NBDHE: Oral and maxillofacial radiology

Which item remains stationary during panoramic exposure? a. patient b. film c. tubehead d. cassette

A. The patient patient needs to remain still during panoramic exposures.

What is primary factor in the determination of the contrast of an image a. kVp b. Exposure time c. source-to-receptor distance d. mA

A. kVp The only factor that has a direct influence on the contrast of a radiographic image is kVp.

Which is an appropriate condition to expose a periapical radiograph? a. Pulpitis b. slight bone loss c. Amalgam overhang d. Interproximal caries

A. pulpitis purpose of a periapical radiograph is to examine the entire tooth and surrounding bone, including the terminal end of a tooth root, a likely location of pulpitis.

Which statement is correct for the production of the most diagnositc image? a. the receptor is placed as close as possible to the tooth b. the shortest PID length is used c. the receptor is placed as far away from the tooth as possible d. the x-ray beam is positioned parallel to the long axis of the tooth

A. the receptor is placed as close as possible to the tooth To limit magnification and create a diagnostic image, the tooth and receptor should always be placed as close together as possible.

In what part of the x-ray tube does the thermionic emissions occur a. positive anode b. positive cathode c. negative anode d. negative cathode

D. Negative cathode Thermionic emission is the release of electrons from the tungsten filament of the negatively charged cathode.

A person standing 2 ft. from a source of radiation receives a dose of 2 rad. what would be the dose for a person standing 4 ft. from source of radiation? a. 0.5 rad b. 1.0 rad c. 2.0 rad d. 4.0 rad

a. 0.5 rad inverse square law, the dose for a person standing 4 feet from the source of radiation is 0.5 rads.

which error produces a darker radiographic image? a. fixer solution too cold b. film left in the water rinse too long c. film exposed backward in the mouth d. film placed in fixer before developer solution

a. Fixer solution too cold In film processing, the fixer solution hardens the emulsion and clears all unexposed silver halide crystals. If the fixer solution is too cold, a darker image will be produced.

Which restorative materials have the same radiographic appearance? a. gold and amalgam b. porcelain and stainless steel crown c. guttapercha and silver poitns d. composite and porcelain-fused-to metal crown

a. Gold and amalgam both materials appear totally radiopaque.

Which type of caries does NOT involve the enamel surface a. root b. rampant c. recurrent d. interproximal

a. Root Root surface caries involves only the roots of teeth, which includes the cementum and dentin.

Which structure appears radiopaque on a dental radiograph? a. dentin b. air spaces c. dental pulp d. periodontal ligament space

a. dentin Dentin is a tooth structure that appears radiopaque on a dental radiograph.

Which periapical radiograph reveals the anatomic landmark referred to as the inverted Y? a. maxillary canine b. Maxillary incisor c. mandibular molar d. mandibular incisor

a. maxillary canine "inverted Y" refers to the intersection of the maxillary sinus and the nasal cavity and is located superior to the maxillary canine.

The size of the focal spot inside the x-ray tube head determines which radiographic characteristic a. sharpness b. distortion c. density d. magnification

a. sharpness sharpness or detail of the radiographic image is influenced by the size of the focal spot. The smaller the focal spot size, the sharper the image appears

Which is suitable use of panoramic radiograph? a. diagnosis of occlusal caries b. assessment of eruption patterns c. Evaluation of periapical pathology d. measurement of periodontal bone loss

b. Assessment of eruption patterns mages on a panoramic radiograph are not as defined as the images seen on intraoral radiographs; therefore, a panoramic image should be used to assess eruption patterns.

What would be an appropriate reason to expose an occlusal radiograph? a. Mucocele b. Salivary stones c. Advanced bone loss d. measurement of periodontal bone loss

b. Salivary stones occlusal technique provides a supplemental image used when the area of interest is larger than a periapical radiograph may cover, such as a salivary stone.

Which ingredient is the clearing agent found in the fixer solution? a. potassium alum b. ammonium thiosulfate c. acetic acid d. hydroquinone

b. ammonium thiosulfate clearing agent found in the fixer solution; it removes or clears all unexposed and undeveloped silver halide crystals from the film emulsion.

Which of the following is most likely to cause a ghost image to appear on a panoramic radiograph? a. cervical spine b. hearing aid c. dental implant d. tongue

b. hearing aid A hearing aid can contain radiodense or metallic pieces, so it should be removed before panoramic exposure.

Which agent is responsible for converting the exposed silver halide crystals to black metallic silver a. acetic acid b. hydroquinone c. sodium thiosulfate d. ammonium thiosulfate

b. hydroquinone purpose of the developing agent is to reduce the exposed silver halide crystals chemically to black metallic silver. Hydroquinone is one of the chemicals used in the developer.

