X-Ray Film, Equipment: Ch. 6 & 7

What is the purpose of Gelatin & Halide Crystals in Film Emulsion?

Gelatin: disperses silver halide crystals over film base. Halide Crystals: absorb radiation during exposure & store the energy.

What adversely effects Films?

Heat, Humidity, & Radiation.

Extraoral Film: Intensifying Screens / Cassetes

Intensifying Screens: Device that transfers energy into visible light. The light exposes the screen film. Lowers radiation dose. The screen film is secured in a cassette.

What are the 3 types of Dental X-Ray Film?

Intraoral Extraoral Duplicating

Film Base

.2 mm thick piece of polyester plastic. Provides strength & stable support for the delicate emulsion.

What are Film Sizes?

0, 1, 2, 3, 4

Film Size: Bite-Wing

0: Post. / Small Kids 2: Post. / Older Kids & Adults 3: Longer & Narrower than Standard #2. Used only for Bite-Wing. (Not recommended. All contacts can't be opened on 1 film.) Shows all posteriors on 1 side in 1 film.

Film Size: Periapical

0: Small kids 1: Ant. / Adults 2: Standard. Ant. & Post. / Adults

What is the raised Identification Dot for on an intraoral film packet?

1. To determine film ORIENTATION 2. Distinguishing R & L 3. Helps with MOUNTING *Is on TUBE SIDE of the film packet. If it is reversed, the foil sheet will be in front of the film creating a Reversed Film & Underexposure

What information would be found on a Film Packet?

1. Type of Film 2. Speed 3. Size 4. # / Packet 5. # Total 6. Expiration Date

What year did they begin having federal standards for dental X-ray machines?

1974

Film Size: Occlusal

4: To examine large areas of the Max. or Mand. (Almost 4x the size of standard #2)

What is the best Temp. for Film Storage?

50-70*F

When using a portable x-ray device, what limits operator exposure?

A lead acrylic disk shield around the PID

Occlusal Film

A survey film that shows the entire upper and lower arch. Larger. Patient "Occludes" on the entire film. #4 for Adults, #2 for Kids.

How does Dental x-ray Film work to create an image?

A type of photographic film adapted for dental use. An image is produced on dental x-ray film when it is exposed to radiation that has passed through teeth & adjacent structures. The film serves as an IMAGE RECEPTOR (picture; responding to stimulus)

What is the range of Film Speeds?

A-F. A = Slowest, F = Fastest. Only D through F films are used for intraoral. Slow: Sharper, Smaller Crystals, More Exposure Fast: Less sharp, Larger Crystals, Less Exposure

Adhesive Layer

Adhesive on both sides of film base. Attaches Emulsion in place.

Bite-Wing Film

Examines crowns of Max & Mand on 1 Film Used to examine Interproximal Can use stick on tabs & patient "Bites" to stabilize. #2 for Adults.

What are the 4 basic components of X-Ray Film?

Film Base Adhesive Layer Film Emulsion Protective Layer

Film Storage & Protection

Film is negatively effected by: Heat, Humidity, & Radiation. Should be kept in a cool, dry place. HAS an expiration date.

Periapical Film

Film that shows the entire tooth & supporting bone. Peri = Around, Apical = Apex of Root. Should show 1-3mm above apex & 1mm below crown. Need to be taken using an xCP to line up. Use #1 for Ant. & #2 for Post.

Are portable dental X-ray units approved in all states?

No

What is the purpose of the Lead Foil in the film packet?

To shield the film from backscattered radiation resulting in film fog.

Outer Film Package Wrapping: Label Side & Tube Side

Tube Side: Solid WHITE. ID dot. This surface must face the TEETH & the TUBEHEAD. "White in Sight" Label Side: Flap. Colored. Must face the TONGUE. Information printed on this side: ID dot, "Opposite side toward tube", Manufacturer, Speed, # of Films enclosed.

What are the 3 components of X-ray machines?

Tube head Extension Arm Control Panel

Extraoral Film

Used to examine large areas of the head or jaw Panoramic: Wide view of upper & lower jaws Cephalometric: Bony & Soft Tissue areas in Profile (From side-to-side)

Protective Layer

thin, transparent coating over emulsion, protects surface from damage. *The outermost Layer. If this were a sandwich, this would be the 🍞

ALARA

As Low As Reasonably Accepted

What instrument is used to help position the PID in relation to the tooth and receptor?

Beam Alignment Device

Calcium Tungstate Screens & Rare Earth Screens

CTS = Blue Light RES = Green Light

Film Emulsion

Coating on both sides of film base by the adhesive layer to make X-radiation more sensitive. Mix of Gelatin & Silver Halide Crystals

What device is used to restrict the size of an X-ray beam to the size of a receptor?

Collimating Device

Do you need 2 separate exposures for the Duplicating Film?

No. 2 films are taken at the same time (creating an identical duplicate) with the same exposure it takes to take 1. *TWINS!

Are Portable Intraoral units approved by ALL states?

No. Although they have recently been approved for dentistry by the FDA & have been known to produce high-quality, diagnostic images, each state radiation control board determines the use.

What does the Control Panel consist of?

On/Off switch & Indicator Light Exposure Button & Exposure Light Control Device for Time Control for Kilovoltage/miliamperage

What are 3 INTRAORAL Film Types?

Periapical Bite-Wing Occlusal

PID

Positioning Indicating Device

What is the device used to stabilize an intraoral receptor?

Receptor Holder

The State & Local Gov

Regulates how Equipment is used *They are closer, so can better supervise use

The Federal Government

Regulates manufacture & install of X-ray equipment

Extraoral Film: Screen / Nonscreen

Screen: Requires screen in a cassette w/ phosphors for exposure. Screen in sensitive to fluorescent light rather than direct X-Radiation. Non-Screen: Doesn't require screen. Exposed directly to x-ray. NOT recommended for dental use.

Radiation to Dense Surfaces (bone) vs. Air Space

Silver Halide Crystals positioned behind a dense object like Bone or Amalgam restorations receive little to no radiation because of the density of the object (it absorbs the radiation rather than the halide). The objects appear Radio-opaque or White. The Halide Crystals are not energized. When the x-ray beam goes through airspace, the Halide Crystals receive more radiation, charging them. This produces a dark, or black surface because the Halide soaked up the radiation rather than going through an object with density and therefore creating an image.

Types of receptor holders

Styrofoam Bite Block Snap-A-Ray EndoRay Uni-bite

Film Speed: What effects it?

The amount of radiation requires to produce radiograph of standard density. -Size of Halide Crystals -Thickness of Emulsion -Presence of special radiosensitive dyes Fast = Less radiation exposure

What are the 4 components of film packets?

X-Ray Film Paper Film Wrapper Lead Foil Sheet Outer Package Wrapping

Latent Image

invisible image created after exposure but before processing. Cannot be seen until chemical processing to produce a visible image.