Aplicação de Dispositivo de Radiação UV-C como Tecnologia Complementar no Controle Microbiológico em Ambientes de saúde

Abstract

This dissertation investigated the effectiveness of a low-power ultraviolet-C (UV-C) radiation device as an auxiliary technology for biological control of surfaces in dental environments. The research consisted of two complementary studies: a scoping review and an experimental study. The scoping review aimed to map the available evidence on the germicidal effectiveness of UV-C radiation against bacterial and fungal microorganisms on clinical surfaces and dental-medical instruments. A total of 31 studies with varying physical parameters (dose, exposure time, and distance) were included, revealing that germicidal effectiveness strongly depends on the interaction between these factors, as well as the geometry and material of the treated surfaces. The experimental study evaluated the spectral characterization, dose distribution, and microbiological effectiveness of a low-power UV-C device developed for dental offices. Radiation intensity was monitored using colorimetric dosimeters distributed across various points of a standard dental clinic. Germicidal effectiveness was assessed on seven commonly contaminated clinical surfaces using selective mannitol agar for Staphylococcus aureus and S. epidermidis. Exposure to the device for five minutes significantly reduced bacterial colonies (>90%) on surfaces that received doses between 25–35 mJ/cm². An exponential relationship was observed between dose, distance from the source, and germicidal effectiveness. Distant or shaded surfaces showed lower microbial reduction, while nearby and reflective surfaces demonstrated better results. The findings indicate that the complementary use of UV-C radiation can enhance biosafety in dental environments, provided there is adequate planning of the device’s positioning and exposure time. The evaluated device proved effective even on surfaces that are difficult to disinfect manually, such as the dental chair. The proposal of a portable, low-power system contributes to a sustainable, safe, and accessible approach to infection control. Therefore, the results reinforce the translational potential of UV-C radiation as a complementary technology to conventional cleaning and disinfection practices in Dentistry.