The efficacy of an extraoral scavenging device on reducing aerosol particles ≤ 5 μm during dental aerosol-generating procedures: an exploratory pilot study in a university setting

Objective/aim To identify small particle concentrations (eight categories: <= 0.1 mu m x <= 5.0 mu m) induced by aerosol-generating procedures (AGPs; high-speed tooth preparation, ultrasonic scaling; air polishing) under high-flow suction with a 16-mm intraoral cannula with and without an additional mobile extraoral scavenger (EOS) device during student training. Materials and methods Twenty tests were performed (16.94 m(2) room without ventilation with constant temperature (26.7 (1.1) degrees C and humidity (56.53 (4.20)%)). Data were collected 2 min before, 2 min during, and 6 min after AGPs. The EOS device and the air sampler for particle counting were placed 0.35 m from the open mouth of a manikin head. The particle number concentration (PN, counts/m3) was measured to calculate Delta PN (Delta PN = [post-PN] - [pre-PN]). Results Mean Delta PN (SD) ranged between -8.65E+06 (2.86E+07) counts/m(3) for 0.15 mu m and 6.41E+04 (2.77E+05) counts/m(3) for 1.0 mu m particles. No significant differences were found among the AGP groups (p > 0.05) or between the AGP and control groups (p > 0.05). With an EOS device, lower Delta PN was detected for smaller particles by high-speed tooth preparation (0.1-0.3 mu m; p < 0.001). Discussion A greater reduction in the number of smaller particles generated by the EOS device was found for high-speed tooth preparation. Low Delta PN by all AGPs demonstrated the efficacy of high-flow suction. Conclusions The additional use of an EOS device should be carefully considered when performing treatments, such as high-speed tooth preparation, that generate particularly small particles when more people are present and all other protective options have been exhausted.