National Dental Assisting Examining Board (NDAEB) Practice Exam

What do we call an angle formed by the junction of three surfaces at one point?

1. Point Angle

2. Vertex Angle

3. Dihedral Angle

4. Acute Angle

The correct answer is: Point Angle

The term for the angle formed by the junction of three surfaces at one point is known as a point angle. In dental anatomy, point angles are particularly relevant because they help in understanding the configuration of dental restorations and tooth preparations. A point angle is effectively where three planes intersect, creating a specific angular relationship that is critical to the design and functionality of dental work. Understanding this definition can aid in visualizing how three-dimensional aspects of dental structures are represented in dentistry. This concept is especially useful in fields such as orthodontics, restorative dentistry, and oral surgery, where precise angles are crucial for the success of clinical procedures and optimal outcomes. Other terms highlighted in the choices have distinct meanings: a vertex angle pertains to angles formed at the vertex of a triangle, a dihedral angle is the angle between two intersecting planes, and an acute angle is a generic term for any angle less than 90 degrees. These terms do not apply to the specific configuration of three surfaces meeting at a single point, thereby reinforcing the unique nature of a point angle in dental practices.