click below
click below
Normal Size Small Size show me how
Radiology
Chapter 7 & 8
Term | Definition |
---|---|
Duplicating film | A photographic film similar to x-ray film. Exposed by the action of infrared and ultraviolet light rather than by x-rays. |
Emulsion | The gelatinous coating on radiographic film containing silver halide crystals. |
Halide | A compound of a halogen with another element or radical. |
Intensifying Screen | Plastic sheet coated with calcium tungstate or rare earth fluorescent salt crystals. Salts glow when exposed to radiation, giving off a blue or green energy of each x-ray. |
Occlusal Radiograph | Radiograph produced by placing film against the incisal or occlusal plane. Stabilizes by biting down. |
Pedodontic Film | Size No. 0 film. Designed for small children |
Silver Halide Crystals | Sensitive to radiation and when exposed to x-rays, they retain the latent image. |
Latent Image | The invisible image produced when the film is exposed to x-ray photons. Image remains invisible until the film is processed. |
Acidifer | A chemical (acetic acid) in the fixer solution that neutralizes the alkali in the developer solution and stops further action of the developer. |
Developing Agent | Elon and hydroquinone, substances that reduce the halides in the film emulsion to metallic silver. Elon brings out the details, and hydroquinone brings out the contrast in the film. |
Selective Reduction | Chemical change that takes place within the film emulsion during development. During this change, the nonmetallic are separated from the silver halide, leaving a coating of metallic silver on the film emulsion while the bromide is removed. |
Identification Dot | Small circular embossed mark on the corner of intraoral x-ray film. Used to determine the patient's right or left side when viewing radiographs. |
Latent Image | A chemical (acetic acid) in the fixer solution that neutralizes the alkali in the developer solution and stops further action of the developer. |
Fixing Agent | Sodium thiosulfate, also known as "hypo" or hyposulfite of sodium. It is one of several chemical ingredients in the fixer solution and functions to remove all unexposed and any remaining undeveloped silver bromide grains from the emulsion. |
Automatic Processor | Converts the invisible latent image on the dental x-ray film into a visible permanent image. |
Oxidation | The process during which the chemicals of the developing and fixing solutions combine with oxygen and lose their strength. |
Safelight | Special filtered light that can be left on in the darkroom while films are processed. |
Which of these provides support for the fragile film emulsion? a. Base b. Adhesive c. Gelatin d. Silver Halide Crystals | a. Base |
Which of these is light and x-ray sensitive? a. Lead Foil b.Adhesive c.Gelatin d.Silver Halide Crystals | d. Silver halide crystals |
During x-ray exposure, crystals within the film emulsion become energized with a(n) a.visible image b.slow image c.latent image d.intensified image | c. latent image |
What is the function of the lead foil in the film packet? a.moisture protection b.absorb backscatter radiation c.give rigidity to the packet d.protect against flourescence | b. absorb backscatter radiation |
Each of the following can be found on the back side of an intraoral film packet EXCEPT one. Which one is the EXCEPTION? a.film speed b.film size c.embossed dot location d.number of films in packet | b. film size |
Which of these films has the greatest sensitivity to radiation? a. D-speed b. E-speed c. F-speed | C. F-speed |
A size #4 intraoral film packet would most likely be used to expose a(n) a.bitewing radiograph b.periapical radiograph c.occlusal radiograph d.panoramic radiograph | c. occlusal radiograph |
Which of these projections will the dentist most likely prescribe for evaluation of a specific tooth and its surrounding structures? a. bitewing radiograph b.periapical radiograph c.occlusal radiograph d.panoramic radiograph | b. periapical radiograph |
Intensifying screens will a. reduce exposure time b. decrease processing time c. increase x-ray intensity d. increase image detail | a. reduce exposure time |
Which of the following is considered to be a screen film? a.Occlusal b.periapical c.bitewing d.panoramic | d. panoramic |
