Infection Prevention and Control Practices of Dental Hygienists in the United States During the COVID-19 Pandemic: A longitudinal study

Purpose: The SARS-CoV-2 virus continues to mutate, and the COVID-19 pandemic remains a global health crisis. The purpose of this longitudinal study was to continue to analyze the use of infection prevention and control practices (IPC) and personal protective equipment (PPE) by dental hygienists in the United States (US) during the COVID-19 pandemic. Methods: Web-based surveys on COVID-19 related health, IPC, and PPE were administered monthly to a panel of US licensed dental hygienists (n=6,976) from September 2020 to August 2021. Trends over time and predictors of IPC and PPE use were estimated using Stata 17.0 xt commands and multilevel multivariable logistic regression. Linear regression modeling for trends in time and tests for changes in trends were conducted (Joinpoint Regression Program, Version 4.9.0.0). Results: Almost all practicing dental hygienists (99.9%, 14,926 observations) reported COVID-19 specific IPC in place at their primary dental practice. Consistently >96% of dental hygienists reported operatory disinfection and staff masking over the study period. Patient face masking and physical protections such as barriers or air filtration increased in use over time, then declined in spring 2021. Screening or interviewing patients before appointments, checking patient temperatures before treatment, checking staff temperatures at shift start, disinfecting frequently touched surfaces, and encouraging distance between patients were reported by >85% of respondents until March 2021, at which point significant decreases were observed. Wearing a mask or respirator and eye protection during patient care consistently rose over time from September 2020 (77.1%) to August 2021 (81.4%). Always wearing a N95 or equivalently protective respirators during aerosol generating procedures peaked in 2/2021 and declined thereafter. Dental practice setting, supply of respirators, COVID-19 vaccination, and COVID-19 community transmission level were significantly associated with IPC and PPE use. Conclusion: Most US dental hygienists reported always wearing masks and eye protection during patient care and a variety of IPC types have been instituted to reduce the risk of COVID-19 transmission in dental practice settings. However, the use of N95 or equivalent respirators and some additional IPC methods declined during 2021.