EXTRAORAL PANORAMIC ERRORS - SUMMARY (by SmarterDA)
I often refer a radiographic exposure to a photoshoot session to our SmarterDA (Dental Assisting exam prep) users. The camera person is the clinician, and the model is the patient. To create the best effect, the photographer (clinician) should provide excellent instructions.
Panoramic radiography can be used in the following situations; for general surveys of oral health, to determine the best radiographic supplements for surgical procedures, for initial and progressive evaluations of orthodontic treatment, for information about pediatric growth and development, to review chronological dental eruptions and the axes of permanent tooth eruptions, to evaluate cystic or neoplastic lesions, to measure the dimensions for implantology, for historical documentation, to evaluate the temporomandibular joint, and to detect the presence of foreign bodies.1
According to the research conducted on positioning errors and published in Imaging Science in Dentistry, about 90% of panoramic images were presented with errors while only about 10% were error free. The ranking of positioning errors are as follows:2
1. Tongue not touching the palate during exposure (55.7%)
2. Slumped position (35%)
3. Patient positioned back (30%)
4. Patient positioned forward (18.3%)
5. Chin tipped high (17.9%)
6. Head is turned to one side (17.4%)
7. Chin tipped low (16.2%)
8. Head is tilted to the side (12.7%)
9. Patient movement during exposure (1.6%)
This article aims at summarizing how to detect the panoramic radiographic errors and to provide instructions on how to correct them. The goal is to successfully pass the dental assisting board exams and also to become the superstar dental assistant everyone wants on their team!
1. De Senna BR, Dos Santos Silva VK, França JP, Marques LS, Pereira LJ. Imaging diagnosis of the temporomandibular joint: critical review of indications and new perspectives. Oral Radiol. 2009; 25:86–98
2. Dhillon M, Raju SM, Verma S, Tomar D, Mohan RS, Lakhanpal M, et al. Positioning errors and quality assessment in panoramic radiography. Imaging Sci Dent. 2012; 42:207–212.
Panoramic Radiograph Errors + How to correct them [SUMMARY]
Error: Branch like marks, round clusters
Cause: Static electricity occurred when removing film from cassette
Correction: Avoid rapid removal of film from cassette
Error: White opacity at the bottom of film shaped like inverted “V” (also called “shark fin’ error)
Cause: Lead apron is above the collar line
Correction: Lower the apron
Note: The panoramic radiograph lead apron does NOT have a color
Error: Unwanted white opacity
Cause: Metal foreign object (tongue ring, piercing, braces, etc.) is present
Correction: Remove object prior to exposure if possible
Ghost image (magnified, blurry, and displayed on the opposite side of the radiographic image)
Note: Ghost image can also be of a body part such as the ramus
Error: White tapered opacity in middle of image (also called Washington Monument error)
Cause: Patient’s spine is slumped
Correction: Have patient take a step forward, straighten the back/neck, and lean slightly back
Error: Large, dark shadow over maxillary teeth between palate and dorsum of tongue
Cause: Patient’s tongue is not touching the roof of mouth
Correction: Instruct patient to place tongue in roof of mouth prior to exposure
Error: Thin and blurry anterior teeth, spine visible on sides of film
Cause: Patient is biting too far forward on the rod
Correction: Make sure anterior teeth are in grooves on the bite block
Error: Fat and blurry anterior teeth, condyles close to edge of film
Cause: Patient is biting too far back on rod
Correction: Make sure anterior teeth are in grooves on the bite block
Error: Exaggerated smile line, condyles at the top of film, spine forms arch
Cause: Patient’s chin is tipped too far down
Correction: Position the Frankfurt line (bottom of orbit to the middle of the ear) parallel to the floor
Error: Flat smile line, hard palate superimposed on roots, broad and flat mandible, condyles at edge of film
Cause: Patient’s chin is tipped too far up
Correction: Position the Frankfurt line (bottom of orbit to the middle of the ear) parallel to the floor
Error: Teeth and ramus are wider on one side
Cause: Patient’s head is twisted
Correction: Center the head’s midline, use the beam guides
Note: The side with the wider condyle is the side closer to the tubehead)
Error: Condyles are not equal in height
Cause: Patient’s is head tipped
Correction: Reposition head using proper guidelines for the machine
Error: Blurred portions of radiograph, large defects
Cause: Patient moved during exposure
Correction: Instruct patient to hold still prior to and during exposure
Error: Images of springs or rectangular radiolucencies visible on film
Cause: Cassette was placed in machine backward
Correction: Follow instructions on the cassette (e.g., this side faces the tubehead, right/left, this side up, etc.).
If instructions are not provided, create markings for future reference (e.g., write with a marker: This side tubehead, etc.)
As you can see, small details can make a difference. As a dental professional, it is important to minimize the exposure to radiograph, therefore, avoid re-takes.
Type: YouTube + SmarterDA
Watch the videos, understand the concepts, and PASS the exams!