RDH Law and Ethics Test Bank
2026: 200 Practice Questions
Section 1: Legal Foundations & Scope of Practice
1. The primary legal authority that defines the scope of
practice for a Registered Dental Hygienist is the:
A) ADHA Code of Ethics
B) State Dental Practice Act
C) OSHA Bloodborne Pathogens Standard
D) CDC Guidelines
Answer: B
Rationale: The State Dental Practice Act is the law that legally
defines the scope of practice, supervision levels, and authorized
duties for dental hygienists in that specific state .
2. A registered dental hygienist (RDH) is permitted to
perform all of the following under general supervision
EXCEPT:
A) Preventive and therapeutic interventions, including oral
prophylaxis, scaling, and root planing
B) Taking impressions for bleaching trays and application and
activation of agents with nonlaser, light-curing devices
C) Application of topical, therapeutic, and subgingival agents used
for the control of caries and periodontal disease
D) Application of laser or light-curing devices for whitening
Answer: D
Rationale: While RDHs may apply bleaching agents and activate
them with nonlaser light-curing devices under general
,supervision, the use of lasers for whitening procedures is not
authorized for dental hygienists in California .
3. The range of activities that can be performed legally by a
dentist or dental auxiliary is referred to as:
A) Scope of practice
B) Practice Act
C) Supervision
D) Extended function
Answer: A
Rationale: Scope of practice defines the specific procedures,
treatments, and services that a licensed professional is legally
authorized to perform .
4. A licensed RDH is permitted to apply fluoride treatments
and dental sealants, in addition to performing oral
screenings, without supervision in which setting?
A) Public health program created by federal, state, county, or local
government entity
B) Private practice
C) Hospital setting
D) Any dental setting
Answer: A
Rationale: In public health settings established by government
entities, RDHs may apply fluoride and sealants and perform oral
screenings without direct supervision. This reflects a commitment
to expanding access to preventive care .
5. A dental hygienist who performs a procedure that is not
allowed by the state’s Dental Practice Act could be charged
with:
,A) Malpractice
B) Unlicensed practice of dentistry
C) Res ipsa loquitur
D) Vicarious liability
Answer: B
Rationale: Practicing beyond the legal scope is considered the
unlicensed practice of dentistry, even if the hygienist holds a
license, because the license does not grant permission for acts
outside the defined scope .
Section 2: Supervision & Legal Accountability
6. Which of the following is an example of "general
supervision"?
A) Hygienist performing SRP while dentist is across the room
B) Hygienist performing prophylaxis at a nursing home after the
dentist has examined the patient within the last 12 months
C) Hygienist administering local anesthesia without any prior
exam
D) Hygienist placing a restoration
Answer: B
Rationale: General supervision (or indirect supervision) means the
dentist has authorized the procedure and is available, but not
necessarily present. Off-site care like nursing homes often falls
under this .
7. A dentist is legally responsible for the negligent acts of the
dental hygienist under the doctrine of:
A) Respondeat superior
B) Contributory negligence
C) Assumption of risk
, D) Statute of limitations
Answer: A
Rationale: Respondeat superior ("let the master answer") holds an
employer liable for the acts of employees performed within the
scope of their employment .
8. The legal defense of "contributory negligence" means:
A) The patient was partly at fault for their own injury
B) The hygienist was not licensed
C) The dentist was also negligent
D) The injury was unavoidable
Answer: A
Rationale: Contributory negligence asserts that the patient's own
actions (e.g., failing to disclose a medical condition) contributed
to the harm .
9. A patient sues a hygienist for burning their lip with a curing
light, and there is no direct evidence of negligence. This is an
example of:
A) Res ipsa loquitur
B) Respondeat superior
C) Battery
D) Assault
Answer: A
Rationale: Res ipsa loquitur ("the thing speaks for itself") applies
when the accident is of a kind that ordinarily does not occur
without negligence (e.g., burning a patient's lip with a curing
light) .
