The Iowa Dental Board has fined a Newton dentist for illegally delegating certain procedures to an unauthorized assistant, placing his license in a probationary status for two years, according to documents provided Wednesday to the Daily News.

Dr. Robert Benson, who operates a dental practice on the courthouse square in Newton, was accused in September of 2011 of allowing a dental assistant to perform duties which were beyond the “legal scope of practice.” Section 20.3(2)e of the Iowa Code outlines the limitations on services provided by dental assistants.

Specifically, with regard to allegations against Benson, the code prohibits assistants from rendering the “removal of any plaque, stain, or hard natural or synthetic material except by toothbrush, floss or rubber cup coronal polish, or removal of any calculus.” Agents of the Iowa Dental Board inspected Benson’s practice, at which time he told investigators his dental assistant had not performed such procedures.