Studies on the biological response of fumes and airborne particulates from dental materials during their routine use.

本研究的目的是研究牙科材料铸造或抛光过程中产生的颗粒对小鼠巨噬细胞形态和活性的影响。小鼠腹腔巨噬细胞在添加10%胎牛血清的Eagle‘s MEM中培养，24小时后与镍铬合金颗粒孵育。镍铬合金颗粒暴露24小时后，巨噬细胞存活率明显下降。吞噬后，含Be的镍铬合金较不含Be的镍铬合金有更多的细胞死亡。我们还研究了PMMA颗粒对大鼠腹膜巨噬细胞形态、活力和超氧化物释放的影响。将大鼠巨噬细胞置于含20%胎牛血清的RPMI1640溶液中，分别暴露于200、500和1500µg/ml的颗粒物中90分钟。在形态实验中，将巨噬细胞用2.5%的戊二醛固定在0.1M、pH 7.4的磷酸盐缓冲液中，并进行透射或扫描电子显微镜观察。在超氧化物歧化释放实验中，巨噬细胞在37ﾟC的缓冲液中孵育90min，用细胞色素还原测定法测定超氧化物歧化酶的释放量。扫描电子显微镜观察表明，巨噬细胞吞噬PMMA或Ostron颗粒。暴露90分钟后，巨噬细胞释放的超氧阴离子从157.6(Sy.+-)3.1增加到212.5(Sy.+-)12.2N摩尔/mg蛋白。Ostron颗粒还可诱导巨噬细胞释放O_2~-。综上所述，牙科诊所产生的颗粒物可能是由于大量颗粒物的吞噬而引起细胞损伤和细胞死亡。

The purpose of this study was to investigate the effect of particlaties from vaporizing in casting or polishing of dental materials on the morphology and viability of murine macrophages. The mice peritoneal macrophages were cultured in Eagle's MEM supplemented with 10% fetal calf serum and incubated for 24 hrs later with Ni-Cr alloy particles. Cell viability of the macrophages was significantly decreased following 24hr exposure of Ni-Cr alloy particles. After phagocytosis more cell death were observed when the Ni-Cr alloy with Be was compared to the Ni-Cr alloy without Be. We also studied the effect of PMMA particles on cell morphology, viability and superoxide release of rat peritoneal macrophages. Rat macrophages in RPMI 1640 supplemented with 20% fetal bovine serum were exposed to 200, 500 and 1500 mug/ml particles for 90 min. For the morphological experiment the macrophages were fixed with 2.5% glutaraldephyde in 0.1 M phosphate pH 7.4 buffer and processed for transmission or scanning electrom microscopy. For the superoxide release experiment, macrophages were incubated in the buffer solution for 90 min at 37ﾟC.The amount of superoxide released was determined by the reduced cytochrome assay. Studies with SEM and TEM indicated that the macrophages phagocytosed PMMA or Ostron particles. Superoxide release from the macrophages was increased from 157.6(〕SY.+-.〔)3.1 to 212.5(〕SY.+-.〔)12.2n mole/mg protein after 90 min of exposure to the PMMA particles. Ostron particles also induced the O_2^- release from the macrophages. In conclusion, it can be stated that particles generated in dental clinics may be caused cell damage and cell death due to phagocytosis of large amount of particles.