Section 3: Licensing & Mandatory Reporting
2026: 200 Practice Questions
Section 1: Legal Foundations & Scope of Practice
1. The primary legal authority that defines the scope of
practice for a Registered Dental Hygienist is the:
A) ADHA Code of Ethics
B) State Dental Practice Act
C) OSHA Bloodborne Pathogens Standard
D) CDC Guidelines
Answer: B
Rationale: The State Dental Practice Act is the law that legally
defines the scope of practice, supervision levels, and authorized
duties for dental hygienists in that specific state .
2. A registered dental hygienist (RDH) is permitted to
perform all of the following under general supervision
EXCEPT:
A) Preventive and therapeutic interventions, including oral
prophylaxis, scaling, and root planing
B) Taking impressions for bleaching trays and application and
activation of agents with nonlaser, light-curing devices
C) Application of topical, therapeutic, and subgingival agents used
for the control of caries and periodontal disease
D) Application of laser or light-curing devices for whitening
Answer: D
Rationale: While RDHs may apply bleaching agents and activate
them with nonlaser light-curing devices under general
,supervision, the use of lasers for whitening procedures is not
authorized for dental hygienists in California .
3. The range of activities that can be performed legally by a
dentist or dental auxiliary is referred to as:
A) Scope of practice
B) Practice Act
C) Supervision
D) Extended function
Answer: A
Rationale: Scope of practice defines the specific procedures,
treatments, and services that a licensed professional is legally
authorized to perform .
4. A licensed RDH is permitted to apply fluoride treatments
and dental sealants, in addition to performing oral
screenings, without supervision in which setting?
A) Public health program created by federal, state, county, or local
government entity
B) Private practice
C) Hospital setting
D) Any dental setting
Answer: A
Rationale: In public health settings established by government
entities, RDHs may apply fluoride and sealants and perform oral
screenings without direct supervision. This reflects a commitment
to expanding access to preventive care .
5. A dental hygienist who performs a procedure that is not
allowed by the state’s Dental Practice Act could be charged
with:
,A) Malpractice
B) Unlicensed practice of dentistry
C) Res ipsa loquitur
D) Vicarious liability
Answer: B
Rationale: Practicing beyond the legal scope is considered the
unlicensed practice of dentistry, even if the hygienist holds a
license, because the license does not grant permission for acts
outside the defined scope .
Section 2: Supervision & Legal Accountability
6. Which of the following is an example of "general
supervision"?
A) Hygienist performing SRP while dentist is across the room
B) Hygienist performing prophylaxis at a nursing home after the
dentist has examined the patient within the last 12 months
C) Hygienist administering local anesthesia without any prior
exam
D) Hygienist placing a restoration
Answer: B
Rationale: General supervision (or indirect supervision) means the
dentist has authorized the procedure and is available, but not
necessarily present. Off-site care like nursing homes often falls
under this .
7. A dentist is legally responsible for the negligent acts of the
dental hygienist under the doctrine of:
A) Respondeat superior
B) Contributory negligence
C) Assumption of risk
, D) Statute of limitations
Answer: A
Rationale: Respondeat superior ("let the master answer") holds an
employer liable for the acts of employees performed within the
scope of their employment .
8. The legal defense of "contributory negligence" means:
A) The patient was partly at fault for their own injury
B) The hygienist was not licensed
C) The dentist was also negligent
D) The injury was unavoidable
Answer: A
Rationale: Contributory negligence asserts that the patient's own
actions (e.g., failing to disclose a medical condition) contributed
to the harm .
9. A patient sues a hygienist for burning their lip with a curing
light, and there is no direct evidence of negligence. This is an
example of:
A) Res ipsa loquitur
B) Respondeat superior
C) Battery
D) Assault
Answer: A
Rationale: Res ipsa loquitur ("the thing speaks for itself") applies
when the accident is of a kind that ordinarily does not occur
without negligence (e.g., burning a patient's lip with a curing
light) .
Section 3: Licensing & Mandatory Reporting
