Lecture 7 Flashcards
What is the error in this picture?
Unexposed receptor
What is an unexposed receptor?
A receptor that has not been exposed to x-radiation.
What types of receptors can experience unexposure errors?
This error may occur with digital sensors (direct or indirect) or film.
How does an unexposed receptor appear when using film?
The image appears clear.
How does an unexposed receptor appear when using a digital sensor?
The image appears blank or white with no anatomic structures recorded.
What may a PSP show if it is unexposed?
It may show a previous radiograph that has not been scanned.
What is a possible cause of an unexposed receptor?
The receptor was not exposed to x-radiation.
What is a correction to ensure proper exposure?
Make certain that the x-ray machine is turned on.
What should you listen for during exposure?
Listen for the audible exposure signal.
What is important regarding the PID during exposure?
Make certain the PID is centered over the receptor.
What should you be aware of with digital imaging systems?
Be aware of the time interval during which exposures must occur prior to the system ‘timing out.’
What is the error in this picture?
Film exposed to light
What is the appearance of film exposed to light?
The image appears black.
What causes film to appear black?
The film was accidentally exposed to white light.
How can you correct the exposure error?
Do not take out the dental film out of its packet prior to exposure.
Unwrap the film packet in a darkroom.
What is the error with this image?
Overexposed receptor
What does an overexposed receptor error look like?
This error may occur with digital sensors (direct or indirect) or film.
What does an overexposed image look like?
The image appears dark or high in density.
What causes receptor overexposure?
The receptor was exposed to too much radiation. An overexposed image results from excessive exposure time, kilovoltage, or milliamperage, or a combination of these factors.
What is the most common cause of overexposure?
Too much exposure time is the most common cause of overexposure.
To prevent an overexposed receptor what should the operator do?
To limit patient exposure, operators should use an kilovoltage setting of 60 to 80 kV
• a milliamperage setting of 6 to 8 mA
• the shortest exposure time possible to create a diagnostic image.
What is the error with this image?
Receptor was underexposed
What happens with an underexposed receptor and what type of receptor is involved?
An underexposed receptor is a digital sensor (direct or indirect) or film that has not received sufficient radiation exposure.
This error may occur with digital sensors or film.
What does an underexposed image look like?
The image appears light or low in density.
This is a visual indication of underexposure.
What causes underexposure?
The receptor was exposed to too little radiation, often due to inadequate exposure time, kilovoltage, or milliamperage.
Too little exposure time is the most common cause.
How can underexposure be corrected?
Check the exposure time, kilovoltage, and milliamperage settings on the x-ray machine before exposing the receptor.
Are there different settings for adults and children?
Yes, there are different settings for adult and child exposures.
Receptor Placement Error for PAs occurs with what type of receptor?
This error may occur with digital sensors (direct or indirect) or film.
Receptor Placement Error for PAs can occur when using which techniques?
This error may occur with the paralleling or bisecting technique.
What is the result of a Receptor Placement Error during PAs?
Desired anatomy features are not captured in the radiograph.
What causes a Receptor Placement Error for PAs?
The receptor was not positioned in the patient’s mouth to cover the apical regions of teeth.
What is an error for PSPs in relation to Receptor Placement Error for PAs?
The letter ‘a’ covers the apex of the root.
How can a Receptor Placement Error for PAs be corrected?
XCP and a receptor are positioned correctly
Teeth are firmly contacting the bite-block.
Make certain that the teeth are fully biting on the bite block.
Make sure to check that the patient did not close only with his/her lips.
What is the error in the photo?
Patient’s teeth are not firmly biting the bite block
What is the error in the picture?
Patient is not biting down all the way on bite block during BWX exposure
What is the error in this picture?
Unequal distribution caused by not ensuring that maxillary and mandibular arch teeth where equally distributed; also could be a vertical angulation issue
Receptor Placement Error in Bite-Wing Imaging occurs with what type of receptors?