Which type of film is used to cody a radiograph? a.duplicating film b.screen film c.nonscreen film d.x-ray film | a. duplicating film |
X-ray films sould be stored a.away from heat and humidity b.near the source of radiation c.in the darkroom d.stacked in columns | a. away from heat and humidity |
Which term best describes the process by which the latent image becomes visibe? a.reticulation b.reduction c.activation d.preservation | b. reduction |
Which of these is the correct processing sequence? a. rinse, fix, wash, develop, dry b.fix, rinse, develop, wash, dry c.develop, rinse, fix, wash, dry d.rinse, develop, wash, fix, dry | c. develop, rinse, fix, wash, dry |
The basic constituents of the developer sloution are; a.reducing agent, activatior, preservative,restrainer;c.clearing agent, activator, preservative,restrainer; d.clearing agent, preservative, hardener, acidifer | a. reducing agent, activator, preservative, restrainer |
During which step of the processing procedure are the exposed silver halide crystals reduced to metallic silver? a. developing b. fixing c. rinsing d. washing | a. developing |
Which ingredient removes the unexposed/undeveloped silver halide crystals from the film emulsion? a. acetic acid b. potassium bromide c. sodium thiosulfate d. hydroquinone | c. sodium thiosulfate |
Which ingredient causes the emulsion to soften and swell? a. acidifier b. preservative c. restrainer d. activator | d. activator |
Which ingredient hardens the emulsion? a. elon b. potassium alum c. sodium carbonate d. sodium sulfite | b. potassium alum |
Chemically, the developer used in an automatic processor contains more___________than developer used for manual processing. a. activator b. acid c. preservative d. hardener | d. hardener |
Each of the following should be considered when setting up an ideal darkroom EXCEPT one. Which one is the EXCEPTION? a. Black walls b. location c. lighting d. size | a. black walls |
Which of the following colors or safelight filters is safe for processing all film speeds? a. yellow b.green c.red d. blue | c. red |
What is the minimum safe distance to position the safe-light abouve the work area in the darkroom? a. 2 ft (0.6m) b. 4 ft (1.2m) c. 6 ft (1.8m) d. 8 ft (2.4m) | b. 4ft (1.2m) |
What is the appearance of the radiographic image if a film is exposed to a safelight too long? a. oxidized b. fogged c. fixed d. attenuated | b. fogged |
Which of these is considered a disadvantage of manual processing over automatic processing? a. darkroom required b. processing time is long c. chemicals must be replinished d. temperature must be regulated | b. processing time is long |
A thermometer is used for manual processing to determine the temperature of the a. developer solution b. water c. fixer solution d. both a and c | a. developer solution |
Each of the following is necessary and required for manual processing EXCEPT one. Which one is the EXCEPTION? a. Thermometer b. Timer c. Film dryer d. frilm hanger | c. film hanger |
What is the ideal temperature for processing film manually? a. 60 F (15.5 C) b. 68 F (20 C) c. 75 F (23.9 C) d. 83 F (28.3 C) | b. 68 F ( 20 C) |
A film may be safely exposed to white light for a wet reading after two or three minutes of a. developing b. rinsing c. fixing d. washing | c. fixing |
Each of the following is true regarding rapid film processing EXCEPT one. Which one is the EXCEPTION? a. uses a miniature darkroom placed on the counter in the operatory. b. produces archival (permanent) quality radiographs c. developer heated to high | b. produces archival (permanent) quality radiograph |
Each of the following is an advantage of automatic processing over manual processing EXCEPT one. Which one is the EXCEPTION? a. less maintenance b. decreased processing time c. increased capacity for processing d. self-regulation of time and temp. | a. less maintenance |
Replenisher is added to the developing solution to compensate for a. oxidation b. loss of volume c. loss of solution strength d. all of the above | d. all the above |
Which processing method requires the most maintenance and the strictest adherence to regular replinishment and cleaning? a. manual b. rapid c. automatic | c. automatic |