1/25/17 Taking Radiographs Flashcards
In the intraoral examination what four things do you look for?
- Missing teeth
- Existing restorations
- Caries
- Anomolies
What does a black line through a tooth on an odontogram mean?
-Congenitally missing
What does a blue line through a tooth on an odontogram mean?
-Previously extracted
When you chart an existing restoration of a composite resin on an odontogram what do you do?
-Outline surfaces in Blue
What does a red line through a tooth on an odontogram mean?
-Needs to be done
When you chart an existing restoration of an amalgam on an odontongram what do you use?
-Fill in surfaces in blue
When you chart a gold restoration on an odontogram how do you mark it?
-Cross hatch surfaces in Blue
When you have a porcelain or ceramic crown charted on an odontogram how do you mark it?
-Outline tooth in blue
If you have a tooth that is outlined in red what does that mean?
-You have treatment planned to place a ceramic/porcelain crown
If you have a tooth that is crosshatched in blue what does that mean?
-You have placed a gold crown/restoration on a tooth
On a bridge what is the tooth that is being replaced called?
-Pontic
What are three ways to maximize sharpness and resolution on a radiograph?
- Use as small an effective focal spot as practical
- Increase distance from focal spot to object with long open ended cylinder
- Minimize distance from object to image receptor (film next to tooth)
T/F The smaller the focal spot the sharper the image
True
What are two ways to minimize image size distortion?
- Increase focal spot to image receptor distance
- Decrease object to image receptor distance (film placement)
What are two ways to minimize image shape distortion?
- Position image receptor (film) parallel to long axis of the object (tooth)
- Orient central ray (cone) perpendicular to the object and image receptor
When does foreshortening occur?
-Occurs when the central beam is perpendicular to the image receptor (film), but the object (tooth) is not
When does elongation occur?
-Occurs when the central beam is perpendicular to the object (tooth), but not the image receptor (film)
In the paralleling technique where should the central ray be?
-Perpendicular to the long axes of both the tooth and the image receptor
What technique generates the least distortion and is the preferred method of capturing images when possible?
-Paralleling technique
In the bisecting technique where should the central beam be?
-Directed at a right angle to the imaginary plane bisecting the angle formed by the image receptor (film) and the central axis of the object (tooth)
What does the bisecting-angle technique result in?
-Image is the correct length, but the tooth is distorted and the height of the alveolar crest is distorted
What does SLOB rule stand for?
-Same Lingual Opposite Buccal
If you move the tube head to the right and the object also moves to the right where is it located in relation to the teeth (widening the distance from the tooth)?
-Lingual
How can you obtain greater periapical coverage than you normally obtain in the conventional technique?
-Increase the vertical angulation from 5 -15 degrees
To lessen distortion in a radiograph you can :
A) increase distance between focal spot and image receptor
B) Decrease distance between object and image receptor
C) Use paralleling technique
D) all of the above
D) all of the above
In a full mouth series of radiographs how many films do you use?
- 18 #2 sensor
- 21 #1 sensor for anteriors #2 for everything else
Of the 18 films you use in a full mouth series of radiographs how many PA and BW films do you use?
- 14 PAs
- 4 BWs
When you take a radiograph on the maxillary central incisors where do you line up the Central x-ray entry point?
-Tip of the nose
When you take a radiograph of the maxillary canine where is the central x-ray entry point?
-Corner of the nose (Ala)
When you take a radiograph of the maxillary bicuspids where is the central x-ray entry point?
-Point down from the pupil of the eye to mid cheek area
When you take a radiograph of the maxillary molars where is the central x-ray entry point?
-Point down from the outer canthus (corner of eye) to middle cheek area
When you take a radiograph of the mandibular molars where is the central x-ray entry point?
-Point down from the outer canthus (corner of eye) to mid-mandible area
When you take a radiograph of the mandibular bicuspids where is the central x-ray entry point?
-Point down from the pupil of the eye to mid-mandible area
When you take a radiograph of the mandibular cusipds where is the central x-ray entry point?
-Point down from the ala of the nose to the chin corner
When you take a radiograph of the mandibular centrals where is the central x-ray entry point?
- Point down from the tip of the nose to the center of the chin
When you take a radiograph of a bicuspid bitewing where is the central x-ray entry point?
-Point down from the pupil of the eye to the occlusal plane
When you take a radiograph of the molar bitewing where is the central x-ray entry point?
-Point down from the outer corner of the eye to the occlusal plane
When taking periapical radiographs of the upper bicuspids you do which of the following?
A) position the center of the cone below the ala of the nose
B) Position the sensor such that it captures the distal of the cuspid and mesial of the first molar
C) Angle the cone from the mesial in order to project the cuspid onto the sensor
D) all of the above
B) Position the sensor such that it captures the distal of the buspid and mesial of the first molar
What describes any substance that permits the transmission of x-rays?
-Radiolucent
What describes any substance that blocks the transmission of x-rays?
-Radiopaque
What color is a radiolucent image on the radiograph?
-Black
Which is more radiopaque: Metal or resin?
-Metal
What is more radiolucent Cementum or Dentin?
-Cementum
What is more radiopaque Cortical bone or cementum?
-Cementum
