I must strongly express my opposition to assistants treating patients by scaling.  It took me , and indeed  all of my fellow hygienists years of rigorous training, supervision, and testing to be declared proficient at scaling.  At best, an assistant without this training could succeed in removing some calculus.  At worst, the patient could suffer from a multitude of problems, including tissue trauma, burnished calculus, periodontal abcesses, and missed dietection of serious oral health problems.  Please don't risk patients health along with the dental professions reputation in order to save money not paying a hygienist salary.  We are paid well because we hold a license and as such are responsible for providing quality patient care that stems from years of specific education.   I would no more want an assistant scaling me than I would want my neighbor who works in a business office. Let dentists, hygienists, and assistants each  provide the patient care they were specifically trained!  Incidentally, I would not be comfortable if I were an assistant doing this procedure, no more than I would be comfortable as a hygienist in performing a root canal.