Failing MOD Restoration on a First Molar with Reversible Pulpitis Signs
A 42-year-old woman presents with a 3-day history of sharp pain on biting and sensitivity to cold on tooth 46. The pain resolves within seconds of removing the stimulus, and she has no spontaneous or nocturnal pain. Examination reveals a large amalgam MOD restoration with a fractured distal marginal ridge, a 4 mm probing depth on the distal aspect, and no mobility. Radiographs show the restoration approaching the pulp within 1 mm on the distal, a normal periodontal ligament space, and no periapical radiolucency. The tooth is vital and responds to cold with a brief, exaggerated response. The patient is systemically healthy, takes no medications, and reports no parafunctional habits. She is anxious and requests a single-visit solution if possible.
1. What is your pulpal and periapical diagnosis, and what is the most appropriate definitive treatment plan? Justify why replacement rather than repair is indicated.
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Diagnosis: Reversible pulpitis with symptomatic apical periodontitis is unlikely given the brief nature of the pain; the biting pain is more consistent with a cracked cusp or marginal ridge fracture. Normal periapex.
Reasoning:
- Pain that resolves within seconds of cold removal = reversible pulpitis (AAE terminology). No spontaneous/nocturnal pain excludes irreversible pulpitis.
- Biting pain localized to a fractured marginal ridge suggests structural failure, not pulpal pathology.
- The 4 mm distal pocket is likely pseudopocketing from the overhanging/fractured margin; confirm with probing after removal.
Plan: Replace the restoration with a bonded indirect or direct restoration (e.g., onlay or composite) that restores cuspal coverage on the weakened distal marginal ridge. Repair is not indicated because the fracture involves a functional cusp and the remaining tooth structure is compromised. If pulp exposure occurs during preparation and hemostasis is achieved, direct pulp capping may be considered; otherwise, root canal treatment followed by cuspal coverage.
Why not endodontics now: Vital, reversibly inflamed pulp does not warrant RCT. Monitor post-operatively.
2. The patient is anxious and asks for a single visit. How would you sequence the appointment, and what would you tell her about prognosis and the possibility of needing endodontic treatment later?
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Sequencing (single visit):
- Anesthesia and rubber dam isolation.
- Remove the existing restoration and fractured fragment; evaluate remaining tooth structure and pulp status.
- If pulp is exposed and bleeding is controlled with sodium hypochlorite or ferric sulfate, consider direct pulp cap with bioactive material; otherwise proceed to RCT.
- Build up with a bonded core; prepare for cuspal coverage (onlay or crown).
- Verify occlusion and margins; take final impression or scan if indirect.
Patient communication:
- Explain that the brief cold sensitivity and biting pain are consistent with a damaged filling and a cracked cusp, not an infected nerve.
- Prognosis is good if the tooth can be restored with cuspal coverage; however, the deep distal caries/restoration margin means the pulp is at risk.
- Warn that if she develops spontaneous or night pain, or if the pulp is exposed and cannot be sealed, root canal treatment will be needed.
- Discuss that a 4 mm pocket may resolve after the overhang is removed; if it persists, periodontal evaluation is warranted.
Anxiety management: Discuss sedation options, explain each step, and use a stop signal.