Efficacy of UVC Radiation in Reducing Bacterial Load on Dental Office Surfaces

Background/Objectives: Environmental contamination of dental surfaces is a signifi-cant source of cross-infection. Ultraviolet-C (UVC) irradiation offers rapid, resi-due-free decontamination, but quantitative data for dental surfaces are limited. We aimed to evaluate the germicidal efficacy of UVC on three high-touch surfaces: a wooden work table, a stainless-steel consumables table, and a dental unit table. Meth-ods: Surfaces were sampled at baseline, after 5 min (27 mJ/cm²), and after 10 min (54 mJ/cm²) of UVC exposure at 90 µW/cm². Colony-forming units (CFU/cm²) were enu-merated using Mueller–Hinton agar. Results: Baseline contamination exceeded 200 CFU/cm², predominantly Staphylococcus spp. A 5-minute exposure reduced counts by >99%, and a 10-minute exposure eradicated vegetative bacteria, with a single Ba-cillus colony detected. Material properties (porosity, reflectivity, and grooves), along with quantified parameters like surface roughness (Ra) and contact angle, influenced minor differences in decontamination. Conclusions: Used with appropriate safety protocols, short-duration UVC irradiation effectively decontaminates dental surfaces and can complement chemical disinfection. To accurately assess UVC efficacy under realistic clinical conditions, future studies must incorporate artificially soiled surfaces, biofilms, and emerging far-UVC/UV-LED technologies.