TOPIC: QUALITY CONTROL IN DENTAL RADIOGRAPHY
🌟 IMPORTANT POINTS TO REMEMBER
🔹Quality control: It is the specific measure for ensuring and verifying the quality of the radiograph taken.
🔹Quality assurance: The arrangement to ensure that the quality control procedures are effective, leading to relevant changes and improvement.
🔹Quality audit: It is the process of supervision of quality control and quality assurance mechanisms for satisfactory and effective working.
🔹Films reject an alysis: It is a simple method of identifying all film faults and sources of error and record to maintain the nature and cause of rejected radiograph
🔹Calibration of X-ray machine: It is done for X-ray output, collimator alignment, beam energy, timer, tube head stabilization, and focal spot size.
🔹Tube rating- electrical rating: It tells us the maximum combinations of kVp, mA, and time that may be used.
🔹It may be classified as electrical and thermal
🔹Thermal rating: It is the number of times you can take a radiograph at a stretch without burn-out of anode.
🔹Duty cycle: It relates to how frequently successive exposures can be made.
🔹Spinning top test for timer accuracy: This test is used for measuring the number of X-ray pulses, the machine produces
🔹Pinhole camera technique for focal spot assessment: A piece of lead of 1 mm in thickness is placed over the collimator opening in the base of the cone. A small hole not larger than 0.5 mm in diameter is made in the centre of the lead
🔹Fresh film: It appears clearer with a blue tint which means film is properly stored and protected.
🔹Fogged film: It appears fogged, meaning that the film has expired, improperly stored or exposed to radiation.
🔹Regular checks of light tightness: Load a cassette with an unexposed film and place the cassette on a window shelf in the daylight for a few minutes. Process the film normally and any ingress of light will fog the film
🔹Step-wedge film: It is a device with a small, graduated increase in the thickness of its material.
🔹Step-wedge radiograph: Take a radiograph of a step wedge using known exposure factors.
🔹Reference radiograph: It is the one that is processed under ideal conditions and is used to compare film densities of radiographs processed daily.
🔹Types of filter: The type of filter which should be compatible with the colour sensitivity of the film used, i.e. blue, green, ultraviolet.
🔹Condition of filter: The scratched filter should be replaced.
🔹Watt of bulb: It should be not more than 25 W.
🔹Distance from work area: The distance from the work surface should not be more than 4 ft.
📌 Aims of Quality Assurance Programme
- High standard radiograph: It should be aimed to produce diagnostic radiographs of consistently high standards.
- Retake radiograph: To reduce the repetition of the radiograph.
- Source of error: To determine all sources of error to allow their correction.
- Efficiency: To increase the efficiency of the machine.
- Cost: To reduce costs to the patient.
- Reduction of dose: To reduce the radiation dose to the patient and staff.
📌 To monitor fixing following tests are carried out:
- Preparation of film: Unwrap one film and immediately place it in the fixer solution. Check the time taken for clearing.
- Fast clearing: If the film clears in 2 min, the fixer is of adequate strength.
- Slow clearing: If the film is not completely cleared after 2 min, then fixer strength is not adequate
📌 MULTIPLE CHOICE QUESTIONS (MCQs)
💡Which amongst the following should be measured to ensure sufficient energy for film exposure?
- HVL of beam
- FVL of beam
- CVL of beam
- All the above.
Answer: 1
💡Process of supervision of quality control and quality assurance mechanisms is
- Quality supervision
- Quality monitoring
- Quality audit
- Quality management.
Answer : 3
💡 Focal spot size gets enlarged with
- Increased heat
- Decreased heat
- Not related to heat
- None
Answer: 3
💡The maximum load that may be applied on the tube which may not cause any breakdown or damage to the tube is termed as
- Tube rating
- Tube loading
- Maximum tube concentration
- None of the above
Answer: 1
💡Spinning top test is a test for
- Amount of load
- Timer accuracy
- Radiation output
- All the above
Answer : 2
💡 Density and radiation output are
- Directly proportional
- Inversely proportional
- No relation
- None
Answer: 1
💡In the pin-hole camera technique for focal spot assessment, the thickness of lead is
- 1 mm
- 2 mm
- 3 mm
- 4 mm
Answer: 1
💡Darkroom efficacy is tested by
- Coin test
- Penny test
- Both the above
- None
Answer: 3
💡 The optimal temperature for checking developer in automatic processing is
- 28°C
- 30°C
- 24°C
- 19°C
Answer: 1
💡 A film with a small gradual increase in the thickness of its material is known as
- Step-down film
- Step-striped film
- Step-wedge film
- None
Answer : 3