Radiology test 2

What are the basic principles to taking proper occlusal radiographs?

-Position the film with the white side facing arch being exposed

-Place the film in mouth between occlusal surfaces of arches

-Film will be stabilized when client bites down gently on film

What are the appropriate film sizes to use for occlusal radiography?

Size 4 for adult, but size 2 can be used for primary dentition

What is a maxillary topographic occlusal projection? Describe its properties

A shot that examines palate and maxillary anterior teeth

-max arch will be positioned parallel to floor

-central ray directed to midline of arch

-65 degree vertical angulation

-portal of entry - top edge of PID between client’s eyebrows and bridge of nose

What is a maxillary Lateral Projection? Describe its properties

A shot that examines palatal roots of molar teeth or to examine posterior maxilla

-max arch will be positioned parallel to the floor

-film shifted to side of interest

-60 degree vertical angulation

-portal of entry - top edge of PID above corner of eyebrow, directed to area of interest

What is a pediatric projection? Describe its properties

Used to examine the anterior teeth of maxilla for children 5 years old or younger

-uses size 2 film

-60 degree vertical angulation

-Portal of entry - top edge between eyebrows on bridge of nose

What is a mandibular topographic occlusal projection? What are its properties?

A shot that looks at the anterior teeth of the mandible

• -55 degrees at the chin

What is a mandibular corss sectional occlusal projection?

Client reclines to have the arch face perpendicular to the floor

-uses size 4 film

-PID apx 1inch below client’s chin

What is a mandibular pediatric occlusal projection? describe its properties

For viewing the mindibular anterior teeth of a child

• -55 degrees vertical angulation and PID over child’s chin

Describe the localization technique

For locating the position of an object or tooth in the jaws. Obtains 3 dimensional information despite a radiograph being a 2 dimensional image.

Able to locate foreign bodies, impacted/unerupted teeth, root positions, salivary stones, jaw fractures, broken needles and instruments and filling materials

Briefly describe the buccal object rule

also called “SLOB” (same lingual, opposite buccal)

Take two radiographs, one regular and one slightly shifted. If object moves in same direction as tubehead, it is lingual. If it moves in opposite direction, its buccal.

What is the buccal object rule for localization

Determines the position of a tooth treated endodontically with gutta percha in a maxillary second premolar

What are the different types of extra oral radiographs

Panoramic, lateral jaw projection (replaced by pans but more detailed), cephalometric (head. lateral skull for facial growth and development, posterioanterior for frontal and ethmoid sinuses) and water’s (sinuses)

What are panoramic radiographs? why use?

an extra oral radiograph to view the maxilla, mandible, tmj, teeth and supporting structures.

see inpacted teeth, eruption patterns, detect diseases and conditions, evaluate trauma and examine large lesions

How should you set up the client before taking the radiograph?

-remove metals, hearing aids and removable mouth stuff

-stand “as tall as possible” (white shadow comes over image if spine not straight)

-client bites on plastic block with tongue on roof of mouth, midsagital plane perpendicular to floor, head straight (prevents distortion)

-frankfort plane (top of ear to bottom of eye socket) parallel to floor

What are some advantages and disadvantages of panos?

-adv: large field size (can view a lot), simple to use, very comfortable for patient, minimal rad exposure

-dis: Lower image quality than conv IO film (can’t look at caries, perio disease, lesions), limited focal view, always creates some sort of distortion, very expensive to purchase.

How can you manage paedo clients during radiography

-explain the procedure in ways a child will understand

-ensure they use a lead apron

-reduce exposure factors (mA, KV, time)

-use a 0 size receptor (mixed can use 1 or 2)

How can you place a film in someone with a rubber dam

use an EndoRay film holder (fits around clamp) with paralleling technique.

Describe the different types of caries you can see on a radiograph

moderate occlusal caries - thin radiolucent line on dentin, enamel remains same

severe occlusal caries - large radiolucency. more apparent clinically

buccal and lingual caries - lesion appears as small circular area (more apparent clinically)

interproximal caries - radiolucent triangle shape at or just below contact point