Department of Interdisciplinary Medicine, University of Medicine Aldo Moro, 70124, Bari, Italy.
National Institute for Insurance Against Injuries at Work (INAIL), Bari, Italy.
BMC Pulm Med. 2022 Apr 27;22(1):161. doi: 10.1186/s12890-022-01948-6.
In dental laboratories, exposure to crystalline silica can occur during procedures that generate suspended mineral dusts, e.g. dispersion of mixing powders, removal of castings from molds grinding, polishing of castings and porcelain, and use of silica sand for blasting. There is also a large list of toxic agents (acrylic resins, polymeric materials, etc.) used to produce removable and fixed prostheses, but also impression materials and more. Using personal protective equipment and other aids reduces the exposure to these potentially harmful agents.
We report the case of a 42-year-old male dental technician who began to suffer from a dry cough and exertional dyspnea after approximately 15 years of work. The operations he conducted for his job resulted in the generation of crystalline silica, aluminum, chromium and titanium dust. The worker did not regularly wear personal protective equipment and some of the above operations were not carried out in closed circuit systems. The Chest X-ray showed diffused micronodules in the pulmonary interstitium of the upper-middle lobes, bilaterally, and a modest left basal pleural effusion. Simple spirometry showed small airway obstruction in its initial stage. High Resolution Computerized Tomography of the chest showed bilateral micronodulation of a miliariform type, with greater profusion to the upper lobes, also present in the visceral pleura, bilaterally. Histological examination showed aggregates of pigment-laden macrophages forming perivascular macules or arranged in a radial pattern around a core of sclerohyalinosis. Scanning Electron Microscopy and Energy Dispersive Spectrometry revealed several mineral particles, typically characterized by the presence of crystalline silica and metal aggregates. The environmental concentrations of total dust and its respirable fraction were all lower than the relative TLV-TWA-ACGIH, yet not negligible.
The above findings and a multidisciplinary assessment led to the diagnosis of mixed dust pneumoconiosis s/q with 2/2 profusion of occupational origin. This diagnosis in a dental technician was supported for the first time in literature by environmental exposure analysis.
在牙科实验室中，在产生悬浮矿物粉尘的过程中可能会接触到结晶二氧化硅，例如混合粉末的分散、铸件从模具中取出、铸件的打磨和抛光、以及使用硅砂进行喷砂。还有大量的有毒物质（丙烯酸树脂、聚合材料等）用于制作可摘义齿和固定义齿，还包括印模材料等。使用个人防护设备和其他辅助设备可以减少接触这些潜在有害物质的机会。
我们报告了一例 42 岁的男性牙科技术员的病例，他在大约 15 年的工作后开始出现干咳和劳力性呼吸困难。他所进行的工作会产生结晶二氧化硅、铝、铬和钛粉尘。该工人没有定期佩戴个人防护设备，并且一些上述操作未在闭路系统中进行。胸部 X 光显示双肺上叶和中叶的肺间质弥漫性微小结节，并有少量左侧基底部胸腔积液。简单的肺量计检查显示早期小气道阻塞。胸部高分辨率计算机断层扫描显示双侧粟粒状微结节，上叶更为弥漫，双侧胸膜也可见。组织学检查显示含色素的巨噬细胞聚集形成血管周围斑或呈放射状排列围绕着硬化素核心。扫描电子显微镜和能量色散光谱显示了几个矿物颗粒，通常具有结晶二氧化硅和金属聚集物的特征。总粉尘及其可呼吸部分的环境浓度均低于相对 TLV-TWA-ACGIH，但也不容忽视。
上述发现和多学科评估导致诊断为混合粉尘尘肺 s/q，职业性 2/2 级弥漫度。这是文献中首次支持牙科技术员的此类诊断，该诊断得到了环境暴露分析的支持。
