectable (Δ, E<1).

Background and Objectives: Based on previous studies it was known that in the most of countries prevalence of nosocomial infections is 6 to 10 percent. However with using right methods of disinfection and antiseptics and sanitation a lot of this infections could be controlled with a low cost. Various mineral and organic antiseptics could be used in hospitals to disinfect. The objective of this study is to possibility of making a liquid DISINFECTANT in method of NaCl electrolysis and study it's application for disinfection of surfaces.Materials and Methods: A pilot was designed for this study. Solutions with 5 density of NaCl (1, 3, 5, 7, 10 %) in 4 different pH (2, 4.5, 7, 9.5, 10) was prepared and got under influence of 5 currents (0.2, 0.4, 0.6, 0.8, 1 Ampers).Then a sample gathered from anode column of pilot and was examined on Staphilococus aureus microbial strain based on 9485 standard of ISIRI.Results: Results from this study showed that increasing density of salt, increasing electrical flow and decreasing pH causes more bacterial mortality in Staphilococus aureus strain.Conclusion: Results from this study showed that in1- 5% salt density, pH=7 and 1A electrical flow every bacteria in Staphilococus aureus strain will be destroyed completely.

Introduction: This study aims to evaluate surface wettability of additional silicone impression materials, which are immersed in different disinfecting agents with different time intervals. Methods: Ninety disk-shaped specimens to be eighteen specimens from each of five different impression materials (four vinyl polysiloxane and one vinyl polyether siloxane) were prepared. The specimens were divided into six groups according to the disinfecting agents (one of them containing ethanol and other one containing benzalkonium chloride) and periods. Then, the specimens were immersed in two disinfecting agents for 1 minute, 1 hour and 24 hours. Later, surface wettability was tested and recorded. Data were analyzed with analysis of variance (ANOVA). Results: There was no difference between impression materials and DISINFECTANTs in terms of the effect on the contact angle (p>0. 05), and there was a significant difference between disinfection times (p=0. 001). Conclusions: One-minute disinfection process increases wettability of specimens compared to long term disinfections.

Background: To achive natural and harmonic restoration color, shade matching is a commonly used method in dental practice using shade guides. To prevent infection, shades guides are required to be disinfected. Using of disinfection solutions gradually affect the color of dental equipment. The aim of this study was to evaluate the effect of three DISINFECTANTs sodium hypochlorite solution 5.25%, Deconex and Glutar aldeid 2% on the color stability vita Lumin shade guide by using the spectrophotometer.Methods: Samples were divide into 4 groups (n=10) one of them as a control group, was excluded. In order to simulate the condition of immersion per one year, they were immersed for 24 hours in DISINFECTANT and for 5 minutes, rinsed with distilled water in ultra-sonic machines and washed under the tap water for 30 seconds.Using the spectrophotometer based on CIELab color system, statistical analysis were done using done by one way ANOVA and Dunnett C test.Results: There were significant differences in L (P<0.001) and b (p<0.01) values in all groups as compared to those of control group. In a value there were no significant differences in all of the groups for  DE (p>0.05).Conclusion: If we could follow the manufacturer’s recommendations about time and how to use DISINFECTANTs, it would prevent clinically perceptible changes in shade guides color.

Background: Mouthguard (MG) DISINFECTANT sprays are available for maintaining MG hygiene. The effect of these sprays against Streptococcus sobrinus is still unknown. The purpose of this study was to evaluate the antibacterial effect of an MG DISINFECTANT spray against S. sobrinus using the modified Received: 28-May-2020 Revised: 07-Aug-2020 Accepted: 10-Sep-2020 Published: 19-Jul-2021 ISO 22196 standard. Materials and Methods: In this in vitro study, we used the following treatment groups for antibacterial testing: MG spray-1 (left in spray for 30 s), MG spray-2 (60 s), and control (n = 4). All analyses were performed at a statistically significant level (P = 0. 05) using JMP ® 14. Results: The log colony-forming units of the MG spray-2 group were significantly lower than those of the other groups. The antibacterial activity of MG spray-2 against S. sobrinus was >2. 1. Conclusion: We confirmed the antibacterial effect of the MG spray against S. sobrinus, and it was influenced by the treatment duration, with the optimum effect at a longer duration.