INBDE (Integrated National Board Dental Examination) Practice Exam

Disable ads (and more) with a membership for a one time $2.99 payment

Ace your INBDE with our comprehensive practice exam. Featuring detailed explanations, interactive flashcards, and a wide array of multiple-choice questions designed to mirror the real test. Get ready to surpass your expectations!

Each practice test/flash card set has 50 randomly selected questions from a bank of over 500. You'll get a new set of questions each time!

Practice this question and more.

What contributes to primary resistance form?

Converging internal line angles, 45 degree cavosurface margin
Rounded internal line angles, 90 degree cavosurface margin
Parallel walls, 90 degree cavosurface margin
Undercuts, 90 degree cavosurface margin

The correct answer is: Rounded internal line angles, 90 degree cavosurface margin

Primary resistance form is a key factor in achieving a successful and long-lasting restoration. It refers to the shape and positioning of the preparation walls that provide stability and resistance to displacement during functional forces. Rounded internal line angles and a 90 degree cavosurface margin can contribute to optimal resistance form. Option A is incorrect because while converging internal line angles may aid in retention, they can weaken the structure and compromise resistance form. Option C is incorrect because while parallel walls may aid in resistance form, a 90 degree cavosurface margin is not ideal as it can create stress concentration and lead to failure. Option D is incorrect because undercuts may aid in retention, but they can also increase the risk of fracture and do not contribute to resistance form.