The Award contest 2015/ 26 October 2015/

Case 62 | Prosthodontic Award 2015 | Italy

Dr. Gabriele Caruso

A novel approach in prosthetic and transmucosal implant dentistry: the “Vertical Neck®” design

Background	The present case report describes a novel approach in prosthetic and implant dentistry thanks to a new implant design called “Vertical Neck®”, characterized by a transmucosal conical segment without prosthetic shoulder and an Implant-Abutment Interface (Microgap [MG]) located more than 2 mm above the alveolar crest close to the gingival margin.
Aim/Hypothesis	This approach allows to define a customized, scalloped-designed restorative finishing line combined with an anatomical emergence profile, well defined prosthetic margins location of the clinical crown, with the only Microgap being located within the periimplant gingival sulcus and in a more biocompatible fashion. This step-by-step documentation describes the clinical procedure on a 18-year and 7-months old male patient and in a single tooth edentulous site of the anterior maxilla (21).
Material and Method	The “Vertical Neck®” implant (Biotype Implant System®, Cagliari / Italy) exhibited a cylindrical full-body screw shape design with a tapered apical portion made from commercially-pure grade 4 titanium. The regular neck inner implant diameter with the threaded part was 4.8 mm. The transmucosal conical segment of the “Vertical Neck®” implant had two outer diameters: the apical one measured 4.8 mm, whereas the coronal one was 4.1 mm in diameter. The upper portion of the implant consisted of a 2.5 mm relatively smooth, machined titanium surface in length, with the conical part measuring 1.9 mm in length (‘preabutment’). The rough part of the implant consisted of a sandblasted, large-grit and HCl/H2SO4 dual acid-etched surface with a length of 13 mm and a self-tapping thread design. In addition, the most coronal section was modified with a microgroove texture. In addition, the screw-retained abutment connected to the external hex design of the one-piece soft tissue level implant body design. A male patient 18 years and 7 months y.o. lost a central left incisor (tooth 21) due to dislocation after a motorcycle accident. He came to our practice in order to replace the missing tooth with an implant. Both the dental and medical anamnesis were negative, he did not have a periodontitis and he is not a smoker. Treatment sequence: • Patient’s data collection, signed informed consent. • Periapical radiograph of the site 21, using X-ray ring to obtain parallel technique. • Surgery: implant (4,8 x 13 mm) positioning in site 21 and simultaneous little G.B.R. technique. • Delivery of the provisional crown, made with CAD/CAM technique. • Delivery of the definitive crown, made with CAD/CAM technique. • Periapical radiograph of the left central incisor, using X-ray ring to obtain parallel technique, at 30 months of loading.
Results	In this clinical case we were able to achieve the entire interproximal papilla in both sites, mesial and distal. We supposed that the emergence profiles of provisional and definitive crowns were able to support and keep the gingiva in a new position, up to 30 months of loading.
Conclusions and clinical implications	The aesthetic of the periimplant gingiva can be enhanced through modification of the edge, shape and depth and the prosthetic restoration’s emergence profile. In order to put this technique in practice, it is necessary to utilize a conical transmucosal implant segment (Vertical Neck, Biotype Implant System) which allows modifications on prosthetic restoration. These modifications imply clinical meaningful effects. Nonetheless, further studies are required to build a link between prosthetic margins and emergence profile, requirements of soft tissue and periimplant gingiva ‘s adaptation. Further studies should also establish a clinical protocol about prosthetic margin’s location and emergence profile’s guidelines.