# RDH Law and Ethics practice questions: Informed consent and patient rights

Five original RDH Law and Ethics practice questions on informed consent and patient rights, each answered on this page with a rationale and a source.

Last updated: 2026-07-25.

## Question 1

An adult patient agrees to quadrant scaling and root planing after the dentist's diagnosis. The hygienist explains the procedure, and the patient signs the office consent form — but no one mentions that root sensitivity and gingival recession commonly follow. The patient later sues, saying she would have chosen differently had she known. How would California law most likely characterize that claim?

- A. Battery, because a preprinted signature form can never establish valid consent.
- B. Battery, because a material risk was left out of the conversation.
- C. Professional negligence, because consent existed but the disclosure was left incomplete.
- D. No claim at all, because a signed consent form ends the provider's disclosure duty.

**Answer C:** Professional negligence, because consent existed but the disclosure was left incomplete.

California's informed-consent doctrine splits the two failure modes: treating with no consent at all (or performing a substantially different procedure) is battery, while obtaining consent without disclosing material risks is professional negligence.

**Common trap:** a signed form is evidence that a conversation happened, never a substitute for the disclosure itself.

Source: [Cobbs v. Grant (1972) 8 Cal.3d 229 — California informed-consent doctrine: the duty of reasonable disclosure of available choices and their dangers,…](https://scocal.stanford.edu/opinion/cobbs-v-grant-30236)

## Question 2

A patient arrives with pain from an inflamed, tender area of gingival tissue. The dentist diagnoses the condition and orders debridement of the area. The patient is alert, oriented, and conversing normally. The hygienist wants to begin at once, reasoning that pain makes this an emergency and consent can wait. What does California informed-consent law require?

- A. Nothing further, because treatment aimed at relieving pain is exempt from consent requirements.
- B. A disclosure conversation and the patient's informed consent before instrumentation begins.
- C. Written consent witnessed by the supervising dentist, because pain may impair the patient's judgment.
- D. Consent obtained after the appointment, as long as the hygienist documents it the same day.

**Answer B:** A disclosure conversation and the patient's informed consent before instrumentation begins.

consent must exist before treatment, and the emergency exception is narrow — it covers a patient who cannot consent when care cannot wait, not a conversant patient in discomfort.

**Common trap:** "it's urgent" is the most common exam excuse for skipping a conversation that was plainly possible.

Source: [Cobbs v. Grant (1972) 8 Cal.3d 229 — California informed-consent doctrine: the duty of reasonable disclosure of available choices and their dangers,…](https://scocal.stanford.edu/opinion/cobbs-v-grant-30236)

## Question 3

A hygienist has already disclosed the dental hygiene care plan, its material risks, its benefits, and the option of doing nothing — disclosure that meets California's objective prudent-patient standard. Which step is the strongest practice for confirming the patient actually took the information in?

- A. Handing the patient a detailed printed brochure on periodontal disease and having her initial the last page.
- B. Delivering a thorough scientific explanation of the microbiology of periodontal infection and its treatment.
- C. Asking "Do you have any questions?" and charting that the patient verbalized understanding of the care plan.
- D. Asking the patient to describe the plan and its main risks in her own words, then correcting the gaps.

**Answer D:** Asking the patient to describe the plan and its main risks in her own words, then correcting the gaps.

the item asks about practice, not the legal test, and the stem says so. Cobbs v. Grant sets an objective standard — reasonable disclosure of the material choices and dangers a prudent patient would need — and it does not make proof of this patient's subjective comprehension the measure of a provider's duty. That legal duty was already satisfied here. Teach-back is the strongest of the four for actually confirming uptake, and it is good communication, ethical, and risk-management practice, which is why option D is the credited answer.

**Common trap:** do not invert this into "understanding is the legal test." Brochures and a charted "verbalized understanding" are the weakest of the four as practice, but the reason D wins is its quality as practice, not a rule that consent fails without demonstrated comprehension.

