Figure 1.

Lethal concentration (LC) 50 determined using a series of oral rinse dilutions and oral rinse additives applied to gingival fibroblasts and L929 and HSC-2 cells. (a, d) Gingival fibroblasts, (b) L929 cells, and (c) HSC-2 cells were cultured overnight and exposed to selected oral rinse dilutions and oral rinse additives for 2 minutes. Cell viability was measured with a formazan formation assay. Statistical analysis was performed, and LC50 was calculated. Graphs show a box plot, for example, the box represents the first and third quartiles, the median separating the higher half of a data from the lower half, and the whiskers indicate the minimum and maximum of the data. For oral rinses #1 and #2, cells remained vital; therefore the LC50 was not calculable and was excluded. For all experiments, cells with less than 10 passages were used. At least five independent experiments for each cell line were performed.