Final answer:
Under general supervision, an RDH may perform various preventive and therapeutic dental hygiene services as permitted by state dental laws, without the dentist being directly present.
Step-by-step explanation:
The duties that an RDH (Registered Dental Hygienist) is authorized to perform under general supervision may vary by jurisdiction, but generally include preventive and therapeutic services such as dental cleanings, applying preventative materials, conducting initial periodontal assessments, and educating patients on oral hygiene.
The specific question about the duties of an RDH under general supervision seems to be contextualized wrong as it includes terms more relevant to nursing such as 'direct supervision of a registered nurse' and 'dialysis treatments'. However, focusing on dental hygiene, the correct answer would likely be basic oral hygiene tasks or any dental hygiene procedure allowed by the state's practice act that doesn't require direct supervision.