I'm going to also throw anecdotes into the bucket: three dentists completely missed a cavity on one of my rear molars (wisdom teeth) until I mentioned pain, and then they poked around physically and said, "oh yeah, that's a big one."
What kind of dental x-rays they took? Panoramic (shows the whole row of teeth in one image), CBCT (volumetric 3D) or intraoral (a digital sensor or film was put inside your mouth)?