When restoring implants that are adjacent to natural teeth, dentists and ceramists face many challenges. When the implant replaces a maxillary central incisor, they face one of the most difficult situations in restorative dentistry. Creating gingival symmetry requires evaluation and sometimes modification of osseous levels to support the desired gingival architecture, which necessitates careful communication between the treating dentist and the specialist. Many times, bone grafting and soft-tissue augmentation is required to establish a natural-looking gingival environment. After implant placement, the provisional is used to shape and support the gingiva.

Restoring an implant in the middle of the esthetic zone and between other teeth that are planned for restoration makes it much easier for ceramists to level the playing field at the abutment level. In such instances, the abutment can be matched to the prepared teeth. As we move to complete the treatment with definitive restorations, we are challenged to design a tooth-shaped, tooth-colored abutment that will emerge through the gingiva and appear like the surrounding prepared teeth, without impinging on the vascular supply to the tissue.

If the underlying color of the abutment matches that of the prepared tooth and the restorative thickness is the same, bonded restorations can be used predictably. Because each will have the same underlying color, only the desired shade of the natural teeth needs to be matched.

If laboratory ceramists accomplish this, they can etch the surface of the abutment, then fabricate restorations for all teeth to be restored from the same material. However, when selecting a restorative material to go over an implant, strength and esthetics must be considered. The periodontal ligament that provides some shock absorption in vital, natural teeth is absent with implants, leaving something that is rigidly anchored into bone and able to provide much greater force to the restorative material.

With this in mind and based on the latest research on ceramic materials from New York University College of Dentistry¹, the choice of lithium disilicate as the restorative material and zirconia as the abutment seemed logical for this case (Figs. A and B). NYU research shows that in comparison to several other common restorative options, lithium disilicate is the most robust restorative material tested to date. Also supporting the material selections was knowledge of the esthetic qualities of etched and bonded restorations.

Therefore, a custom-milled zirconia abutment would be fabricated to avoid any grey influence to the gingival tissue surrounding the implant site. To create color and provide an etchable interface with the bonded restoration to be seated over the abutment, IPS e.max Zirliner would be fired to the abutment to bond to the zirconia, and opacious dentin then fired over the Zirliner.

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