ABSTRACT

Objective: We designed an in vitro study to evaluate the efficiency of an 0.5 vol% hydrogen peroxide-based spray in reducing Coronavirus 229E spread during a conventional dental procedure.

Methods: A class III cabinet-like chamber was custom-built, using phantoms for both patient and operator. A suspension of HCoV-229E in artificial saliva having a similar viral load to SARS-CoV-2 asymptomatic patients was inoculated inside the patient’s phantom mouth. A 10 s-lasting dental procedure was performed using an aerosol-generating air-turbine, with or without high-volume evacuation (HVE). The effect of 0.5 vol% H₂O₂ cooling spray in reducing viral loads was tested. Viral presence on the operator phantom was assessed by Real-Time quantitative PCR on the mask’s outer surface, on the phantom’s forehead, and inside its mouth.

Results: When the H₂O₂ cooling spray was used, as compared to the conventional spray, viral loads were significantly lower on all tested sites, falling below the detection limit. Viral loads did not significantly change in any tested site when HVE was used.

Conclusion: The use of 0.5 vol% H₂O₂ cooling spray by dental handpieces drastically reduced the possibility of coronaviruses spread during aerosol-generating dental procedures. This strategy deserves further consideration among the preventive measures to be adopted during the SARS-CoV-2 pandemic.

摘要

目的：我们设计了一项体外研究，以评估基于 0.5 vol% 过氧化氢的喷雾剂在传统牙科手术中减少冠状病毒 229E 传播的效率。

方法：定制了一个 III 类柜式腔室，对患者和操作员使用幻影。将与 SARS-CoV-2 无症状患者具有相似病毒载量的人工唾液中的 HCoV-229E 悬浮液接种在患者的幻嘴内。使用产生气溶胶的空气涡轮机进行了持续 10 秒的牙科手术，有或没有大容量抽真空 (HVE)。测试了 0.5 vol% H ₂ O ₂冷却喷雾在降低病毒载量方面的效果。通过面罩外表面、模型前额和嘴巴内部的实时定量 PCR 评估操作者模型上的病毒存在。

结果：当使用 H ₂ O ₂冷却喷雾时，与常规喷雾相比，所有测试部位的病毒载量显着降低，低于检测限。使用 HVE 时，任何测试站点的病毒载量都没有显着变化。

结论：牙科手机使用 0.5 vol% H ₂ O ₂冷却喷雾大大降低了冠状病毒在产生气溶胶的牙科手术过程中传播的可能性。在 SARS-CoV-2 大流行期间采取的预防措施中，该策略值得进一步考虑。