Receptor Placement Error may occur with digital sensors (direct or indirect) or film.
What is the appearance of BWX after incorrectly placing the sensor?
Desired anatomy features are not captured in the radiograph.
What causes Receptor Placement Error for BWX?
The receptor was not positioned such that the maxillary and mandibular teeth and tissues are equally, fully captured.
How can Receptor Placement Error for BWX be corrected?
Teeth are firmly contacting the bite-block. Make certain that the teeth are fully biting on the bite block. Make sure to check that the patient did not close only with his/her lips. Make sure sensor is evenly distributed between arches.
What issue can arise from horizontal angulation error for BWX?
Interproximal contact overlaps.
What issue can arise from vertical angulation error for BWX?
Crestal bone in both arches not captured.
What is a common error when placing the receptor for premolar BW?
The receptor is not placed following the curvature of the teeth arch.
What is a common error when placing the receptor for molar BW?
The receptor is not placed distal enough.
What is the error in this picture?
Dropped receptor corner
a Dropped Receptor Corner occurs with what type of receptor?
digital sensors (direct or indirect) or film.
a Dropped Receptor Corner error can occur during what techniques?
This error may occur with the paralleling or bisecting technique.
What is the appearance of a Dropped Receptor Corner error?
The occlusal plane appears tipped or tilted.
What causes a Dropped Receptor Corner?
The edge of the receptor was not placed parallel to the incisal-occlusal surfaces of teeth.
A corner of the receptor may slip or drop if the patient is not firmly closed on the bite-block.
What should the operator always do before taking a radiograph?
Always examine the patient’s mouth prior to taking the radiograph!
What is important to provide to the patient before taking a radiograph?
Clear instructions to the patient.
What should the operator look out for when preparing for a radiograph?
Tori, gag reflex, missing teeth, rotated teeth, misaligned teeth, shallow palate, narrow arch teeth.
Are anatomical variations excuses for radiograph re-takes?
These are not excuses for radiograph re-takes if you could have modified your techniques!
What can improper Horizontal Angulation cause?
Overlapped contacts
What can improper Vertical Angulation cause?
Foreshortened images and Elongated images
What is the error in this pic?
Overlapping contacts caused by improper horizontal angulation
What is the most common result of incorrect horizontal angulation?
The most common result of incorrect horizontal angulation is “overlapped contacts,” where the contact areas between adjacent teeth appear superimposed on the radiograph.
What types of receptors can experience errors due to incorrect horizontal angulation?
This error may occur with all types of receptors, including digital sensors (both direct and indirect) as well as traditional film.
Which radiographic techniques can lead to overlapped contacts if horizontal angulation is incorrect?
Overlapped contacts due to incorrect horizontal angulation can occur with both the paralleling technique and the bisecting angle technique.
How does the appearance of overlapped contacts manifest on a radiograph?
On the radiograph, overlapped contacts appear as superimposed contact areas between adjacent teeth, making it difficult to assess interproximal spaces.
What causes overlapped contacts in radiographs?
The primary cause of overlapped contacts is the improper alignment of the central X-ray beam, which is not directed perpendicularly through the interproximal spaces of the teeth.
How can you correct overlapped contacts caused by incorrect horizontal angulation?
To avoid overlapped contacts on a periapical image, ensure that the central X-ray beam is directed precisely through the proximal contacts of the teeth, aligning it perpendicularly to the contact points.
What error this?
Forshortening caused by incorrect vertical angulation
What is a foreshortened image?
A foreshortened image is one that is shorter than the actual tooth.
What causes foreshortened images?
The vertical angulation was excessive (too steep).
foreshortened images occur using what type of receptor?
Foreshortened images may occur with digital sensors (direct or indirect) or film.
In which technique can foreshortened images occur?
This error may occur with the bisecting technique when a beam alignment device is not used.
How do foreshortened images appear?
Teeth appear short with blunted roots on the image.
How can foreshortened images be corrected?