Which anatomic landmark will appear on an image of the mandibular anterior teeth a. mental ridge b. mental foramen c. mylohyoid ridge d. mandibular canal

b. mental ridge The mental ridge is a linear prominence of bone located on the external surface of the anterior portion of the mandible.

A DH is working in a mobile dental unit and is asked to expose radiographs. Now wall is present in the small x-ray room. What is the minimum distance in feet that the hygienist should stand from the source of the x-radiation a. 4 b. 6 c. 8 d. 10

b. six feet is minimum distance an operator should stand from the source of the primary beam

Which is the standard film size? a. 0 b. 1 c. 2 d. 4

c. 2 The standard size film is the size 2 film.

which of the following is a quality control test used to monitor the strength of the developer solution a. coin test b. light-leak check c. step-wedge radiograph d. half-value layer (HVL)

c. Step-wedge radiograph Creating a step-wedge radiograph allows the operator to compare the film densities produced by the developer on a daily basis.

In bisecting angle technique the central ray of the x-ray beam is directed perpendicular to what plane? a. long axis of the tooth b. long axis of the receptor c. angle formed by the intersection of the long axis of the tooth and receptor d. angle formed by intersection of occlusal plane and the tooth

c. angle formed by the intersection of the long axis of the tooth and receptor bisecting angle technique states that the radiographer must direct the central ray of the x-ray beam perpendicular to the angle formed by the intersection of the long axis of the tooth and receptor. When the angle formed by the plane of the receptor and long axis of the tooth is bisected and the x-ray beam is directed at a right angle to the imaginary bisector, the actual tooth and the image of the tooth will be the same length.

The patient state that movement occurred during x-ray, exposure. Which error will result on the image a. decreased distortion b. Increased sharpness c. decreased sharpness d. Increased magnification

c. decreased sharpness A decrease in image sharpness will occur if the tubehead, patient, or film moves during exposure

Where should the thermometer be kept for manual processing procedures? a. water bath b. fixer solution c. developer solution d. light-tight drawer inside the darkroom

c. developer solution thermometer is a necessary item for manual processing procedures and should be kept in the developer solution.

Which error will produce a lighter radiographic image? a. timer set too long b. film exposed to light c. fixer solution too weak d. developer solution too warm

c. fixer solution too weak If the fixer solution is too weak, a lighter image will result.

Male patient with slight to moderate periodontitis. Declines full mouth series due to concerns with radiation, what is appropriate? a. maxillary and mandibular occlusal radiographs? b. panoramic c. Four vertical bitewings d. four horizontal bitewings

c. four vertical bitewing vertical bite-wing image can be used to examine the level of alveolar bone; these projections are often used for patients with bone loss caused by periodontal disease.

What is the first stage of radiation injury? a. period of injury b. cumulative effects c. latent period d. period of recovery

c. latent period first stage of radiation injury as it relates to the time between exposure to radiation and the appearance of the first observable signs.

Your film exits the automatic processor completely clear. What is the most common reason for this appearance? a. expired film b. exposed to white light c. not exposed to radiation d. exposed backward in the mouth

c. not exposed to radiation If the image is completely clear, the film was not exposed to radiation.

Which speed of film is currently recommened by ADA and the american academy of oral and maxillofacial radiology? (AAOMR) a. C b. D c. E d. F

d. F recommend the use of F-speed film because it results in less patient radiation exposure.

Which exposure factor controls the penetrating power of the x-ray beam? a. time b. voltage c. milliamperage d. kilovoltage peak

d. Kilovoltage peak The kilovoltage peak setting on the exposure control panel determines the quality or penetrating power of the x-ray beam

Which cell is most sensitive to radiation exposure a. muscle b. nerve c. oral mucosa d. bone marrow

d. bone marrow bone marrow is most sensitive tissue to radiation listed

X-rays belong to which category of radiation? a. particulate b. alpha c. beta d. electromagnetic

d. electromagnetic X-rays belong to the group of electromagnetic radiations, which is the propagation of wave-like energy without mass through space or matter.

All the following situations may cause film fogging EXCEPT: a. films stored for several years b. filmed stored near a heat source c. films left in an area exposed to x-radiation d. films left in the fixing solution too long

d. films left in the fixing solution too long Films that are left in the fixing solution too long will become lighter and eventually clear.

All the following landmarks may be viewed on a maxillary incisor periapical image except: A. nasal cavity b. anterior nasal spine c. inferior conchae d. lingual foramen

d. lingual foramen The lingual foramen is a landmark visible in the mandibular anterior region.

Why is a filter placed inside the dental x-ray tubehead a. to eliminate scatter radiation b. to reduce high-energy electrons c. to narrow the size and shape of the x-ray beam d. to remove long-wavelength photons

d. to remove long-wavelength photons Aluminum filters are part of the design of the x-ray tubehead in order to filter the long wavelength, low-energy x-rays from the beam; the long-wavelength, low-energy beam is harmful to the patient and does not contribute to diagnostic imaging.