Graetz Christian, Sayk Naomi, Düffert Paulina, Heidenreich Ralf, Dörfer Christof E, Cyris Miriam
Clinic for Conservative Dentistry and Periodontology, University Hospital Schleswig-Holstein, Campus Kiel, Arnold-Heller-Str. 3, Haus B, Kiel 24105, Germany.
Institute of Air Handling and Refrigeration, Bertolt-Brecht-Allee 20, Dresden 01309, Germany.
Int J Dent. 2022 Jun 24;2022:9973623. doi: 10.1155/2022/9973623. eCollection 2022.
The study aimed to analyze different ways to control air quality during/after aerosol-generating procedures (AGPs) in a small skills lab with restricted natural air ventilation in preclinical dental training (worst-case scenario for aerogen infection control). Different phases were investigated (AGP1: intraoral high-volume evacuation (HVE); AGP2: HVE plus an extraoral mobile scavenger (EOS)) and afterward (non-AGP1: air conditioning system (AC), non-AGP2: AC plus opened door).
Continuous data collection was performed for PM1, PM2.5, and PM10 (µg/m), CO2 concentration (ppm), temperature (K), and humidity (h) during two summer days (AGP: = 30; non-AGP: = 30). While simulating our teaching routine, no base level for air parameters was defined. Therefore, the change in each parameter (Δ = [post]-[pre] per hour) was calculated.
We found significant differences in ΔPM2.5 and ΔPM1 values (median (25/75th percentiles)) comparing AGP2 versus AGP1 (ΔPM2.5: 1.6(0/4.9)/-3.5(-10.0/-1.1), =0.003; ΔPM1: 1.6(0.6/2.2)/-2.2(-9.3/-0.5), =0.001). Between both non-AGPs, there were no significant differences in all the parameters that were measured. ΔCO increased in all AGP phases (AGP1/AGP2: 979.0(625.7/1126.9)/549.9(4.0/788.8)), while during non-AGP phases, values decreased (non-AGP1/non-AGP2: -447.3(-1122.3/641.2)/-896.6(-1307.3/-510.8)). ∆Temperature findings were similar (AGP1/AGP2: 12.5(7.8/17.0)/9.3(1.8/15.3) versus non-AGP1/non-AGP2: -13.1(-18.7/0)/-14.7(-16.8/-6.8); ≤ 0.003)), while for ∆humidity, no significant difference ( > 0.05) was found.
Within the limitations of the study, the combination of HVE and EOS was similarly effective in controlling aerosol emissions of particles between one and ten micrometers in skill labs during AGPs versus that during non-AGPs. After AGPs, air exchange with the AC should be complemented by open doors for better air quality if natural ventilation through open windows is restricted.
本研究旨在分析在临床前牙科培训中自然通风受限的小型技能实验室里，在气溶胶产生操作（AGP）期间及之后控制空气质量的不同方法（气溶胶传播感染控制的最坏情况）。研究了不同阶段（AGP1：口腔内高流量吸引（HVE）；AGP2：HVE加口外移动清除器（EOS））以及之后的阶段（非AGP1：空调系统（AC），非AGP2：AC加开门）。
在两个夏季日（AGP组：n = 30；非AGP组：n = 30）期间，对PM1、PM2.5和PM10（μg/m）、二氧化碳浓度（ppm）、温度（K）和湿度（h）进行连续数据收集。在模拟我们的教学常规时，未定义空气参数的基础水平。因此，计算了每个参数的变化（Δ = [测量后]-[测量前]每小时）。
比较AGP2与AGP1时，我们发现ΔPM2.5和ΔPM1值存在显著差异（中位数（第25/75百分位数））（ΔPM2.5：1.6(0/4.9)/-3.5(-10.0/-1.1)，P = 0.003；ΔPM1：1.6(0.6/2.2)/-2.2(-9.3/-0.5)，P = 0.001）。在两个非AGP阶段之间，所测量的所有参数均无显著差异。所有AGP阶段的ΔCO均升高（AGP1/AGP2：979.0(625.7/1126.9)/549.9(4.0/788.8)），而非AGP阶段的值降低（非AGP1/非AGP2：-447.3(-1122.3/641.2)/-896.6(-1307.3/-510.8)）。Δ温度的结果相似（AGP1/AGP2：12.5(7.8/17.0)/9.3(1.8/15.3) 对比非AGP1/非AGP2：-13.1(-18.7/0)/-14.7(-16.8/-6.8)；P ≤ 0.003），而对于Δ湿度，未发现显著差异（P > 0.05）。
在本研究的局限性内，HVE和EOS的组合在AGP期间与非AGP期间的技能实验室中，对于控制1至10微米颗粒的气溶胶排放同样有效。AGP之后，如果通过开窗进行自然通风受限，使用空调进行空气交换时应辅以开门以获得更好的空气质量。
