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

Graetz, Christian; Düffert, Paulina; Heidenreich, Ralf; Seidel, Miriam; Dörfer, Christof E.

OBJECTIVE/AIM: To identify small particle concentrations (eight categories: ≤0.1 µm × ≤5.0 µm) 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) °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 ΔPN (ΔPN = [post-PN] − [pre-PN]). RESULTS: Mean ΔPN (SD) ranged between −8.65E+06 (2.86E+07) counts/m(3) for 0.15 µm and 6.41E+04 (2.77E+05) counts/m(3) for 1.0 µm 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 ΔPN was detected for smaller particles by high-speed tooth preparation (0.1–0.3 µm; 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 ΔPN 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.