RESUMO
Background/purpose: Asymptomatic COVID-19 patients visit the dental clinic for routine treatment, during which, high-speed handpieces, and third-use sprayers can produce aerosols. We focused on the effect and possible inadequacy of personal protective equipment (PPE) while cleaning teeth and assessed whether doctors' proficiency was related to the range of spraying droplets. Materials and methods: Doctors were divided into three different groups: attending physicians, residents, and intern respectively. Each doctor treated 15 patients; each group comprised 30 patients. The dentists wore leg covers, shoe covers, medical masks, haircaps, full masks, waterproof barrier gowns, and gloves. Each patient was covered with a waterproof hole towel, and the upper edge was fixed to the patient's nose with a medical tape. After cleaning the teeth with water contained red pigment, the spattering distance and range of droplets were calculated. Concurrently, we examined whether there was any droplet contamination on the PPE. Results: With the exception of shoe covers, haircaps, and medical surgical masks, pigment splash marks were found on both the dentist and assistant's PPE. The interns performed cleaning for a significantly longer time than the residents and attending physicians, with a significant statistical difference (P < 0.05). The spatter distance for the interns was significantly larger than the residents (P < 0.05). Conclusion: It is recommended that the hole towel be centered on the patient's nose tip, at least larger than a radius of 54.9-64.5 cm. The dentist's proficiency did cause differences in the duration of teeth cleaning, which further affects the spatter distance.