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

Bite-wing technique

Used to examine interproximal surfaces of teeth; useful to monitor the progression of dental caries, assess existing restoration, and examine the crestal bone levels

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

mA, kVp, exposure time

In density increases the image becomes ____

darker

If subject thickness increases, density ____

descreases

Contrast

difference between dark and light areas on the image

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

contrast

difference between dark and light areas on the image

kVp controls the _____ of the x-ray beam and therefore affects contrast (kontrast)

quality

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

many shades of gray (low contrast) long scale

Low kVp

mostly black and white (high contrast) short scale

using a longer PID _____ magnification

reduces

Bite-wing beam alignment device (XCP)

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

Correct horizontal angulation

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

Incorrect horizontal angulation

Incorrect horizontal angulation is always the
reason for overlapped contact areas!!!

Vertical Bite-Wings

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

Types of Intraoral Imaging Examinations

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

Purpose of periapical examination

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

_____ technique is preferred using the XCP

paralleling

Interproximal examination purpose

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

Interproximal examination technique

bite-wing (interproximal exam)

occlusal examination purpose

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

technique used for occlusal examination

occlusal (sandwhich bite)