Aerosols in Dentistry Amid Sars-COV-2

Dr. Dana Graves

Dr. David Hershkowitz The SARS-CoV-2 pandemic has caused a considerable amount of apprehension in dental practitioners and patients alike. Since dental procedures generate aerosols, increased infection risk is at the forefront of dentist’s concerns.

Dr. Dana Graves, Professor of Periodontics and Vice Dean for Research & Scholarship, and Dr. David Hershkowitz, Division Chief of Restorative Dentistry led a study aimed to establish risk of Covid-19 in a dental setting in which aerosols are generated. Through the prospective observational study, they wanted to determine if a dental office was a safe environment when proper PPE was implemented. Faculty, staff, and students who practiced dentistry only at PDM, had 10 or more hours of direct patient exposure, and had no confirmed past Covid-19 infections were qualified for the study. Enrolled participants completed study visits once every two months at which time venous blood was drawn for serologic analysis to detect the presence of antibodies to SARSCoV-2. Launched in partnership with the Perelman School of Medicine, the study began in September 2020 and terminated early in January 2021 due to the emergence of vaccines. There was a high level of collaboration throughout the process. The Center for Clinical and Translational Research spearheaded the study with the help of Dr. Joseph Fiorellini, Professor of Periodontics, who assembled a team of residents who were trained to perform the blood collection as per the research protocol. The Dean’s office was instrumental in providing funding, and Dr. Jordan-Sciutto’s lab prepared the blood samples. Dr. Scott Hensley’s lab at the Dept of Microbiology, PSOM was in charge of the antibody analysis. “I thought it was an extraordinarily high level of cooperation. We couldn’t have pulled this off without the contribution of everyone involved. And that includes subjects who volunteered, the Clinical Research Center, including Pat Corby, Kira Nightingale, Rosa Urbina, and the team of research assistants and residents who contributed to the overall study conduct. Although we believed the study was an important step in assessing PDM practices to prevent spread of Covid-19 during patient contact, this would never have gotten off the ground if it were not for the team.” —Dr. Graves

The study found that the infection rate at PDM was 5.5%, and that all of the positive antibody cases were traced to exposure outside of PDM. Therefore, infectious risk outside

of PDM was much higher than inside PDM treating patients. In addition, the PPE guidelines and practices were proven to be effective in our study. The study also found that working as a student or faculty in one clinic or another did not significantly affect the infection rate of SARS-CoV-2. Symptomatic subjects had a higher infection rate than asymptomatic subjects, which stresses the importance of daily screening questions as a necessary component of transmission control. Overall, the guidelines implemented by PDM were very effective in minimizing risk. “We cannot take shortcuts on PPE. PPE, just like during the HIV epidemic, is the key to preventing transmission.” —Hershkowitz Knowing what we know now, the dental field will be better equipped in addressing respiratory virus outbreaks. The two main issues that led the CDC to mandate closure of dental clinics was the 1) lack of knowledge of how the virus was transmitted and 2) concerns about PPE effectiveness and supplies. The implications of this study support that the ramp up of patient treatment is acceptable if appropriate PPE practices are followed. This information is valuable in keeping dental practices open. There is no doubt that research was paramount in mitigating the pandemic. From discovering the modes of transmission to developing a vaccine, science has never been more relevant to the public than today. In the past, we have seen a similar urgency placed on research during the AIDS epidemic as so much was unknown about the virus.

Science has advanced tremendously, in the past few decades, allowing researchers to act quickly, generate results, and develop therapies and protocols in response to a contagion. Interestingly, politics have played a more considerable role in the perception of science and healthcare through conflicting media outlets that makes universal safe practices more difficult to implement. “The trust that the layperson has in the scientific community has diminished because of media and politics and so forth, leaving the layperson asking, ‘Are they telling me the truth?’” —Hershkowitz Although science has progressed significantly, there have been several obstacles that stand in the way of implementing knowledge. “In some ways you can look at this and say science has advanced, but society has not in dealing with public health issues during a pandemic.” —Graves.

Thus, the way we critically evaluate news, how we educate our patients, and reassure them of their safety is of utmost importance. This study has illustrated the tremendous value that collaboration holds in research as well as the significance that clinical research has on our everyday lives. Founded two years ago, The Center for Clinical and Translational Research has become an integral resource to clinical researchers at PDM as they provide services that span the full spectrum of a study, from conceptualization to closeout, for industry, federal, and foundation sponsors. Madelaine Li, one of the first students in the Clinical and Translational Research Honors program, played an active role in the study and won the Student Competition for Advancing Dental Research and its Application (SCADA) Award this year. Her experience at the Center for Clinical and Translational Research has supported her growth in becoming a confident and independent team member who can conduct study visits in a well-calibrated manner. She further promoted students’ involvement in the center saying, “This journey is truly the highlight of my life in dental school and my career in the future.” For students interested in the Center for Clinical and Translational Research, please visit: www.dental.upenn.edu/research/center-forclinical-and-translational-research/

There is no doubt that research was paramount in mitigating the pandemic. From discovering the modes of transmission to developing a vaccine, science has never been more relevant to the public than today.