Which statement about Alzheimer disease is CORRECT?

Correct answer: C. Patients experience aphasia (language impairment) and apraxia (loss of learned motor skills)

• A. The opposite is true. Oral care becomes progressively more difficult, with rising caries and periodontal disease, aspiration risk, and eventually complete dependence on caregivers.
• B. The reverse is true. Alzheimer is the most common cause of dementia (roughly 60–80%), but dementia also results from vascular disease, Lewy body disease, frontotemporal degeneration, and other causes.
• C. CORRECT. Alzheimer disease produces progressive cortical dysfunction across multiple domains — the classic 'four A's': AMNESIA (memory loss), APHASIA (language), APRAXIA (loss of learned motor sequences, including toothbrushing), and AGNOSIA (failure of recognition). Apraxia has direct dental relevance: the patient loses the ability to perform the motor sequence of oral hygiene, and eventually to manage a toothbrush or a denture at all.
• D. Late-onset Alzheimer typically presents after age 65; early-onset familial forms are rare and still usually present after 40.

Note: Practical dental management: short morning appointments, simple one-step instructions, caregiver-delivered hygiene, high-fluoride toothpaste, and early planning while the patient can still consent.