What is the Mantoux test (tuberculin skin test) used for?

The Mantoux test (purified protein derivative/PPD skin test) is used to detect previous exposure to Mycobacterium tuberculosis (TB). Purified protein derivative is injected intradermally, and the induration (hardness) is measured 48 to 72 hours later. A positive result (≥5, ≥10, or ≥15 mm depending on risk group) indicates prior exposure or infection. It does not distinguish between latent TB and active disease. Dental relevance: healthcare workers, including dental professionals, should undergo regular TB testing due to occupational exposure risk. An active TB patient should be treated in a respiratory isolation setting.