S.C. Code Ann. § 40-15-290

A dentist ordering dental technological work to be performed off his premises shall issue therefor a work authorization. A copy of each work authorization shall be retained in a file by the issuing dentist for a period of at least three years. The work authorization copy shall be available for inspection by the board, or its duly authorized agents, on the premises during such period. Any dentist who fails to write and retain the above written work authorization or refuses to allow the board, or its duly authorized agents, to inspect the same, will be subject to the revocation or suspension of his license as herein provided.