CONCORD — The man who headed Allcare Dental, which shut down offices in 13 states without notice Jan. 1, 2011, has surrendered his license to practice dentistry in New Hampshire. Allcare’s New Hampshire offices were in Manchester and Nashua.

Attorney General Michael Delaney said Robert Bates, who incorporated Allcare in New Hampshire in 2006, shortly after obtaining a New Hampshire dental license, surrendered his license as part of a consent decree signed May 9.

Bates was president of Allcare Dental Management LLC and Allcare Dental and Dentures of NH PC. His license surrender, approved by the New Hampshire Board of Dental Examiners. resolves allegations of professional misconduct that were scheduled for a disciplinary hearing before the board.

Patients learned of the closures when they arrived for appointments and found a note on the door that the offices were closed.

Allcare, which was based in the Buffalo, N.Y., area, filed for chapter 7 bankruptcy protection (liquidation) in U.S. Bankruptcy Court in Buffalo in November 2011.

After Allcare closed, the New Hampshire Department of Justice and the Board of Dental Examiners received more than 143 complaints from patients who had incomplete dental treatment discontinued.

At the time of the closing, many of the patients had had their teeth extracted and were waiting for permanent dentures they never received. Many of them had prepaid for dental care they did not receive, with one patient telling the New Hampshire Union Leader that if patients did not have the money available, Allcare arranged loans for them.

Under New Hampshire law, Dr. Bates was “practicing dentistry” even though he did not treat patients in the state and was therefore responsible for his and Allcare’s failures to fulfill various legal and ethical duties arising when a dental practice closes.

Under the consent decree, Bates acknowleged that he and Allcare failed to inform patients prior to the closure, that neither he nor Allcare provided any further treatement to Allcare patients after the closure, and that he and Allcare failed to be available to provide emergency care to patients following the closure.

Bates has also been the subject of actions taken by the dental licensing boards of Massachusetts, West Virginia and North Dakota. In 2010, the company paid $135,000 to Pennsylvania to settle a lawsuit the state filed against it.