Hybrid implant-supported restorations bonded to nitride-coated titanium bases: a clinical method to address biologic, functional, and esthetic challenges in the esthetic zone.

Objective: To describe how advancements in digital technologies and materials science provide additional restorative alternatives and material combinations for single- and multiple-unit implant-supported restorations, such as those incorporating the clinical use of nitride-coated titanium bases in combination with the two-piece, CAD/CAM, screw-retained, zirconia-ceramic, hybrid implant-supported restoration concept.

Case presentation: Two partially edentulous patients with missing teeth in the maxillary esthetic zone were treated with a novel technical and restorative concept using the two-piece CAD/CAM screw-retained zirconia-ceramic hybrid-abutment crown concept bonded to nitride-coated titanium bases. Biologic outcomes showed that tissues were maintained healthy with the patients showing an adequate oral hygiene level, no detectable plaque present upon probing, and no bleeding on probing. Esthetic evaluation demonstrated an excellent esthetic outcome and peri-implant soft-tissue integration with adjacent natural teeth and pontic tissue areas, together with posttreatment stability of the gingival zenith position. Neither of the two patients showed technical complications such as screw loosening or porcelain chipping/fracture. Radiographic evaluation revealed a precise fit between nitride-coated titanium bases and the implant connecting interfaces, no marginal bone loss, and stable implant osseointegration. The principal advantages of incorporating nitride-coated titanium bases in implant-supported restorations rely on the favorable esthetic outcomes, improved technical, mechanical, and biologic aspects, as well as the physicochemical characteristics of nitride-coated titanium bases' hard thin film coatings and their positive impact on titanium biocompatibility.

Conclusions: The short-term promising clinical outcomes of the two-piece CAD/CAM screw-retained, zirconia-ceramic hybrid-abutment crown concept bonded to nitride-coated titanium bases, indicate the potential clinical benefits of the described restorative alternative. However, additional in vitro investigations and randomized clinical trials are needed to validate these initial observations, especially those evaluating the two-piece CAD/CAM screw-retained, zirconia-ceramic hybrid-abutment crown bonded to nitride-coated titanium bases when compared to the conventional two-piece hybrid design as well as stock/custom, metal/zirconia/lithium disilicate, screw/cemented implant-supported restorations.