#4/#5 RCT, Crown Lengthening, Zirconia Crowns

Background: 25-year-old female patient, who resides in another state, presented with symptomatic irreversible pulpitis on #4 and #5 requiring endodontic root canal therapy, core, and crown.
Endodontic: #5 progressed successfully and uneventfully, however during access and canal exploration, #4 was found to have a 1–2–1 canal morphology, where the single canal bifurcated into two canals within the root and then rejoined apically. Both canals were cleaned, shaped, and obturated without complication. Core build-ups were placed on both teeth #4 and #5 following obturation to restore structural integrity and prepare the teeth for definitive full-coverage restorations.
Procedure time: 2 hours
Fixed prosthetics: Patient returned for definitive restoration two days s/p RCT. Both teeth were prepared for full-coverage zirconia crowns. During preparation of tooth #4, an existing composite restoration was removed on the buccal causing shoulder to extend 5mm subgingivally. Radiographic evaluation and clinical analysis were performed, leading to a diagnosis of altered passive eruption contributing to inadequate clinical crown height. Due to the altered passive eruption, the tooth was still deemed restorable at this point. Patient was consulted of their preferred treatment planning – attempting crown lengthening to restore with crown, or extraction, socket preservation, and implant placement. Patient elected to continue with crown lengthening procedure.
Temporary crowns were fabricated. Due to patient residing out of town, they were not able to return to the clinic for 2 months. Because of this extended interval between visits, particular care was taken to ensure that the provisional restoration had precise marginal adaptation and proper contour to protect the preparation and maintain periodontal health during the interim period. In order to ensure accurate seating of the interim restoration and proper marginal adaptation, a small gingival flap was reflected on tooth #4 to expose the preparation margin. This allowed for clear visualization of the margin and ensured that the provisional crown could be fully seated without impingement on the surrounding tissue.
Delivery and Crown Lengthening: The zirconia crown for tooth #5 was delivered and definitively cemented. Crown lengthening was performed on #4 with careful consideration of the gingival contour of #5 in order to minimize black triangles and avoid recession of tissue on newly cemented crown on #5. Patient is currently healing and will return to the clinic for evaluation of healing and determine the prognosis of #4.