The Vermont Office of Professional Regulation has revoked the license of a longtime dentist from South Burlington for unauthorized prescribing of controlled substances.

Dr. Randall Miller had been licensed since July of 1984, according to the Rutland Herald. However, state investigators recently filed unprofessional conduct charges against him, and he has agreed in writing to not contest those charges.

According to the newspaper, records show Dr. Miller prescribed controlled substances to patients for several years without ever signing up for the state program that would authorize him to do so. The records reportedly also show that most of the patients for whom Miller wrote the prescriptions had no documentation in their dental records of a medical need for the prescriptions.

Dr. Miller resigned in October from the Vermont Board of Dental Examiners, which investigates and resolves allegations of unprofessional conduct by dentists. He’d served on the state board since July 2010, which at the time of his resignation was the longest tenure of any of its 11 members.