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Zirconia is a ceramic material that is used for constructing prosthetic infrastructures and implant abutments using CAD/CAM techniques. Although good initial mechanical properties are obtained with zirconia that is partially stabilized by yttrium, it may age in a moist environment, compromising such properties and, consequently, the longevity of the restorative work. To optimize the longevity of this material, it is essential that the clinician and laboratory technician understand its mechanical properties and limitations and take specific precautions needed to maintain its mechanical properties and ensure long-term performance especially in implant prosthetics. This article presents a clinical case where these precautions were taken, emphasizing the key surface treatments advocated for zirconia.

Objective This article presents a retrospective analysis of an anterior single crown that showed chipping of the veneering ceramic, the clinical stages of intraoral repair made in composite resin, and fractographic analysis of the causes of failure. Clinical considerations The ceramic chipping occurred in the incisal and labial surfaces of the crown, 1 year after installation. Clinical examination revealed the presence of occlusal interference, which was probably responsible for chipping. Vinyl‐polysiloxane impression was made from the patient, and epoxy replica was produced. The replica was gold coated and inspected under the optical microscopy and scanning electron microscope (SEM) for descriptive fractography. Optical microscopy and SEM images showed that chipping initiated at the incisal edge, where it is possible to note an area of damage accumulation. At the labial surface, multiple arrest lines with their convex sides facing the incisal edge were observed. The fractured area was repaired intraorally with composite resin, and the patient's occlusion was checked and monitored. Conclusion According to the fractographic analysis, occlusal interference was related to ceramic chipping in the incisal edge. Intraoral repair technique with composite resin was indicated for this moderate chipping. Clinical significance Retrieval analysis of chipping ceramic delivers better understanding of the failure origin and could prevent future failures. Intraoral repair is a practical and conservative technique and may be performed in a single clinical session without requiring the removal of prosthesis.

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