[Animal modeling] - Experimental study on lung tissue damage in rats caused by dental grinding dust

  Objective To evaluate the effects of cobalt chromium molybdenum metal , zirconia porcelain and polymethyl methacrylate resin on lung injury in rats.

  Methods Scanning electron microscopy and laser particle size analyzer were used to detect the surface morphology and particle size of three dental dusts, and the rat model of dust exposure was established; Giemsa staining and enzyme-linked immunosorbent assay were used to detect the total number of leukocytes, the number of macrophages, and the content of interleukin-6 and interleukin-16 in bronchoalveolar lavage fluid of rats; HE staining was used to observe the pathological changes of lung tissue sections.

  Results The surface morphology and particle size distribution of three kinds of dental grinding dust particles were different, and the particle size of fine grinding dust particles decreased significantly; Compared with the control group, the number of leukocytes, macrophages and the contents of interleukin-6 and interleukin-16 in each dust exposed group were significantly increased. The inflammatory cells in the lung tissue of rats were infiltrated significantly, and the structure of lung tissue was damaged and fibrosis occurred; Compared with the non fine grinding group, the inflammatory cells and inflammatory factors in the fine grinding group of verapamil and zirconia dust increased significantly.

  Conclusion Three kinds of dental dusts before and after grinding can cause inflammatory injury and early fibrosis changes of lung tissue in rats exposed to dust, and the inflammatory injury of lung tissue in rats after fine grinding with verapamil and zirconia dust is enhanced compared with that before grinding.