Radiographic Techniques 2 Flashcards
1
Q
Why should we take bitewings?
A
- Detect caries
- Monitor caries progression
- Assess periodontal status
- Assess existing restorations
2
Q
What is the difference between Horizontal and Vertical bitewing?
A
Horizontal
- Long axis of film horizontal
- Usually one each side
- Demonstrate distal 4 to mesial 8
- Unless the request states differently
- Demonstrate crowns & 1/3 roots
Vertical
- Long axis of film vertical
- 2 each side
- Demonstrate pre-molars and molars
- Will demonstrate more of the roots.
3
Q
How do you decide to use a horizontal or vertical bitewing?
A
Horizontal
- Caries assessment
- Perio assessment
Vertical
- Caries assessement
- Perio assessment: when you need to see more of the root and supporting bone
4
Q
What are the Positioning requirements for bitewings?
A
- Film and object parallel
- Film close to object
- X-ray beam perpendicular to object and film
Always use a holder!!
5
Q
What are the 2 holder types?
A
Rigid plastic
- Holds film accurately
- Assists x-ray tube positioning
- Uncomfortable
Paper tab
- Comfortable
- X-ray tube positioned by eye
- Inaccurate positioning
6
Q
What is a Horizontal overlap?
A
- Sometimes difficult to avoid
- Crowding or tilting of teeth
- Acceptable if less than half of enamel superimposed
- Will miss early carious lesions
- Must show enamel dentinal junction & dentinal half of enamel
7
Q
What receptor sizes are used in bitewings - vertical or horizontal?
A
- Adult – “2” only
- Child – over 10 – “2”
- Child – under 10 – “0” or “1”
8
Q
In collimation is round or rectangular better?
A
Use of rectangular collimation can reduce the dose to the patient by up to 50%
