Radiographs Flashcards
Name 2 regulations in relation to radiographs
- IRR - Ionising Radiation Regulations
2. IRMER - Ionising Radiation Medical Exposure Regulations
What is the major difference between IRR and IRMER?
IRR is in relation to staff and IRMER is in relation to patients
Describe 4 parts of a selection criteria before taking radiographs
- Be clear what you want radiograph to show
- Unnecessary exposure must be avoided
- Not acceptable to take radiographs because patient hasn’t had any in a while
- Consider types of radiographs available to reduce radiation dose
Name 3 components of taking a radiographs
- Justification
- Optimisation
- Evaluation
Describe justification of a radiograph
- Each must be justified as showing sufficient benefit
- Good practice but no legal requirement
- When referring, the referrer must supply details of radiograph history
Give an example of a justification for bitewings
Interproximal caries
Give an example of a justification for IOPAs
Apical pathology of the tooth
What is the key mnemonic for optimisation of a radiograph?
ALARP - As Low As Reasonably Practicable
Name 3 ways to ensure radiation is kept as low as reasonable practicable
- Ensure equipment is calibrated correctly, serviced etc
- Maintain skills
- Maintain knowledge
Describe clinical evaluation of radiographs
- All radiographs must be reported on
- This includes any radiographs which quality is too poor to be diagnostically valuable
What is quality assurance of a radiograph?
It is essential each radiograph is graded and information is used so deficiencies in systems can be recognised
Describe the grading process of radiographs
- Excellent - Over 70% of radiographs taken
- Diagnostically acceptable - No more than 20%
- Unacceptable - No more than 10%
Name 3 most often used radiographs in restorative dentistry
- Bitewing
- Periapical (IOPAs)
- Panoramic Tomography (OPT)
What is the main indication for bitewing radiographs?
- Detection of dental caries
- Initial periodontal assessment
- Radiographic assessment of restorations
Describe carious lesions visible on radiographs
Detectable when there is enough demineralization to allow lesion to be differentiated from enamel and dentine
Describe the frequency of bitewings taken for different types of patients
High risk - 6 months
Moderate risk - 12 months
Low risk - 24 months
Low risk children - 12 - 18 months
Name 2 ways in which radiographs can be used to assess restorations
- Assessment of ledges and overhangs
2. Marginal fit of cast restorations
Describe a good technique to aid optimisation
A simple film holder will help position the film packet and facilitate positioning of the x-ray tubehead
Describe 2 potential problems if holders are not used taking radiographs
- Overlapping
2. Coning off
Describe 2 things to note when radiographically assessing radiolucent areas
- Caries v Burnout
2. Size of pulp chamber
Describe 3 things to note when radiographically assessing radio-opaqueareas
- Restorations, calculus and artefacts
- Presence of root filling material
- Presence of posts and pins
Name 2 misleading shadows on a radiograph
- Cervical burn-out
2. Radiopaque zone beneath amalgam restorations
What is cervical burnout?
Artefactual phenomenon created by anatomy of teeth and variable penetration of x-ray beam
Describe 3 characteristics of burnout
- Located at neck of teeth
- Triangular in shape
- All teeth in radiograph usually affected
Describe radiopaque zones beneath amalgam restorations
- Under restorations ions are released into demineralized dentine
- Radiopacity of zone may make normal dentine appear darker
What are the 6 main indications for taking IOPAs?
- Detection of periapical infection
- Assessment prior to crown of bridgework
- Localised periodontal assessment
- Bone loss
- Before commencing, during and assessing endodontics
- Assessment of operative appraisal of apical surgery
Describe x-ray tube positioning
Should be positioned so that the beam meets the tooth and film at right angles in both vertical and horizontal planes
Describe 2 potential problems with IOPAs if holders are positioned incorrectly
- Foreshortening
2. Elongation
Describe 3 advantages of OPTs
- Shows all teeth and supporting structures on one film
- Technique is reasonably simple
- Radiation dose is relatively low
Describe 3 main restorative indications of OPTs
- Overview of dental caries
- Overview of periodontal disease
- Implant placement assessment
Name 4 non-restorative indications of OPTs
- Orthodontic assessment
- Establish size of jaw lesions
- Fractures of the mandible
- Assessment of third molars
