N.C. Gen. Stat. § 90-31
The laws of North Carolina now in force, having provided for the annual renewal of any license issued by the North Carolina State Board of Dental Examiners, it is hereby declared to be the policy of this State, that all licenses heretofore issued by the North Carolina State Board of Dental Examiners or hereafter issued by said Board are subject to annual renewal and the exercise of any privilege granted by any license heretofore issued or hereafter issued by the North Carolina State Board of Dental Examiners is subject to the issuance on or before the first day of January of each year of a certificate of renewal of license.
On or before the first day of January of each year, each dentist engaged in the practice of dentistry in North Carolina shall make application to the North Carolina State Board of Dental Examiners and receive from said Board, subject to the further provisions of this section and of this Article, a certificate of renewal of said license.
The application shall show the serial number of the applicant's license, his full name, address and the county in which he has practiced during the preceding year, the date of the original issuance of license to said applicant and such other information as the said Board from time to time may prescribe, at least six months prior to January 1 of any year.
If the application for such renewal certificate, accompanied by the fee required by this Article, is not received by the Board before January 31 of each year, an additional fee shall be charged for renewal certificate. The maximum penalty fee for late renewal is set forth in G.S. 90-39. If such application, accompanied by the renewal fee, plus the additional fee, is not received by the Board before March 31 of each year, every person thereafter continuing to practice dentistry without having applied for a certificate of renewal shall be guilty of the unauthorized practice of dentistry and shall be subject to the penalties prescribed by G.S. 90-40.
N.C. Gen. Stat. § 90-31