Is it okay to put the opalescence teeth whitening gel in a foil tray for one night?

I need to whiten but I dont have my correct trays right now, is it okay to make a foil tray and put the gel in that for the night?
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Actually i don't really agree with that. My reason is, we don't know if there is a possible reaction between the whitening gel and a foil tray that maybe a corrosive and dissolve the foil. You may get poisoned by the particles of the foil. The other reason, is there a guarantee that the foil is intact with the teeth while you were sleeping. There is a great risk for deattachment of the foil that expose you with the risk of swallowed either the foil and the whitening gel it self that maybe contain a corrosive agent for the alimentary tract epithelial surface.
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