Flashcards in Oral Cavity Deck (310)
Explain the effect of age on radiation risk
Children much more at risk due as cells are dividing, growing
Older people have negligible risk as won't see effect
What is the main justification for radiographs?
Benefit to patient must outweigh detriment
What are the 5 justifications of radiographs?
1. Findings and availability of previous X-rays
2. Alternatives: little or no radiation w/ same objective
3. Total benefit to patient
4. Risk: radiation risk associated w/ examination
5. Objectives in relation to history and examination
Describe the optimisation and limitation of radiographs
Optimisation: patient doses should be red. to as low as reasonably practicable
Limitation: equivalent dose to patient should not exceed limits recommended by ICRP
What are the 4 areas where radiation dose can be reduced?
2. Clinical decision
3. Practical technique
4. Diagnostic interpretation
What are the 5 equipment factors that can red. dose?
1. Focus to skin distance: 15-20cm
2. Rectification: AC-DC, more photons, lower dose
3. Aluminium filtration: remove low energy photons
4. Rectangular collimation: rectangular sensor to rectangular film
5. Film and sensors: digital vs conventional
Describe conventional and digital radiographs films
Conventional: can't be exposed to light, long time to develop, develop in dark room
Indirect digital: phosphorus plate, quicker, use reader to develop
Direct: charge-coupled device, instant, no lag time, special holders, bulkier
Digital red. dose by 50% but may require more retakes (less careful as so quick and easy)
Latitude (range of exposures image will be captured) wider for digital which could inc. dose as high quality images obtained at extremes thus don't check everything working
What are the 6 remits for radiographs?
1. Caries diagnosis
2. Developing dentition
4. Periodontal assessment
5. Implant dentistry
6. Good practice
What are the 3 practical technique factors for taking radiographs?
1. Aligning tube w/ film
2. Lead aprons: no justification, discouraged for panoramics
3. Pregnancy: justification, optimisation, delay, lead for physiological reasons