A patient with Down syndrome has a documented history of difficult behaviour management. Which of the following is CONTRAINDICATED?

Correct answer: B. Physical restraint applied without informed consent and a documented protocol

• A. A rubber dam is positively indicated — it improves isolation and protects the airway in a patient who may have difficulty with instructions.
• B. CORRECT. Protective stabilization is never a convenience measure. It requires specific informed consent, a documented clinical justification, defined duration limits, and continuous monitoring. Applied ad hoc to manage difficulty, it constitutes restraint without consent and is both an ethical and a legal violation.
• C. Local anaesthesia is not contraindicated. Adequate anaesthesia is one of the most effective behaviour management tools available.
• D. Nitrous oxide is a reasonable and commonly used adjunct, though a large tongue and airway anatomy warrant attention.

Note: Down syndrome considerations that DO change your practice: atlantoaxial instability in roughly 10–20% — avoid neck hyperextension and excessive head manipulation; congenital cardiac defects — check whether the specific lesion requires endocarditis prophylaxis; macroglossia and airway narrowing; and early-onset, rapidly progressive periodontitis.