To avoid foreshortened images, do not use a steep vertical angulation with the bisecting technique.
What type of error is this?
Elongated imaged caused by improper vertical angulation
What are elongated images?
Elongated images are images where teeth appear long and distorted.
What causes elongated images?
Elongated images are caused by insufficient vertical angulation (too flat).
In what scenarios can elongated images occur?
Elongated images may occur with digital sensors (direct or indirect) or film.
When does the bisecting technique lead to elongated images?
The bisecting technique can lead to elongated images when a beam alignment device is not used.
What types of receptors can experience vertical angulation errors in BWX?
Vertical angulation errors in bitewing X-rays (BWX) can occur with all types of receptors, including digital sensors (both direct and indirect) and traditional film.
Which radiographic technique is prone to vertical angulation errors in BWX?
Vertical angulation errors in BWX are commonly associated with the bitewing technique, especially when a bite-tab is used or when outdated XCP (Extension Cone Paralleling) components are employed.
How does incorrect vertical angulation affect the appearance of a BWX radiograph?
In BWX radiographs, incorrect vertical angulation causes the following:
- A negative or positive vertical angulation , resulting in improper imaging.
- The upper or lower alveolar bone may be excluded
- A distorted image is produced, reducing the diagnostic accuracy of the radiograph.
- The occlusal surfaces of the mandibular or maxillary teeth are overly visible, indicating improper beam alignment.
How can vertical angulation errors in BWX radiographs be prevented?
To avoid vertical angulation errors in BWX radiographs:
- Set the correct vertical angulation, ensuring the X-ray beam is properly aligned to capture all relevant structures.
- Use properly calibrated and modern XCP holders or bite tabs for positioning.
- Avoid using outdated or worn equipment that can compromise the accuracy of beam alignment.
What is a cone-cut error in radiography?
A cone-cut error occurs when the X-ray beam does not fully cover the receptor, resulting in a clear or white (unexposed) area on the image.
What shapes can a cone-cut error appear as on a radiograph?
A cone-cut error can appear as either a linear or curved unexposed area, depending on the alignment of the beam and the receptor.
Which types of receptors are affected by cone-cut errors?
Cone-cut errors can occur with all types of receptors, including digital sensors (direct or indirect) and traditional film.
Which radiographic techniques can result in cone-cut errors?
Cone-cut errors can happen with any radiographic technique, including the paralleling, bisecting, and bitewing techniques.
How does a cone-cut error appear on a radiograph?
A cone-cut error appears as a clear or white (unexposed) area on the image, indicating that part of the receptor was not exposed to the X-ray beam.
What causes a cone-cut error in radiography?
The primary cause of a cone-cut error is improper alignment of the PID (Position Indicating Device) with the beam alignment device. This misalignment prevents the X-ray beam from fully exposing the receptor.
How can cone-cut errors be prevented?
To avoid cone-cut errors:
- Carefully position the PID to ensure proper alignment with the beam alignment device.
- Make certain that the PID and the aiming ring are flush and aligned correctly before exposing the receptor.
- Double-check the alignment to ensure the X-ray beam fully covers the receptor.
What kind of error is this?
Bending
In what type of receptor does a bending error occur?
A bending error may occur with indirect digital sensors (PSP receptors) or film. Bending cannot occur with direct digital sensors.
With which techniques can a bending error occur?
This error may occur with the paralleling, bisecting, or bite-wing techniques.
How does a bending error appear on an image?
The image appears stretched and distorted on a film and on PSP receptors.
What type of error is this?
Creasing
What is creasing in radiography, and what is its impact on the image?
Creasing occurs when the receptor is bent or folded during handling. It causes permanent artifacts on the image, such as lines that affect diagnostic quality.
Which types of receptors can experience creasing?
Creasing can occur with indirect digital sensors (PSP receptors) or film. However, it cannot occur with direct digital sensors, as they are rigid and not prone to bending.