Source: [Cobbs v. Grant (1972) 8 Cal.3d 229 — California informed-consent doctrine: the duty of reasonable disclosure of available choices and their dangers,…](https://scocal.stanford.edu/opinion/cobbs-v-grant-30236)

## Question 4

A registered dental hygienist in a Sacramento general practice is about to begin scaling and root planing on a new adult patient. Under California law, what determines whether her pre-treatment disclosure was legally adequate?

- A. Whatever other hygienists in this community customarily tell patients before scaling and root planing, as shown by expert testimony on local custom.
- B. What a reasonable person in this patient's position would need to know — the procedure, its material risks, its benefits, and the available alternatives.
- C. Whatever the supervising dentist's written office consent policy lists as the required talking points for periodontal therapy here.
- D. A complete scientific explanation of periodontal pathology, instrumentation technique, and healing biology, given before she signs.

**Answer B:** What a reasonable person in this patient's position would need to know — the procedure, its material risks, its benefits, and the available alternatives.

Cobbs v. Grant imposes "a duty of reasonable disclosure of the available choices with respect to proposed therapy and of the dangers inherently and potentially involved in each," measured from the patient's side of the chair rather than from professional custom. The available choices expressly include the option of no treatment, which is why declining care is one of the alternatives the disclosure must put in front of the patient. The same case caps the duty at the other end: "a mini-course in medical science is not required."

**Common trap:** Option A is the professional-custom (physician-based) standard used in some other states and in stale prep; California uses the reasonable-patient standard. Option D over-corrects into the mini-course Cobbs expressly rejects, and Option C confuses an internal office policy with the legal measure of disclosure.

Source: [Cobbs v. Grant (1972) 8 Cal.3d 229 — California's informed-consent doctrine: the duty of reasonable disclosure of available choices and their…](https://scocal.stanford.edu/opinion/cobbs-v-grant-30236)

## Question 5

At an elementary school event in Fresno, a hygienist is performing oral health screenings without supervision. A parent looks at her child's screening form and asks, "So she has two cavities — should we get them filled?" What is the hygienist's correct response?

- A. Confirm that the child has two carious lesions on the screening form and recommend that the parent schedule composite restorations soon.
- B. Explain that a screening is not a diagnosis and refer the child to a dentist for a comprehensive examination, diagnosis, and treatment plan.
- C. Obtain the parent's written informed consent for restorative treatment now, so that the referral appointment is not delayed by paperwork later.
- D. Decline to discuss the findings at all, because screening results are confidential and may not be shared with a parent at a school event.

**Answer B:** Explain that a screening is not a diagnosis and refer the child to a dentist for a comprehensive examination, diagnosis, and treatment plan.

BPC § 1911 authorizes screenings without supervision and builds in the duty to "refer any screened patients with possible oral abnormalities to a dentist for a comprehensive examination, diagnosis, and treatment plan." The practice of dental hygiene expressly excludes "[d]iagnosis and comprehensive treatment planning," so the hygienist may explain what a screening is and is not, but may not supply the diagnosis the parent is asking for.

**Common trap:** Options A and C read as helpful patient education, which is exactly why candidates pick them — but both put a diagnosis and a treatment plan in the hygienist's mouth, which is a scope violation, not good consent practice. Option D confuses this with a confidentiality question; the parent of a screened minor is not being denied information, the hygienist simply cannot convert a screening into a diagnosis.

Source: [Cal. Bus. & Prof. Code § 1911 — Services Provided Without Supervision: education, oral health training, and screenings, with the subdivision (b) duty…](https://leginfo.legislature.ca.gov/faces/codes_displaySection.xhtml?sectionNum=1911.&lawCode=BPC)

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Official reference: [DHBC/PSI RDH Laws and Ethics Written Examination Candidate Information Bulletin](https://www.dhbc.ca.gov/formspubs/candidate_handbook.pdf). Original exam-style questions written for study, never recalled exam content. Independent educational preparation, not legal advice, and not affiliated with or endorsed by the Dental Hygiene Board of California or PSI. Confirm current requirements with the Dental Hygiene Board of California.