Prosthodontics & Occlusion · patient case question
What is the most appropriate way to address the complaint?
Patient case: Bridge that has debonded after eight years
Patient: Male, 58 years old
Chief Complaint: “My bridge came off in one piece while I was eating.”
Background: Three-unit bridge placed eight years ago. No pain. No systemic disease.
Vital Signs: BP 130/82 mmHg · HR 74 bpm
Findings: The prosthesis has debonded intact. Clinical photographs show markedly OVER-PREPARED abutments — short, heavily tapered, with the margins finishing on existing restorative material rather than on sound tooth. Both abutments are vital, caries-free and periodontally sound. Radiographs show no periapical change.
Show answer and explanation
Correct answer: A. Rebuild the abutments with a bonded core material, then re-prepare them to a correct form for a new bridge
- A. CORRECT. The abutments are SOUND but MIS-SHAPED. Restoring them with a bonded composite or glass ionomer core rebuilds the lost bulk, and re-preparing to a correct form — near-parallel walls, adequate occlusogingival height, and margins on SOUND TOOTH rather than on restorative material — recreates the retention and resistance form that was missing. That is the direct fix for the actual cause of failure.
- B. Posts are for teeth that are ROOT-TREATED and have lost most of the coronal dentine. These abutments are VITAL. Cutting post space into a vital tooth to gain retention devitalises it, removes radicular dentine and invites vertical root fracture.
- C. Extraction discards two vital, caries-free, periodontally sound teeth. It is the most destructive option available and treats a restorative problem surgically.
- D. Re-cementing an over-tapered, short preparation reproduces the failure. Cement compensates for nothing; the geometry is what retains a restoration.
Note: What this item adds is what to DO about it. Note the specific finding that margins sat on RESTORATION rather than tooth — a margin on old restorative material has no reliable seal and no bonding substrate, and it is an independent and often-missed cause of recurrent failure.
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