Patterson Dental Supply, Massachusetts General Hospital’s (MGH) vendor that provides software to the hospital to manage dental practice information, has reportedly admitted that approximately 4,300 of MGH’s patient records have been accessed by an unauthorized individual who “gained access to electronic files on the company’s systems in early February.”

The information compromised included patient names, dates of birth, Social Security numbers, and for some patients, the type of dental appointment, provider name, and medical record numbers.

Despite the fact that the unauthorized access was to Patterson Dental Supply’s system, MGH began notifying patients on June 29, 2016, and set up a call in center to answer patients’ questions.