INBDE (Integrated National Board Dental Examination) Practice Exam

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Prepare for the INBDE (Integrated National Board Dental Examination) exam. Study with flashcards and multiple choice questions, each with hints and explanations. Get ready for your exam!

Practice this question and more.

In what direction do wrinkles form in relation to muscle pull?

Parallel
Perpendicular
Random
Diagonal

The correct answer is: Perpendicular

Wrinkles form perpendicular to muscle pull because of the way the muscle fibers orient themselves. When the muscle contracts, the fibers pull together, which causes a perpendicular wrinkling effect on the skin. This is why options A, C, and D are incorrect. Wrinkles formed in parallel with muscle pull would require the muscle fibers to be aligned in a way that does not occur naturally. Random wrinkles suggest no correlation with muscle pull at all. Diagonal wrinkles may occur, but not consistently, making option D incorrect.