In recent years, single anterior implants have become a predictable treatment option when a tooth is missing or in need for extraction. The situation becomes more challenging when a veneer restoration has to be fabricated next to an anterior implant crown. Blending the color and especially the translucency of a veneer restoration with an adjacent crown is always difficult.
To match both restora- tions in a simple manner, a screw-retained implant crown is the restoration of choice to allow shade matching of the zirconia abutment to the color of the prepared veneer abut- ment tooth. When the shade of the zirconia abutment is the same as the shade of the abutment tooth, the dental tech- nician can build up both restorations in the same manner and create an optimal result. Key details are explained and depicted with two select clinical cases.
• Initial situation reveals a vertical and horizontal ridge defect in the area of the right central incisor.
• Implant placement with a Slim healing abutment in a one-stage surgery.
• Subepithelial connective tissue graft (CTG) was harvested from the tuberosity and sutured crestally on the ridge to minimize the tissue defect.
Restorations: Screw-retained implant restoration to replace maxillary right central incisor and porcelain laminate veneer on left central incisor.
Materials used: Maxillary right central incisor—white color ZR NobelProcera, bonded with HO0 Multilink Hybrid abutment (Ivoclar Vivadent) to titanium abutment, engaging. Maxillary left central incisor—laminate veneer bonded with translucent resin cement G-CEM LinkAce (GC). Creation ZI-CT porcelain used for both restorations.
Restorations: Screw-retained implant restoration to replace maxillary left central incisor and porcelain laminate veneer restoration on the right central incisor.
Materials used: Maxillary left central incisor—white color ZR NobelProcera, with ASC abutment, 20-degree angulation. Maxillary right central incisor—feldspathic veneer cemented with translucent resin cement G-CEM LinkAce (GC). Creation ZI-CT porcelain used for both restorations.
In all of our patients restored with a single implant, the teeth adjacent to the implant are splinted to avoid continuous extrusion of the teeth, especially in Class II malocclusion cases.
Benefits of this Protocol:
• Designing a screw-retained implant restoration allows the clinician to try in the zirconia abutment and match it to the shade of the natural abutment tooth after veneer preparation. The angulated screw channel (ASC, Nobel Biocare) can be angulated more than 25 degrees and thereby increases the possibility to fabricate screw- retained implant restorations by approximately 40%.
• The bonding procedure is simplified since only one ve- neer is bonded. The screw-retained restoration veneer is built up in the same manner as the laminate veneer.
• There is improved accuracy and adjustment of the ve- neer cementation as well as the interproximal contacts between the veneer and the implant restoration. The veneer is bonded first to ensure optimal marginal adaptation. Then, the screw-retained implant restoration is torqued down and interproximal contact areas are ad- justed until ideal pressure is achieved.
• The shade match between both materials is better since the veneer porcelain layering is performed in the same manner on a verified base color abutment. The intention is always to cement the veneer with a translucent ce- ment to not interfere with the overall value of the restoration and match of both restorations.
One disadvantage of this technique is that a second try-in appointment is necessary to verify the base shade of the prepared veneer and the zirconia abutment color to achieve the results illustrated in the cases presented.
Để truy cập toàn bộ bài viết, xin vui lòng xem thêm tại đây