I strongly oppose the duties of dental assistants becoming expanded to scaling patients.  I believe this would greatly decrease the degree of care that patients receive.  Hygienists have been adequately trained and educated to perform dental hygiene duties.  You should remember scaling teeth does not  just involve the mouth but the overall health of patients.  Which is want RDHs are trained and educated to perform.  I especially like the comment from another RDH that dentists do not want RDHs to have restorative duties.  Please just think professionally before considering that dental assistants should be able to scale.