What is a primary difference between direct and indirect pulp therapy?

• A. Direct pulp therapy treats an exposed pulp; indirect pulp therapy treats near-exposed pulp without exposure to preserve vitality.
• B. Direct therapy cures tooth decay; indirect therapy cures gum disease.
• C. Direct therapy uses lasers; indirect uses magnets.
• D. Direct therapy is for primary teeth; indirect is for permanent teeth.

Answer: (A)

The main idea is the pulp’s exposure status. Direct pulp therapy places a protective material directly over an exposed pulp to try to keep it alive after injury or caries. Indirect pulp therapy is used when the caries is so close to the pulp that there is no actual exposure; a thin layer of dentin is left intact and a protective barrier is placed to encourage dentin formation and preserve vitality without exposing the pulp. So the difference hinges on whether the pulp is exposed (direct) or not exposed (indirect) and the corresponding goal of preserving vitality.