California Registered Dental Assistant (RDA) Written Practice Exam

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

Prepare effectively for the California Registered Dental Assistant (RDA) Written Exam. Utilize our comprehensive quizzes and resources, featuring multiple-choice questions that enhance your understanding and readiness for the exam!

Practice this question and more.

What is a 'smile line'?

The curve of the lips
The outline of the mouth
The portion of the teeth shown when a patient smiles
The alignment of the teeth

The correct answer is: The portion of the teeth shown when a patient smiles

A 'smile line' refers to the portion of the teeth that is visible when a person smiles. This includes both the upper and lower teeth and is typically used as an aesthetic measurement in dentistry. Option A, the curve of the lips, may contribute to the appearance of a smile line, but it is not the same thing. Option B, the outline of the mouth, does not specifically refer to teeth and therefore is not a complete definition of a smile line. Option D, alignment of the teeth, is a factor that can affect the appearance of a smile line, but it is not the definition of a smile line. Only option C accurately defines a smile line.