Evaluation of the Droplets and Aerosols, Posing Potential Risks of COVID-19 Disease Infection Transmission in Dentistry: A Systematic Review and Meta-Analysis of Observational Studies

Objective: To evaluate the droplets and aerosols, posing potential risks of infection transmission of COVID-19 disease in dentistry. Material and Methods: PubMed, Embase, ISI, Scopus, Medicine have been used to search for articles between September 2019 to December 2020. Data extracted from the studies were included, study, study design, sample size, Sample collection time, Hallway Air Samples (copies/L of air), Personal Air Samples (copies/L of air). Effect size with 95% confidence interval (CI), fixed effect model, Inverse-variance methods were calculated. The Meta-analysis was evaluated with Stata/MP v.16 statistical software (The fastest version of Stata). Results: According to the purpose of the study, 64 articles were found; studies that did not meet the inclusion criteria were excluded from the study; the full text of 11 studies was reviewed. Finally, two studies were selected. The effect size of airborne COVID-19 concentrations of the hallway and personal air samples was 64% copies/L of air (ES, 0.64 95% CI=-1.45-2.73) and 100% copies/L air (ES, 1.00 95% CI=-1.77-3.76), respectively. Conclusion: Evidence of aerosol transmission of COVID-19 in observational studies of patients with COVID-19 was 64% copies/L of air and 100% copies/L of air in the hallway and personal air samples, respectively.