Discussion
forceful
In the wake of the COVID-19 pandemic that resulted with forceful closure of dental practices due to cross-contamination concerns, we aimed to reassess the disinfection efficacy of common non-sterilizable dental materials. These items, widely exchanged in dental settings, pose a significant cross-contamination risk among patients, dentists, and lab technicians. Our study included indelible pencils, chosen for their permanence in marking dentures and labeling impressions. Despite their single-use nature, some clinics reuse them, warranting attention to this issue.Our results demonstrate that the UV irradiation group (UVG) achieved a marked and consistent complete eradication of UV light disinfection is highly effective against diverse microorganisms, safe, and cost-effective, reducing aerosol spread compared to chemicals. Handheld UV wands work well but may harm eyes without proper distance controlEffectiveness of the UV disinfection unit is dependent on multiple parameters, including the UV radiation wavelength and intensity, the design of the UV chamber, the distance between the UV machine's bulb and the specimen, and the time of exposure to the radiation. Based on wavelength, there are three types of UV rays: UV-A (320–400 nm), UV-B (280–320 nm), and UV-C (100–280 nm). UV-C radiation has the most bactericidal effect and was chosen in our studyThe importance of light intensity is well established. Previous research showed that UV exposure of 24 Watt (3750 μW/cmDirect access of the disinfectant to microorganisms is essential to ensure disinfection of all surfaces. Lualdi et al.The UV exposure times vary significantly in the literature, ranging from 30 s to 20 min for various materials and under different lamp intensities and exposure conditionsThe required sample size was estimated based on the desired effect size. The aim of this study was to establish if the UV method has a significantly better antibacterial effect than current practice (spraying) to the extent that would warrant change in practice. An 80% reduction in the CFU would be considered a sufficiently large effect size. The required sample size was calculated using G*Power to achieve a power of 95% for one-way ANOVA between three groups of equal allocation (i.e., UV, Spray, and Control) and an effect size of 80%. The calculation identified that a sample size of 9 (3 in each group) would achieve a power of 99.6%.Since our study would be able to statistically detect the required “clinically significant” effect size with a sample of nine at a sufficient at a “high” power, increasing the sample size to detect a smaller and “statistically significant but non-clinically significant” difference would be counterproductive. However, in order to ensure reproducibility and independence of observations, we obtained three technical replicates for each experiment, and repeated the experiment on three different days to achieve biological replicates.The negative control group confirmed the necessity of using disinfectants. This aligns with Rossi’s findingsIn conclusion, our study highlights the differing effectiveness of UV irradiation and spray treatment in eliminating microbes from various materials, with statistically significant differences confirmed through effect size and power analyses. While UV irradiation effectively eradicated microbes in our study, it is advisable to pre-clean dental materials to ensure optimal UVC light penetration. Future research should explore additional materials, pathogenic microbes, and compare to standardized sodium hypochlorite immersion for further validation