X-Ray Study Guide 1

Why do we take x-rays?

help save lives and money

What is the order of solutions in processing film?

1.developer

2.fixer

3.water

What causes forshortening?

-processing

-placement error

Snap of ray are ___ ended, used for bi-section.

double

Why are x-rays important?

-diagnose caries

-evaluate health of tooth and bone

-evaluation of growth and development

What type of people do we use occlusal film for?

children and edentulous pts.

What might we find out on an x-ray?

Find abscesses, tumor, extra teeth, caries

What does ionization causes?

causes harmful effects in humans

Important property of x-rays:

shorter wavelengths are preferred

What is the basic aim of the use of radiation?

Obtain the desired diagnostic info with minimal exposure to the pt. and dental team

How can we protect ourselves and our patients?

staying away 6ft., eliminating contrast by adjusting equipment

What can we NEVER do while taking x-rays?

holding the cone or not standing behind the lead/gypsum wall

What is the primary measurement of operator x-ray exposure called?

REMs (Roentgen Equivalent Man)

How do we measure radiation absorbed?

RAD (Radiation Absorbed Dose)

How can we filter the x-ray beam?

use of an aluminum filter

What do we do if a patient refuses x-rays?

That the patient might not get the care they need if they deny help from the dentist. X-Ray refusal form! (most important)

What is a latent period in radiation biology?

(stimulus to effects)

What is a latent period anywhere else?

period between infection with a virus or other microorganisms and the onset symptoms

(time in between)

What is the best film speed?

F (fast)

Why is "F” the best film speed?

it is the fastest and it absorbs radiation the quickest

What are examples of processing errors?

-temp. of solution

-light exposure

-stored poorly in container

-time exposed to chemicals

What is the lead washer and what is its function?

It helps limit the size of the radiation beam

What causes scatter radiation?

Radiation that bounces off objects and the pt. (target)

What does ALARA stand for?

As Low As Reasonably Achievable

What is the point of ALARA?

to obtain the desired diagnostic information with minimum exposure to the patient and dental personnel

What did we learn about processing x-rays?

minimize the amount of retakes, be able to see contact points, see different color indications, and always maintain diagnostic quality

(70 degrees in five minutes)

What is the greatest danger to the operator in terms of radiation encountered in the dental office?

scatter radiation!

Name a few examples of cells that are more vulnerable to radiation.

Blood cells, immature reproductive cells, young bone cells, lymphoid tissue, bone marrow, testes, and intestines

What are the different types of effects of radiation on cells?

Short term and long term effects, somatic and genetic

What cells are more reactive?

thyroid cells, blood cells, reproductive cells, bone marrow

What cells are less reactive?

muscles, salivary glands, kidney cells, mature blood cells

What are the responsibilities of x-ray unit owners?

-registration of dental radiographic equipment

-radiation protection

-every 2 years you need to re-register

-make sure it's in safe working order (no leaks)

What is title 17 in the CA radiation handbook about?

-registering their x-ray machines

-up to date on the registration at least 30 days after having it in their possession

-renew it every two years

-when getting rid of it, register that you no longer have it

What factors affect the amount of radiation present during the x-ray Process?

The film speed, modifying setting, speed, time, distance traveled, density

How much radiation should a dental assistant be occupationally exposed to?

0%

How will you monitor radiation a dental assistant could be occupationally exposed to?

dosimeter badge

Why are different materials different shades on an x-ray?

Bone density (atomic number)

What is the best protection from radiation for an operator?

standing behind a lead/gypsum wall

In your own words, how are x-rays made?

filament heats, boils electrons, negative and positive electrons, collision, energy created, shoots out PID

What is the collimator?

…

What is the collimator also called?

lead washer

What is the function of a collimator?

restricts the size of a primary beam to a maximum of 2.75 inches

What would you say to a patient who asked why you leave the room when x-rays are taken?

you are here to take your x-rays and I am here taking them every day so my exposure is a lot more than yours

(your exposure is a lot less than mine)

What would you say to a patient who declines x-rays?