Which radiographic techniques are prone to creasing errors?
Creasing can occur with any technique, including the paralleling, bisecting, or bite-wing techniques.
How does creasing appear on a radiograph?
When using film, creasing appears as a thin radiolucent line on the image. When using a PSP receptor, creasing appears as a white line on the image.
What causes creasing in radiography?
Creasing is caused by improper handling of the receptor. This includes bending or overmanipulating the receptor to enhance patient comfort, which can permanently damage it.
How can creasing errors be prevented?
Handle the receptor carefully and avoid overmanipulating it. Be gentle when positioning the receptor to ensure patient comfort without causing damage. Inspect PSP plate receptors for signs of damage, as creased receptors will produce artifacts on every image. Replace damaged plate receptors to maintain image quality.
What type of error is this?
Debris
What is debris accumulation in radiography, and what is its impact on the image?
Debris accumulation refers to the presence of dirt, dust, or other particles on the surface of a digital sensor. This can result in permanent radiopaque artifacts or radiolucent scratch marks on the radiograph, compromising its diagnostic quality.
Which type of receptor is prone to debris accumulation?
Debris accumulation primarily occurs with digital sensors, as their surfaces can attract dirt or dust particles during handling.
Which radiographic techniques are prone to errors caused by debris accumulation?
This issue can occur with any technique, including the paralleling, bisecting, or bite-wing techniques.
How does debris accumulation appear on a radiograph?
Debris on the sensor’s surface may cause radiopaque artifacts, appearing as bright spots on the image. If the sensor is scratched, radiolucent lines or marks may appear, which are darker than the surrounding image.
What causes debris accumulation on digital sensors?
The accumulation of debris is typically caused by improper handling of the sensor or failing to clean it between uses. Dirt, dust, or particles can settle on the sensor’s surface, particularly if infection prevention protocols are not followed.
How can debris accumulation be prevented?
Follow correct infection prevention procedures to ensure the sensor is properly maintained between uses. Regularly wipe the sensor surface with appropriate cleaning materials to remove dirt or dust. Handle the sensor carefully to avoid scratches or other permanent damage.
What type of error is this?
Phalangioma
What type of error is this?
Double image
What is a phalangioma in radiography, and how does it occur?
A phalangioma occurs when an image of the patient’s finger is accidentally captured on the radiograph. This happens when the patient holds the receptor with their fingers during the exposure.
Which types of receptors are affected by phalangioma errors?
Phalangioma errors can occur with both digital receptors and film.
Which radiographic technique is most associated with phalangioma errors?
This error is most often associated with the bisecting technique, specifically when the finger-holding method is used during exposure. This technique is not recommended.
How does a phalangioma appear on a radiograph?
The image of the patient’s finger bone (phalanges) is visible on the radiograph, interfering with the diagnostic image.
How can phalangioma errors be prevented?
Never allow a patient to hold the receptor during exposure. The operator should also avoid holding the receptor with their fingers. Use proper positioning devices (e.g., XCP holders) to stabilize the receptor and eliminate the need for finger-holding.
What is a double image in radiography, and what causes it?
A double image occurs when the same receptor is exposed twice without erasing or processing it, leading to overlapping structures and a darkened, superimposed image.
Which types of receptors are prone to double image errors?
Double image errors can occur with indirect digital sensors (PSP receptors) or film. However, they cannot occur with direct digital sensors, as these are erased or reset after each exposure.
Which radiographic techniques are associated with double image errors?
Double image errors can occur with any radiographic technique, including the paralleling, bisecting, or bite-wing techniques.
How does a double image appear on a radiograph?
A double image appears as a darkened image with superimposed structures, making it difficult to interpret and compromising the diagnostic quality.
What causes double image errors in radiography?
This error occurs when a receptor, such as a PSP plate or film, is exposed twice without being properly erased or processed between exposures.
How can double image errors be prevented?
