Occlusal and Skull Radiography Flashcards
What are the film/PSPP sizes?
0: Pediatric
1: Anterior PA, Pediatric
2: Standard
3: Special BW (no longer in common use)
4: Occlusal
What are the advantages of occlusal radiographs?
- Larger size receptors allow larger segments of the jaw to be examined.
- For use when patients are unable to open mouth wide enough for peri-apicals due to pain, trismus, etc
What are the clinical indications for occusal radiography?
- Roots, impactions, supernumeraries
- Foreign bodies
- Localization of stones in ducts
- Alteration to cortical bone
- Sinus and nasal integrity
- Fractures
- Extent of pathoses
What are the three different types of maxillary occlusal radiography?
- Standard Cross-Sectional
- Lateral (right/left) Cross-sectional
- Anterior Topographical
What are the three different types of mandibular occlusal radiography?
- Standard Cross-Sectional
- Lateral (right/left) Cross-Sectional
- Anterior Topographical
What is the vertical angle of the standard cross-sectional maxillary occlusal radiograph?
(+) 65 to 70 degrees
(pointed downward)
Where is the central ray (CR) placed for the standard cross-sectional maxillary occlusal radiograph?
bridge of nose and center of PSP Plate
What is the vertical angle of the lateral cross-sectional maxillary occlusal radiograph?
(+)55-60 degrees
(pointed downward)
Where is the central ray (CR) placed for the lateral cross-sectional maxillary occlusal radiograph?
posterior maxilla
What is the vertical angle of the anterior topographical maxillary occlusal radiograph?
(+) 55 to 60 degrees
(pointed downward)
Where is the central ray (CR) placed for the anterior topographical maxillary occlusal radiograph?
¼ to ½ inches above tip of nose
What type of radiograph is this?
standard cross-sectional maxillary occlusal radiograph
What type of radiograph is this?
lateral cross-sectional maxillary occlusal radiograph
What type of radiograph is this?
anterior topographical maxillary occlusal radiograph
What is the vertical angle of the standard cross-sectional mandibular occlusal radiograph?
perpendicular to PSP
Where is the central ray (CR) placed for the standard cross-sectional mandibular occlusal radiograph?
between mandibular first molars; along mid-sagittal plane; move beam away about 2 inches or 5cm
What type of film must you use for occlusal radiographs?
you must use PSP or film for occlusal radiographs because no company makes solid state occlusal sensors because they wouldn’t make enough money (not enough demand)
What type of radiograph is this?
standard cross-sectional mandibular occlusal radiograph
What is the vertical angle of the lateral cross-sectional mandibular occlusal radiograph?
perpendicular to PSP Plate following long axis of first molar
Where is the central ray (CR) placed for the lateral cross-sectional mandibular occlusal radiograph?
center of PSP Plate @ apex of first molar
What type of radiograph is this?
lateral cross-sectioanl mandibular occlusal radiograph
What is the vertical angle of the anterior topographical mandibular occlusal radiograph?
(-)55 to 60 degrees (pointed upward); Bisecting angle between PSP Plate and long axis of incisor teeth
Where is the central ray (CR) placed for the anterior topographical mandibular occlusal radiograph?
below apices of incisors, 1 cm above tip of chin, along midline of chin, direct at center of PSP Plate
What type of radiograph is this?
anterior topographical mandibular occlusal radiograph
The occlusal radiograph exposure settings need to be turned up ____ exposure settings higher than posterior maxillary periapcial exposures
1 or 2
What film do you use for pediatric occlusal radiography?
number 2 intraoral plate
What is included in skull radiography?
● orthodontic evaluations
● orthognathic evaluations
● pathology beyond coverage of standard dental images
What are the different types of skull projections?
–Lateral cephalogram/cephalometric
–PA cephalogram/cephalometric
–Waters’ PA
–Reverse-Towne (PA)
–SMV
What are image enhancers?
- Grids
– standard
– focused
– grid ratios - Air Gaps
What do the grids with PSPP do?
Reduce amount of scatter radiation exposing film and improves image contrast
Increasing the tube-object distance does what?
photons will be less divergent and more parallel before interacting with tooth
- decreases magnification
- maximize sharpness
What are the characteristics of a lateral skull projection within cephalostat?
- Beam is 90 degrees to mid-sagittal skull plane and sensor
- Mid-sagittal skull plane and sensor are parallel
- Frankfort Plan parallel to Horizontal (ground)
What radiograph is this?
lateral cephalogram
What should you be able to identify on a lateral cephalogram?
● Maxillary Sinus
● Frontal Sinus
● Sphenoid Sinus
What radiograph is this?
lateral cephalometric radiograph
- shows soft tissue
What are the characteristics of cephalometric radiography?
- Used for taking measurements and evaluating the effect of growth or disease on a skeletal profile
- Positioning is “standardized” for retrospective or predictive evaluation of skeletal changes
- Standardized 60” focal distance used to
- standardize magnification and,
- improve resolution - Soft tissue profiles often specified for lateral skull evaluations
- Soft tissue filters are applied either at the source or at the film
How can you add a soft tissue filter?
- at source
- at receptor
– over grid
– over intensifying screen
What is the lateral cephalometric image used for?
used for orthodontic and orthognathic surgical treatment
What are the characteristics of the PA skull?
- Beam is 90 degree to sensor and parallel to mid-sagittal skull plane
- Coronal (Frontal) skull plane is 90 degrees to sensor
What radiograph is this?
PA Skull
What are the characteristics of the waters’ (occipitomental) skull radiograph?
- Beam is 90 degrees to sensor and parallel to mid-sagittal skull plane
- Mid-sagittal skull plane is 90 degrees to sensor, but chin is raised to touch sensor
What radiograph is this?
waters’ (occipitomental) skull radiograph
What are the characteristics of the submentovertex (basilar) skull radiograph?
- Beam is 90 degrees to sensor and axial skull plane
- Mid-sagittal skull plane is 90 degrees to sensor, but vertex is adjacent sensor
What radiograph is this?
submentovertex (basilar) skull radiograph
