Scope of Practice for Dental Hygienists and Supervision Levels
The hygiene scope
Michigan defines dental hygiene as services performed under a dentist's supervision, including prophylactic removal of calculus and stains, scaling and root planing, fluoride application, sealants, radiographs, patient education, and, only with additional authority, local anesthesia and nitrous oxide. The hygienist may not diagnose, treatment plan, prescribe, or perform surgical procedures.
Supervision levels
Direct supervision means the dentist is physically present in the office, has examined the patient, and is available. Indirect supervision usually means the dentist has authorized the procedure and is available by phone but is not on the premises. General supervision means the dentist has authorized the service but is not required to be present. The level required depends on the procedure and the setting; do not assume one level covers all hygiene services.
Worked example
A hygienist in a school-based program wants to apply sealants. The dentist has examined the children and written a protocol. If the Board rule for that service permits general supervision in that setting, the hygienist may proceed. If the rule requires direct supervision, the dentist must be present. The answer turns on the rule for sealants, not on the hygienist's comfort level.
Traps
There is no independent hygiene practice in Michigan. Do not use indirect and general interchangeably. Local anesthesia and nitrous oxide require direct supervision even when the hygienist holds the additional authority. Radiographs require a dentist's order and the appropriate supervision level.