Ensure that PSP plates are properly erased before reuse. Verify that film is processed and cleared before reusing. Follow strict procedural protocols to avoid accidental double exposures. Handle receptors carefully and ensure proper workflow to prevent this issue.
What type of error is this?
Unsharpness
What is movement/motion unsharpness in radiography?
Movement or motion unsharpness refers to a radiographic error where the image appears blurred due to movement of the patient, receptor, or X-ray tube during the exposure.
Which types of receptors are prone to motion unsharpness errors?
This error can occur with digital sensors, as they are sensitive to motion during exposure.
Which radiographic technique is most associated with motion unsharpness errors?
Motion unsharpness errors are commonly seen in the paralleling technique, but they can occur with any radiographic technique if movement happens during the exposure.
How does motion unsharpness appear on a radiograph?
The resulting radiograph will appear blurred, making it difficult to clearly identify structures and compromising diagnostic accuracy.
What causes movement or motion unsharpness in radiographs?
Movement by the patient during the X-ray exposure.
Movement of the receptor or X-ray tube head during the exposure.
How can movement/motion unsharpness errors be prevented?
Provide clear instructions to the patient to remain still during the exposure.
Ensure the operator has proficiency and performs the technique quickly and efficiently to minimize the chance of patient movement.
Stabilize the receptor and X-ray tube head securely to avoid accidental movement.
What kind of error is this?
Reversed backward placement
What is reversed/backward placement in radiography?
Reversed or backward placement occurs when the receptor (digital sensor or film) is placed incorrectly in the mouth, with the wrong side facing the X-ray beam, leading to an incorrect image.
Which types of receptors are affected by reversed/backward placement errors?
This error can occur with digital sensors or film.
Which radiographic techniques are prone to reversed/backward placement errors?
Reversed/backward placement errors can happen with the paralleling, bisecting, or bite-wing techniques.
How does reversed/backward placement appear on a radiograph?
With film: A light image with a herringbone pattern is seen. This pattern is caused by the embossed lead foil backing in the film packet being exposed to the X-ray beam.
With digital sensors: A blank or white image is produced, with no anatomic structures recorded.
What causes reversed/backward placement in radiographs?
This error occurs when the film or digital sensor is placed in the mouth incorrectly, with the side intended to face away from the beam accidentally facing it instead.
How can reversed/backward placement errors be prevented?
Double-check the orientation of the receptor before positioning it in the patient’s mouth.
For film, ensure the white side of the film packet is facing the X-ray beam.
For digital sensors, follow the manufacturer’s guidelines to ensure the correct side of the sensor is facing the beam.
Provide proper training for radiographic positioning to avoid orientation mistakes.
What type of error is this?
Wire cable issues
What are wired cable issues in radiography, and when do they occur?
Wired cable issues occur when the cable of a direct digital sensor interferes with the X-ray beam, resulting in a radiopaque outline of the cable on the radiograph.
Which type of receptor is affected by wired cable issues?
This error occurs exclusively with direct digital sensors that are linked to the computer via a fiber-optic cable.
Which radiographic techniques are prone to wired cable issues?
Wired cable issues can happen with the paralleling, bisecting, or bite-wing techniques.
How do wired cable issues appear on a radiograph?
A wired cable issue results in a radiopaque outline of the cable appearing on the image, which can obscure anatomical structures and compromise diagnostic accuracy.
What causes wired cable issues in radiography?
The error occurs when the sensor cable is positioned between the sensor and the X-ray beam during exposure, blocking part of the X-ray beam and leaving its outline on the radiograph.
How can wired cable issues be prevented?
Ensure the cable is positioned away from the X-ray beam before taking the exposure. Use the XCP (beam alignment device) correctly to secure the sensor and cable in place. Follow the manufacturer’s instructions for sensor and cable placement to avoid interference. Confirm that the cable is secure and the patient is not biting on the cable, which can damage the cable or misalign it. Double-check the sensor and cable alignment before exposing the radiograph.
