Chapter 20: Bisecting Technique

These flashcards cover key concepts and steps related to the bisecting technique in dental imaging, including receptor placement, angles, and exposure sequences.

What is the bisecting technique in dental imaging?

A method used to expose periapical images by positioning a receptor along the lingual surface of the tooth and utilizing angulation.

What is the angle bisector in the bisecting technique?

An imaginary line that bisects the angle formed by the receptor and the long axis of the tooth.

What is the importance of the rule of isometry in the bisecting technique?

It states that two triangles are equal if they have two equal angles and share a common side, which applies to forming equal triangles in dental imaging.

What are the steps of the bisecting technique?

1. Receptor placement 2. Receptor position 3. Vertical angulation 4. Horizontal angulation 5. Receptor exposure.

What type of triangles are formed in the bisecting technique?

Right triangles that are congruent.

What are the common receptor holders used during the bisecting technique?

Stabe Bite-block and Rinn Snap-A-Ray Holder.

How is horizontal angulation defined?

The positioning of the tubehead and direction of the central ray in a side-to-side plane.

What is correct horizontal angulation?

The central ray is directed perpendicular to the curvature of the arch through the contact areas of the teeth.

What results from incorrect horizontal angulation?

Overlapped contact areas.

What is vertical angulation?

The positioning of the PID in a vertical or up-and-down plane.

What is correct vertical angulation?

It results in a radiographic image that is the same length as the tooth.

What leads to foreshortened images in radiography?

Excessive vertical angulation.

What leads to elongated images in radiography?

Insufficient vertical angulation.

What receptor size is traditionally used for the bisecting technique when imaging anterior teeth?

Size 2 receptor, placed vertically.

What receptor size is traditionally used for the bisecting technique when imaging posterior teeth?

Size 2 receptor, placed horizontally.

What is the first step in the anterior exposure sequence?

Begin with the maxillary right canine tooth.

What is the last step in the anterior exposure sequence?

End with the maxillary left canine.

What is the first step in the mandibular exposure sequence?

Begin with the mandibular left canine.

What is the last step in the mandibular exposure sequence?

Finish with the mandibular right canine.

What is the first quadrant to expose in the posterior exposure sequence?

Begin with the maxillary right quadrant.

What is the order of quadrants in the posterior exposure sequence?

Maxillary right, mandibular right, maxillary left, mandibular left.

What should be exposed first in each quadrant during the posterior sequence?

The premolar receptor should be exposed before the molar receptor.

What is an advantage of the bisecting technique?

It can be used without a beam alignment device.

What is a disadvantage of the bisecting technique?

It can result in image distortion.

What can cause angulation problems in the bisecting technique?

Incorrect vertical or horizontal angulation.

What must be done to the treatment area before patient exposure?

Infection control procedures and preparation of treatment area and supplies.

What is essential for patient preparation in the bisecting technique?

The patient is seated and prepared for exposure.

What is the requirement for the central ray in relation to the imaginary bisector?

The central ray must be directed perpendicular to the imaginary bisector.

What should be the position of the receptor during the bisecting technique?

The receptor must be placed along the lingual surface of the tooth.

What determines the success of posterior radiographic images?

Correct angulation of the central ray.

What is a significant factor to avoid when taking radiographs?

Overlapping contact areas due to incorrect horizontal angulation.

What does patient positioning affect in the bisecting technique?

The quality and accuracy of the radiographic images.

What basic geometric principle is applied in the bisecting technique?

The rule of isometry, relating to equal angles and shared sides in triangles.