Radiograph retake on a gagging patient
A 41-year-old woman arrives for a recall appointment. She reports that previous radiographs made her gag and that she has a strong gag reflex. The dentist has prescribed a four-image bitewing survey plus two periapical views of the maxillary molars. The patient is not pregnant and has no known medical contraindications. On the first attempt, the size-2 sensor is placed and the patient gags before the exposure; she pushes the sensor away with her tongue and sits up. She is visibly anxious and says, 'I don't think I can do this.' The dentist is working on another patient and has asked you to complete the prescribed series. The patient's mouth is moist, and the sensor cable is pulling slightly on the corner of her mouth.
1. What should you do before making another exposure attempt, and why?
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Stop and address the patient's anxiety and technique before exposing again. A gag reflex is a protective response, and forcing the sensor will worsen it and may result in a nondiagnostic image and additional retakes, which increases dose. Reassure the patient, explain each step in advance, and obtain her cooperation. Reduce tactile triggers: use a smaller receptor if available, warm the sensor, and place it without touching the soft palate or the posterior tongue. Have the patient breathe through her nose, and suggest a distraction such as lifting her legs or counting. Position the sensor with a holder rather than finger retention, and check that the cable is not pulling on the corner of the mouth, since that traction can trigger retching. Do not expose until the patient signals readiness and the receptor is stable and correctly positioned.
2. The first acceptable image shows the distal of the maxillary second premolar open and the contact with the first molar overlapped. How do you correct the technique for the remaining bitewings?
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The overlap indicates incorrect horizontal angulation, not a patient problem. The central ray must pass perpendicular to the curvature of the arch and through the interproximal contacts being recorded. For the maxillary bitewing, adjust the aiming ring so the beam is directed slightly downward, aiming through the contact between the second premolar and first molar, and confirm the receptor is parallel to the teeth with the holder. Ask the patient to close gently on the bite block and keep the tongue away from the palate. Recheck that the sensor edge covers the distal of the canine or the required teeth. If the contact still overlaps, reposition rather than exposing repeatedly. Also verify that the receptor is not bent, since bending can distort the image.
3. The patient asks why six images are needed when she 'just had x-rays.' How do you respond, and what documentation should accompany the retakes?
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Explain that the number and type of images are selected by the dentist based on the clinical findings and the diagnostic information needed, such as caries detection, bone levels, and the periapical status of the molars, and that prior images may not cover the same areas or may be out of date. Avoid promising that fewer images would be fine. Document the prescribed series, the number of exposures made, any retakes with the reason, and the patient's reported gag reflex and the accommodations used. Retakes must be justified in the record because they add dose. Confirm the machine settings and receptor position before each exposure so that no image is repeated unnecessarily.