All dental hygienists licensed under N.C. Gen. Stat. § 90-225 shall be required to attend Board-approved courses of study in subjects relating to dental hygiene.  The Board shall have authority to consider and approve courses, or providers of courses, to the end that those attending will gain (i) information on existing and new methods and procedures used by dental hygienists, (ii) information leading to increased safety and competence in their dealings with patients and supervising dentists, and (iii) information on other matters, as they develop, that are of continuing importance to the practice of dental hygiene as a part of the practice of dentistry.  The Board shall determine the number of hours of study within a particular period and the nature of course work required.  Failure to comply with continuing education requirements adopted under the authority of this section shall be grounds for the Board to decline to issue a renewal certificate under N.C. Gen. Stat. § 90-227 (1993, c. 307, s. 3.)