By Dan Breitwieser, WCJB TV 20 News.

Officials say they discovered an intruder had illegally accessed the main server at the College of Dentistry on October 3rd. The security breach involves an estimated 80% to 90% of current and former patients at both Gainesville clinic locations, as well as dental clinics in Jacksonville, St. Petersburg and Hialeah.

"We have no evidence that any of the information was misused," says UF College of Dentistry Dean Teresa Dolan. "We do know that someone had the potential to access it."

University police and FBI detectives are investigating, but they don't know who did it.

Almost all patients will be getting a letter in their mail in the next day or two, but there are about 8,000 patients who the college was unable to send a letter to.

The college has set up a hotline to take patient questions at (866) 783-5883.