Factors Modulating Fallow Period of Aerosol-Generating Dental Procedures in a Clinical Setting

Area of Science:

• Dental hygiene
• Infectious disease control
• Respiratory aerosol science

Background:

• COVID-19 pandemic necessitated revised dental practice guidelines to prevent SARS-CoV-2 transmission.
• Aerosol-Generating Procedures (AGPs) in dentistry pose a risk, leading to recommendations for fallow periods and enhanced personal protective equipment (PPE).
• The efficacy of ventilation and increased chairside assistance in mitigating aerosols during dental procedures requires further investigation.

Purpose of the Study:

• To evaluate the impact of enhanced ventilation (20 additional air changes per hour [ACH]) and four-handed dentistry on aerosol reduction during supportive periodontal therapy (SPT).
• To determine if additional air changes per hour or the presence of an assistant significantly reduces aerosol persistence post-procedure.
• To assess the necessity of extended fallow periods following AGPs in dental settings.

Main Methods:

• A study involving 34 patients undergoing SPT utilizing air polishing, ultrasonic, and hand instrumentation.
• Procedures were conducted in a closed operatory with either 0 or 20 additional ACH, with either 2-handed or 4-handed dentistry.
• Aerosol levels were monitored to assess return to baseline following the AGP.

Main Results:

• 20 additional ACH were found to be sufficient to eliminate aerosols generated during SPT before the AGP concluded.
• The presence of a dental assistant (four-handed dentistry) did not significantly alter the time for aerosol particles to return to baseline.
• No significant difference was observed in aerosol clearance times between 2-handed and 4-handed dentistry.

Conclusions:

• Enhanced ventilation (20 additional ACH) is effective in managing aerosols during AGPs in dental settings.
• Extended fallow periods are not supported by this study's findings when adequate ventilation is present.
• Four-handed dentistry does not offer significant additional benefit in aerosol reduction compared to 2-handed dentistry with sufficient ventilation.