Gutta Percha Composition — NDEB AFK MCQ
Instant feedback + full explanation. One question, done properly.
Educational content. Not a substitute for clinical judgement or local policy.
Reveal the answer and explanation
Correct answer: A — Trans-polyisoprene (beta form)
Dental gutta percha points are composed primarily of zinc oxide (~60-75%) as filler, with beta-phase trans-polyisoprene (~20%) as the polymer matrix, barium sulfate (~1-2%) for radiopacity, and wax/resins (~1-4%) for plasticity. Despite being called 'gutta percha,' the actual gutta percha (trans-polyisoprene) content is relatively small. The beta form is the stable room-temperature phase that is used clinically. Heating converts it to the alpha phase (used in thermoplasticised obturation techniques), and further heating produces the amorphous phase.
Reference: Torabinejad – Endodontics: Principles and Practice, 6th ed., 2021