Checchi Vittorio, Montevecchi Marco, Checchi Luigi
Department of Surgery, Medicine, Dentistry and Morphological Sciences-Unit of Dentistry and Oral-Maxillo-Facial Surgery, University of Modena and Reggio Emilia, 41125 Modena, Italy.
Department of Biomedical and Neuromotor Sciences-Unit of Dentistry, University of Bologna, 40100 Bologna, Italy.
Dent J (Basel). 2021 Mar 24;9(4):36. doi: 10.3390/dj9040036.
Since aerosol continuously persists in dental settings, where different procedures and patients come in succession, the use of oronasal masks is highly recommended. Among them, respirators known as Filtering Face Pieces (FFP) show a protective superiority compared to surgical masks. Even concerning respirators classified as non-reusable, it is not known how many hours of use are necessary to compromise their filtering capacity. The aim of this study is to investigate the variations of filtering capacity of an FFP2 respirator over time, in order to safely optimize the timing of its use. Five respirators were worn by the same operator during clinical activity for different usage times (8, 16, 24, 32, 40 h), and one respirator was kept unused. All respirators underwent a bacterial filtration efficacy (BFE) test. T-test for paired data with Bootstrap technique and Wilcoxon test for paired data compared BFE values of the five tested FFP2s respectively at each time, and the areas with the corresponding values of the control respirator (FFp2-F). A generalized linear mixed effect model (GLM) was applied considering type of respirator and time as fixed effects and intercept as random effect. No significant statistical differences were present in the BFE of each time. Data obtained by the present study highlight the important ability of FFP2s to maintain their BFE over time, suggesting a long lasting protective function.
由于气溶胶在牙科环境中持续存在，不同的操作和患者相继而来，因此强烈建议使用口鼻面罩。其中，被称为过滤面罩（FFP）的呼吸器比外科口罩具有更高的防护优势。即使对于不可重复使用的呼吸器，也不清楚使用多少小时会损害其过滤能力。本研究的目的是调查FFP2呼吸器过滤能力随时间的变化，以便安全地优化其使用时间。在临床活动期间，同一名操作人员佩戴五个呼吸器，使用不同的时间（8、16、24、32、40小时），并保留一个未使用的呼吸器。所有呼吸器都进行了细菌过滤效率（BFE）测试。采用带Bootstrap技术的配对数据t检验和配对数据Wilcoxon检验分别比较五个测试FFP2在每次测试时的BFE值，以及对照呼吸器（FFp2-F）相应值的区域。应用广义线性混合效应模型（GLM），将呼吸器类型和时间视为固定效应，截距视为随机效应。每次测试的BFE均无显著统计学差异。本研究获得的数据突出了FFP2随时间维持其BFE的重要能力，表明其具有持久的保护功能。
