Sorry, but no. X-rays have shorter wavelength than UV, much shorter than visible light. This equates to higher energy per photon, which is part of why they penetrate more than visible light (another way to look at this is that there are few electrons in most solids that can absorb a photon at such a short wavelength). Their resolving power, however, is much finer than visible; that's why x-rays are used to lay down the traces on integrated circuits that need to be smaller than a wavelength of visible light.
I wouldn't expect X-ray film to have less resolution than camera film, either. It's slow, which mean fine grain. Lack of sharpness, when present, is entirely due to the second emulsion on double-sided films -- the back side gets an exposure that's slightly diffused by the translucent emulsion on the front, like putting a frosted acetate over your negative and a clear one under to get an unsharp mask. If you could make the second emulsion's exposure and contrast enough lower than those of the front, you'd get a built-in USM with double-sided x-ray film.
For USM to work properly, the backside second emulsion would need to be a soft positive image.
I have stripped that backside emulsion after development, and the image is a bit sharper looking... and grainier. If you read the densities before and after stripping, the stripped version has exactly half the density. My understanding is the second emulsion is only there to increase the speed, or the sensitivity of the film when exposed with screens.