X-rays allow us to 'see the unseen'. Many places, like in between the teeth, beneath the gums, and within the bone are not be visualised in regular examination. By having regular X-rays, we are able to pick up on problems before they become larger problems, and can often manage things more conservatively as a result. By the time problems are visible to our eyes in an exam, they're often becoming quite a significant problem, which, if we had X-rays, perhaps we could have resolved the issue earlier, and with a better prognosis.