A pregnant patient with irreversible pulpitis and a request for 'no X-rays'
A 29-year-old woman who is 11 weeks pregnant attends with severe spontaneous pain in the lower right first molar (46) for 3 days. The tooth has deep distal caries, a positive cold test that lingers, and no percussion tenderness or swelling. You diagnose irreversible pulpitis and plan root canal treatment. She is anxious about radiation and asks you to treat without any radiograph. She has read that dental X-rays can harm the baby. You have digital intraoral equipment, rectangular collimation, and lead aprons. She has no other medical history and takes only folic acid. The tooth is restorable, and she wants to keep it. You need a working length and to check the periapical tissues before starting. The practice has an OPG and a CBCT unit, but no on-site specialist.
1. How would you justify a periapical radiograph in this patient, and how would you explain the risk?
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Justification is procedure-specific: without a radiograph, working length and periapical status are uncertain, which increases the risk of inadequate treatment, repeated visits, and further intervention. The benefit of a single, well-collimated digital periapical radiograph outweighs the very small radiation risk. Dental radiography is not a reason to withhold necessary treatment.
Explain that the dose is very low and that the beam is directed at the jaw, not the pelvis. Use a lead apron over the abdomen and pelvis, rectangular collimation, digital receptors, and good technique to avoid repeats. Do not use the pregnancy as a reason for a blanket refusal, and do not promise zero risk. Obtain and record informed consent after that discussion.
2. Would you use CBCT? Why or why not?
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No, not as a first-line investigation here. A periapical radiograph should answer the immediate questions: working length, root morphology, and periapical status. CBCT carries a higher dose and is justified only when conventional imaging is insufficient and the result will change management. This is a routine irreversible pulpitis case with a restorable tooth and no complex anatomy suggested.
If the tooth proves difficult, if there is suspected root fracture or unusual anatomy, or if endodontic treatment fails, refer for a justified CBCT rather than scanning by default. Record the reason for choosing PA over CBCT. The ALARA principle is not just about dose reduction; it is about not doing an examination that is not needed.
3. What would you record and what safety net would you give?
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Record the pregnancy, the clinical diagnosis, the justification for radiography, the consent discussion, the dose-reduction measures, and the number of exposures. Note that CBCT was considered and not indicated. Record the working length and treatment plan.
Give a safety net: warning signs such as increasing pain, swelling, fever, or inability to open the mouth; an emergency contact; and a review appointment. Explain that pregnancy does not prevent local anaesthesia or endodontic treatment, and that pain and infection should be managed. If she remains anxious, offer to speak with her obstetric clinician, but do not delay urgent care unnecessarily.