module 3 Rad

What is a stepwedge composed of?

Aluminum

What does high contrast in a dental image indicate?

Very dark and very light areas

What is magnification in dental imaging?

An image that appears larger than its actual size

How can a radiographer compensate for magnification due to IR placement?

Use a longer PID

What does radiopaque refer to in a dental image?

Portion that appears light or white

What dental materials appear the most radiopaque?

Metals

What does radiolucent refer to in a dental image?

Portion that is dark or black

What part of the tooth appears the most radiolucent?

Pulp (decay, cysts, etc.)

What factors can increase density in a dental image?

mA, time, and kVp

What is density in the context of dental imaging?

Overall blackness or darkness of an image

What effect does an increase in subject thickness have on image density?

Results in less density

What is contrast in a dental image?

Difference in degrees of blackness between adjacent areas

Which exposure factor controls contrast on an image?

kVp (kilovoltage)

What is distortion in dental imaging?

Variation in true size and shape of the object

What is sharpness in dental imaging?

Capability of the receptor to reproduce distinct outlines of an object

What factors can improve the sharpness of an image?

Small focal spot, no movement, small crystal size (more pixels)

How can dimensional distortion be minimized?

By placing the PID perpendicular to the tooth and receptor, and the receptor parallel to the tooth

How frequently should you take a full mouth series (FMX) on a patient with no clinical signs of disease?

Every 3-5 years

What is a panoramic image?

An example of an extraoral technique for a dental image examination

How many dental images are typically taken for a full mouth series?

18 in our clinic (14-20)

What is the purpose of a periapical image?

To evaluate the crown, roots, and supporting bone of a tooth

What does a bitewing image evaluate?

Interproximal areas of the crowns of both maxillary and mandibular teeth

What type of examination evaluates the maxillary or mandibular arch in one intraoral image?

Occlusal examination

What does the term 'occlude' mean in dentistry?

To close or bite down

Which techniques can be used for periapical images?

Paralleling technique (preferred) or bisecting technique

Where should the mesial edge of the IR be placed for a molar bitewing image?

At the midline of the 2nd mandibular premolar

What receptor size is recommended for an adult bitewing?

Size 2

When should adult bitewings be taken vertically?

For perio patients

What is recommended for patients with a sensitive gag reflex?

Take anterior images first, then complete posterior periapicals and bitewings

What causes overlapped IP contacts?

Improper horizontal angulation

Where should the mesial edge of the IR be placed for a premolar bitewing image?

At the midline of the mandibular canine

What size receptor should be used for a pedodontics patient?

Size 0

How can a radiographer stabilize the receptor in an edentulous area when taking bitewings?

Use a cotton roll

The bite-wing technique is also known as the?

interproximal technique

What causes overlapped contacts?

Incorrect horizontal angulation

IR is placed in the mouth _ to the crowns of both the upper/lower teeth.

parallel

Central ray is directed through the contacts of the teeth at what angulation for bitewing technique?

+10 vertical due to the curve of Spee

Factors that increase density include?

mA, kVp, exposure time

In density increases the image becomes ____?

darker

If subject thickness increases, density ____?

decreases

What controls contrast?

kVp

Decreasing exposure time makes the image ___?

lighter

Decreasing mA makes the image ____?

lighter

Increasing exposure time makes the image ___?

darker

Increasing subject thickness = ____ ____?

less density

What controls the quality of the x-ray beam and therefore affects contrast?

kVp

High kVp = _ contrast?

low; many shades of gray

Low kVp = ___ contrast?

high; mostly black and white

Magnification increases when the object is ____ away from the receptor?

farther

High kVp indicates?

many shades of gray (low contrast) long scale

Low kVp indicates?

mostly black and white (high contrast) short scale

Using a longer PID _ magnification?

reduces

What is the purpose of the Bite-wing beam alignment device (XCP)?

Used to position an IR in the mouth and maintain its position during the procedure

What is the correct horizontal angulation for the central ray?

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

What is the reason for overlapped contact areas?

Incorrect horizontal angulation is always the reason!

What are Vertical Bite-Wings used for?

Used to examine the level of alveolar bone; should be performed on all periodontal patients!

What Types of Intraoral Imaging Examinations are there?

Periapical (PA) examination, Interproximal (BWX) examination, Occlusal examination

What is the purpose of the periapical examination?

Examines the entire tooth (crown to root) and supporting bone (2-3 mm preferred)

Which technique is preferred using the XCP?

Paralleling technique

What is the Interproximal examination purpose?

Examines crowns only of maxillary and mandibular teeth on a single film

What technique is used for interproximal examination?

Bite-wing (interproximal exam)

What is the purpose of the occlusal examination?

Examines large areas of the maxilla or the mandible on one film

What technique is used for occlusal examination?

Occlusal (sandwich bite)