DANB RHS Exam study questions
Why do we take x rays? - ✔✔To determine the dental health status of a patient beyond the oral
exam.
Periapical (PA) - ✔✔The tissues surrounding the apex of the root of a tooth.
Who benef
...
DANB RHS Exam study questions
Why do we take x rays? - ✔✔To determine the dental health status of a patient beyond the oral
exam.
Periapical (PA) - ✔✔The tissues surrounding the apex of the root of a tooth.
Who benefits from dental xrays? - ✔✔Patient, Practice, Insurance.
What is the primary benefit of an xray? - ✔✔To detect disease.
Decay is the most common reason, Periodontal disease is the second most common reason.
What is the most lucrative reason for an xray in the State of Maine? - ✔✔Trauma xrays make the
most money in the state of Maine (at hospitals)
What is a Dental Fistula? - ✔✔Also called a gum boil or a parulis is an infection at the base of
the tooth which forms inflamed pus. Dental fistula if not treated starts with a tooth abscess and
normally ends on the gingiva or slightly in the oral vestibule.
What can be found in an xray? - ✔✔Developing teeth, missing teeth, supernumary teeth(extra),
impacted teeth, caries(decay), recurrent caries, periodontal disease, dilacerated roots(abnormal
curves), retained root tips, periapical lesions/infections.
Radiopaque - ✔✔The light or white areas of the film. The more dense the tissue or material, the
whiter it will appear.
Radiolucent - ✔✔Dark areas that x rays pass through easily.
Furcation - ✔✔Bone has been eaten away. Usually the result of periodontal disease.
What is the difference between radiographic interpretation and radiographic diagnosis? -
✔✔Interpretation is the ability to read and explain what is revealed by a radiograph. Diagnosis is
giving a disease or condition to the image that is seen.
THE DOCTOR IS THE ONLY ONE WHO CAN LEGALLY GIVE A RADIOGRAPHIC
DIAGNOSIS.
Density - ✔✔The overall darkness of the x-ray picture.
What are the 4 parts of a tooth? - ✔✔Enamel, dentin, root/pulp, cementum.
Contrast - ✔✔Level of differentation between the black/white/grey areas of the film. Higher
contrast is very black and white, lower contrast has more shades of grey.
What are the two things that radiographic contrast depend on? - ✔✔Subject contrast and film
contrast.
What is subject contrast? - ✔✔The result of differences in absorption of the xray by tissues.
What are the three factors in subject contrast? - ✔✔THE PATIENT:Each tissue has a different
contrast. Depending on size, the patient may have more levels of tissue for greater contrast.
KVP:this is the quality of the xray beam. the higher the beam, the more wavelengths are
produced and the greater the potential for contrast.
SCATTER RADIATION:The more that this sort of xray hits the film, the more it is exposed and
the kess contrast the picture will eventually take on.
What is film contrast? - ✔✔The contrast that comes from characteristics of the film and
processing.
What are the three factors in film contrast? - ✔✔Film type, exposure time(over and undereposed
films will result in poor contrast), processing(if done incorrectly, it may ruin the contrast built
into the film by the manufacturer.
What happens if a film is exposed to too much/too little light? - ✔✔Too much-darker
Too little-lighter
Foreshortening - ✔✔Excessive vertical angulation. Ex. For the upper Maxillary arch angle, point
the xray beam downward and it will cause the teeth to appear short.
Elongation - ✔✔Insufficient vertical angulation. Ex. For the upper Maxillary arch angle, point
the xray beam upward and it will cause the teeth to appear long.
Cone cut - ✔✔The central beam misses the center of the film and produces a blank area cutting
off the edge/corner of the film.
Sharpness - ✔✔The clarity of the outline of the structures on an x ray.
What are the two factors that effect sharpness? - ✔✔GEOMETRIC FACTORS: Focal spot
size(spot that makes the xray), movement, and distances between machine, film, and object.
CRYSTAL SIZE: The larger the crystals the less sharp. "resolution"
What factors control the outcome of contrast and density in an xray? - ✔✔Milliamperage,
exposure time, Kilovoltage, distance(tubehead length)
Milliamperage (MA) - ✔✔The amount of current that is running through an xray machine. The
more MA, the higher number(quantity)of xrays produced, the denser the image.
Exposure time - ✔✔The length of time that the xray machine is on.(the length of time your
finger is on the button)
Kilovoltage peak (kvp) - ✔✔The circuit that determines the QUALITY and quantity of an xray.
Higher kvp, the shorter the wavelength, the higher the density. KVP is the only factor that
controls contrast as well.
PID - ✔✔Position indicating device
Gamma ray - ✔✔The only thing faster than an xray.
What are the types of distance that effect the quality of an xray? - ✔✔Source of xray and skin
surface, tooth and film, xray and film.
What is source to skin distance? - ✔✔The length of the PID determines the distance. The end of
the PID should almost touch the skin
[Show More]