You’ve hit the candy and ice cream a little too hard - and now it’s time to face the music at the dentist over those cavities. Nearly 90 percent of American adults, aged 20-64, have had decay in their teeth that can leave them vulnerable to infection and even heart disease , according to federal data . Using a drill can help dentists clean and sterilize the area before applying a resin or metal filling to restore the decayed tooth. But there are some things patients should be aware of before they decide to go under the dental drill, according to experts. For one, not all cavities need a filling, and many people don’t need them right away. Yet, waiting too long may spell disaster. Although, maybe not for dentists. A dentist treats a patient in March 2017 in Denver, Colorado. Experts say that there are several things patients should know before they have a cavity treated (AFP/Getty) Dentistry is a business and surgical procedures rack up higher bills than a cleaning or X-ray.…