Dental composites are widely used by dentists as restorative material to restore tooth fractures and dental caries or decay. Dental composites often contain advanced nanomaterials. After restoring a tooth, the dentist may use a high-speed handpiece to contour the surface of the composite through the process of drilling, utilizing various dental burs depending on the situation. Additionally, dentists must often remove existing composite restorations for numerous reasons (e.g., recurrent decay or need for a crown). If appropriate controls, such as water aerosol in conjunction with the grinding process and/or local exhaust ventilation, are inadequately utilized, both the dentist and patient may inhale airborne particles released in the drilling process. This study aimed to identify the potential exposure from dental procedures that utilize advanced nanocomposites and to characterize the particles released from commonly used dental composites. To identify the characteristics and elemental composition of the released particles, a uniquely designed nanoparticle sampler, a Sioutas cascade impactor, and real-time instruments were utilized. Both microscopic and size-fractionated concentration analyses confirmed the release of nanometer-sized particles consisting of various metal components that are potentially concerning for human exposure. These results elucidate the potential nanoparticle exposure that may occur during dental practice with advanced materials, based on simulated restoration grinding situations.

牙科复合材料被牙医广泛用作恢复性材料，以恢复牙齿的骨折和龋齿或龋齿。牙科复合材料通常包含先进的纳米材料。修复牙齿后，牙医可根据情况使用高速机头通过钻孔过程对复合材料的表面进行轮廓处理，利用各种牙钻。另外，牙医通常必须出于多种原因（例如，复发性腐烂或需要牙冠）去除现有的复合修复体。如果没有充分利用适当的控制措施，例如与研磨过程和/或局部排气通风相结合的水雾剂，则牙医和患者都可以吸入在钻孔过程中释放的空气中悬浮颗粒。这项研究旨在确定使用先进的纳米复合材料的牙科手术的潜在暴露，并鉴定从常用牙科复合材料释放的颗粒的特征。为了确定释放颗粒的特征和元素组成，使用了设计独特的纳米颗粒采样器，Sioutas级联撞击器和实时仪器。微观和大小分级浓度分析均证实释放了由各种金属组分组成的纳米级颗粒，这些金属组分可能对人体造成影响。这些结果基于模拟的修复体研磨情况，阐明了在牙科实践中使用高级材料时可能发生的纳米颗粒暴露。