Radiograph set-up and legislation Flashcards
What is each couloured ring holder used for?
Blue = anterior periapicals
Yellow = posterior periapicals
Red = bitewings
Green - endo
How do you position the phosphor receptors in the holders?
Locator dot faces away from you at to the ground (align with the slot on the holder) except for bitewings where the dot faces up
What way does the receptor holder go onto the arm?
So that the bite block is in front of where the receptor will lie
The receptor must be sitting within the patients mouth palatally/lingually when the patient is biting down
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If you take an anterior maxillary periapical, how do you then change it to take a mandibular anterior periapical?
Just flip the full holder
How must the radiograph holder be positioned for posterior periapicals?
Need the actual film holder the right orientation (upwards or downwards depending if it maxillary or mandibular)
Need the locator arm to be pointing anteriorally towards the front of the patient
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How should your patient be positioned for bitewings?
Sat upright with head supported
When taking bitewings, how should the film and holder be placed into the patients mouth?
Should be placed with the radiograhic receptor/film as close to the lingual aspect of the lower teeth as possible and approx 3mm infront of the first premolar (or tooth present) to ensure you capture the mesial aspect of this tooth
When might you use a cotton wool roll when taking bitewings?
Only if the patient is missing a tooth in order to help support the bite block
When pressing the exposure button to take a radioraph, what must you do/don’t do?
Must keep pressing the button until you hear the sound and don’t let go too early
What size of phosphor plate do you use for bitewing radiographs?
primary dentition = size 0
mixed and adult dentition = size 2
What size of film receptor is used for anterior periapicals?
size 0
What siz of film receptor is used for posterior periapicals?
size 2
What technique is the technique of choice for periapical and bitewing radiographs?
Paralleling technique
How do you place your patient for periapicals?
Can use frankford plane parallel to the floor but it is not essential for radiographs.
Just make sure that head is supported
How do you position the film holder in the patients mouth for a posterior or anteior periapical?
The aim is the have the receptor following the long axis of the tooth.
Can use cotton wool to aid this positioning
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For OPT’s, what must the pt not be weaing/what do you ask them to take off?
Take off jackets, earrings and any metal dentures etc
Bulky hairstyles such as ponytails and pigtails to be take out
How do you position the patient for an OPT?
Put the pt in the machine and get them to rest their chin on the rest and bite down on the bite block.
Check midline lasor line is on the midline of the face and frankford plane parallel to the floor
Check the canine line and adjust using the buttons if necessary
What are the 2 important pieces of legislation in diagnostic radiology?
IRMER17
IRR17
IRR17 deals with occupational exposure and includes legislation for controlled areas. What are controlled areas and whar should this be for dental x-rays?
Controlled area - a well defined area arounf equipment to lower occupational exposure to radiation
Should be 1.5m from the x-ray tube
What are the 4 roles set out in the IRMER17 that the dentist carries out?
- referrer
- practitioner
- operator
- employer
What are the responsibilities of the practitioner for a radiograph?
- Justification and authorisation of each exam
- Ensure the dose is ALARP (optomised)
- To comply with the Employer’s Procedures
What needs tobe considered to justify an exposure?
- The objectives of the exposure and the efficacy, benefits and risks of available alternative techniques.
- All the potential benefits of carrying out the exposure, including the direct health benefits to the individual and the benefits to society.
- The detriment to the individual.
What is optimisation and what does it involve?
making sure the dose is ALARP
Includes:
- Selecting appropriate investigations
- half panoramic instead of full
- Selecting appropriate equipment
- retangular collimation
- Using appropriate exposure factors
- Ensuring QA is carried out
- Assessing patient dose
- Adherence to diagnostic reference levels
What quality assurance should be carried out to the x-ray receptors?
Exposing x-ray receptor to unattenuated x-ray beam and check the resulting image (should be consistently grey across the entire image)
§ Inspect digital image receptors every 3 months or whenever damage is suspected