A clinical exam or new patient exam is more commonly referred to as a routine check up. This routine check up lets your dentist essentially take inventory of the overall health of your mouth and teeth and diagnose any potential problems you may have.
During the dental exam, the dentist examines your overall oral health and hygiene. The majority of problems with your teeth and the jawbone are not visible to the naked eye. That is why dental X ray plays an important role, and give the more accurate look at what is really going to be inside your mouth and below your teeth and gums. X-rays can help in checking for any bone loss and determine the grievousness of the gum disease.
In addition to revealing any problems that were not visible during the routine check up or clinical exam, these initial x-rays will also provide your dentist with a benchmark with which to compare against during your future visits.