Deep caries with a pinpoint exposure in a bruxing adult molar
A 44-year-old man presents with discomfort in tooth 36 on chewing and a 6-day history of pain provoked by cold drinks that lingers about 10 seconds after the stimulus is removed. There has been no spontaneous or nocturnal pain, no swelling, and no tenderness to percussion. Probing depths are 3 mm or less all around and the tooth is not mobile. A periapical radiograph shows deep occlusal caries approaching the pulp, an intact lamina dura and no periapical radiolucency. He grinds at night and wears a hard occlusal splint that he has broken twice. After rubber dam isolation and complete removal of the peripheral caries, a 1.5 mm pulp exposure appears with brisk bleeding that is controlled with 2.5% sodium hypochlorite in about 4 minutes. He is medically healthy, takes no medication, and asks whether the tooth can be saved without a root canal and whether he can simply have 'a filling'.
1. State your pulpal and apical diagnosis before treatment and explain exactly which findings drive each part of the diagnosis.
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Pulpal diagnosis: symptomatic irreversible pulpitis. The discriminating feature is the character of the cold response - pain that lingers about 10 seconds after the stimulus is removed indicates a pulp that can no longer return to baseline, which places it beyond reversible pulpitis regardless of the absence of spontaneous pain. The presence of a deep carious lesion reaching the pulp on the radiograph is consistent with this, but radiographic depth alone never establishes the diagnosis.
Apical diagnosis: normal apical tissues. There is no tenderness to percussion, no swelling, no sinus tract and no periapical radiolucency, and the lamina dura is intact. This matters because it means the canal system has not yet become infected at the apical level, and it changes both prognosis and the urgency of treatment.
Supporting findings: probing depths of 3 mm or less exclude a periodontal or endodontic-periodontal lesion as a source of the chewing discomfort, and normal mobility again points away from apical pathosis. The chewing discomfort in a bruxer is most likely related to the lost marginal ridge and the carious lesion rather than to apical inflammation, and it will resolve with a properly designed restoration. Recording all three components - pulp, apical tissues, and the restorative/occlusal problem - protects you from treating only one of them.
2. Given the intraoperative exposure and the bleeding pattern, choose between full pulpotomy and complete root canal treatment. Justify your choice and explain what would change your mind.
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The bleeding that stops within 4 minutes with sodium hypochlorite indicates that the coronal pulp is still vital and that haemostasis is achievable - the classic prerequisite for a full pulpotomy with a hydraulic calcium silicate cement. In a younger patient, or in a tooth with an open apex, I would push harder toward pulpotomy. Here the patient is 44 with a mature, closed apex and a molar that is already structurally compromised and subject to nocturnal bruxism. In mature teeth with symptomatic irreversible pulpitis, full pulpotomy series report short-term success in roughly the 80–90% range, but the evidence base beyond a few years is thin and success falls with time, whereas root canal treatment in a tooth with normal apical tissues has a well-documented long-term prognosis above 90%.
I would therefore recommend complete root canal treatment, and explain honestly that a full pulpotomy is a reasonable alternative if he prefers to retain vital tissue, provided he accepts a higher chance of later pulp breakdown and the need for close radiographic review. Factors that would move me to pulpotomy: an exposure under 2 mm with clean haemostasis, a patient unwilling to accept root canal treatment, or a strategic tooth where root canal treatment is technically compromised. Factors that would rule pulpotomy out: uncontrolled bleeding, necrotic tissue in the canal orifices, or a periapical lesion.
3. Plan the definitive restoration and the review schedule, taking his bruxism into account.
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This is a structurally compromised first molar in a bruxer with a history of splint breakage, so a direct intracoronal restoration is not acceptable definitive care. Cuspal coverage is required: after cleaning and shaping, I would place an immediate dentine seal and a provisional restoration, confirm that the tooth is asymptomatic and that the canals are healing, and then prepare for a full-coverage or onlay-type restoration with a minimum of 1.5 mm of occlusal material on the functional cusps.
Retention is obtained from the remaining coronal walls, not from a post - a post does not strengthen a root and adds perforation and fracture risk. Core build-up should end at least 2 mm above the gingival margin where possible.
Occlusally, I would check for interferences in lateral excursions and reduce the load on this tooth, and I would remake his occlusal splint with a hard, flat-plane design with even contacts and canine guidance. Review at 6 and 12 months with periapical radiographs to confirm periapical healing, then annually. He should be warned that a root-treated molar with this amount of lost structure, under bruxism, carries a real risk of cusp or root fracture, and that the splint is part of the treatment, not an optional extra.