S.C. Code Ann. § 40-15-300

No person other than a licensed dentist, a student in an accredited dental school, or the recipient patient shall have in his possession any prosthetic or orthodontic model, impression, or appliance on which dental technological work has been, is being, or will be performed without having in his possession a properly executed written work authorization therefor. The board has authority to inspect the premises of any person licensed or registered by the board to insure compliance with this section. Nothing in this section precludes a certified or qualified dental assistant or licensed dental hygienist from taking impressions for dental study casts under the direct supervision of a licensed dentist present on the premises.