In certain situations where a tooth has been missing for some time or there are no teeth present and we wish to have a precise measurement of the bone area underneath, we ask patients that they have something called a CT scan of the area. A traditional dental x-ray is 2 dimensional and has limitations as it only shows available bone height. A CT scan takes a 3-d image of the area that we are interested in. This tells us how wide and tall the bone area is and also reveals other important areas such as your sinuses, nerves near the planned surgery area.