X-rays allow us to 'see the unseen'. Many places like inbetween the teeth, beneath the gums and within the bone are not able to 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 significant of a problem, that if we had X-rays, perhaps we could have resolved the issue earlier, and with a better prognosis.