A patient with autism, treated with amphetamine salts, is brought in by his mother who reports self-injurious behaviour with bite marks on his arms. He plays basketball. What intervention is most appropriate?

Correct answer: A. A custom-fabricated mouthguard

• A. CORRECT. A custom MOUTHGUARD serves both needs at once. It is a recognised protective appliance for self-injurious biting in patients with autism or developmental disability, shielding the lips, tongue and arms from the dentition, and it simultaneously provides the sports protection appropriate for a basketball player. It is reversible, non-invasive and preserves the dentition.
• B. Chlorhexidine manages plaque and gingival inflammation. It has no effect on self-injurious behaviour or on trauma from biting.
• C. Composite build-ups do not address the behaviour and would themselves be subject to fracture.
• D. Extraction of sound teeth for behavioural reasons is disproportionate, irreversible and ethically indefensible when a reversible protective appliance exists.

Note: Self-injurious behaviour also warrants a behavioural referral, and stimulant medication is worth reviewing with the prescriber, since amphetamines can aggravate bruxism and repetitive behaviours. Note the additional dental relevance of stimulants: xerostomia and consequent caries risk.