X-rays are very important to find out things we may not see. If pt. still refuses, have them fill out X-ray Refusal Form.

X-ray tube:

allows x-rays to pass through

Metal housing:

keeps radiation inside

Insulating oil:

absorbs any heat or energy

Glass window:

Allows radiation through

Lead collimator:

Restricts size of beam of 2.75 inches

PID/Cone:

Directs the beam to the target

Aluminum disc:

Filters radiation

Tube head seal:

Seals everything off

Filament circuit:

Heats up electrons

Cathode:

Produces electrons (negative)

Anode:

creates positive charge

What is the latent period in radiograph?

period in between exposure and effect

What are the key differences between somatic and genetic effects of radiation? Somatic:

any cell but reproductive cells (occurs in person who was exposed)

What are the key differences between somatic and genetic effects of radiation? Genetic:

damage to genetic cells or chromosomes, may appear in future generations, and can't be repaired

Where would we find specifics about the safe use of dental radiation?

CA Radiation handbook

Can the assistant diagnose radiographs?

No, only dentists may (DA can only interpret/take)

What are examples of extraoral films?

-CBCT 3D

-Panoramic

-Ceph. 2D

What are examples of intraoral films?

-PA

-BW 2D

-occlusal

What is the difference between intraoral and extraoral films?

one is taken inside the mouth and the other is outside of the mouth

How would we identify the sinus on a radiograph?

show as radiolucent AKA dark

Where is the sinus found on a radiograph?

maxillary/posterior arch above the roots of the teeth

What does the sinus look like?

dark spaces

What does periapical/PA mean?

around the root (a few mm under the root)

What is expected to be seen in a PA?

shows the entire tooth and surrounding structures

What is film size 0 used for?

pedo.

What is film size 1 used for?

ant. PA

What is film size 2 used for?

post. PA, BW AKA adult film

What is film size 3 used for?

long BW

What is film size 4 used for?

occlusal

What is the measurement “rad” for?

measuring how much radiation the DA has taken in

Why are different structures/objects different shades on a radiograph?

The densities determine whether or not they are radiopaque or radiolucent

What will we find on a Panoramic radiograph?

the entire jaw, unerupted teeth, 3rd molars, impacted teeth, nerve, and TMJ

Can any exposure to radiation potentially cause damage?

Yes, there is potential short-term damage and long-term damage along with somatic and genetic effects

What controls the quantity of an x-ray beam?

MA

What controls the quality of an x-ray beam?

KVP

What controls the intensity of an x-ray beam?

exposure, time, distance, KVP, MA (all of the above)

What is required for duplicating film?

-dup. film

-dup. machine

-dark room

Why would we duplicate film?

1) referring a pt. to a specialist

2) sending copies to ins. company

3) when a pt. requests records transfer

What is an intensifying screen for?

For extraoral films like Pano. and Ceph.

Why is the intensifying screen beneficial?

-limiting radiation

-intensifies effects of radiation

What receptacle holder is used for parallel technique?

XCP

What receptacle holder is used for bisection technique?

snap of ray

What is used for extraoral radiography (receptacle)?

cassette

What does the color yellow represent for a receptacle holder?

post. PA

What does the color blue represent for a receptacle holder?

ant. PA

What does the color red represent for a receptacle holder?

BW

What is meant by radiolucent?

dark on x-ray

What is meant by radiopaque?

light on x-ray

What is an example of a radiolucent?

abscess

What is an example of a radiopaque?

amalgam filling (mostly all restorations)

What is ideal contrast and how is it controlled?

High KVP = low contrast

&

long color scale

How could we tell if the x-ray holder is for digital or traditional film?

gap of space on a snap ray

and

there’s a digital sensor

What do we know about the “dot” on the x-ray? Where should that always face?

faces yourself

PA = occlusal area

BW = facing towards us, bottom right

How thick must the aluminum filter be on an x-ray unit that operates over 70 KVP?

2.5 mm

Can any exposure to radiation potentially cause damage?

YES