I do not think that adding scaling to the duties of a dental assistant is a safe idea.  Much training and school competencies are needed to become proficient at scaling.  Hygienists have this training as well as training in the areas of pharmacology, medical emergencies, infection and immunity.  There is a reason these classes are required as part of our license.  The main reason is for patient SAFETY.  How can this education be discounted and patient safety thrown asside in order to expand the dutues of a dental professional who already has considerable duties?