Objectives: The study aimed to evaluate bone formation following maxillary sinus augmentation using bovine bone substitute material Bio-Oss[tm] and to determine the long-term success rate, using radiographic images of implants installed after sinus lifting procedure. Methods: Between January 2000 and October 2015, a total of 147 implants were placed in 64patients (24 men and 40 women), aged 34–87 years (meaan 57.39 years), in whom sinus lifting technique was performed on edentulous ridge bone (with 1–4mm residual bone height). Long-term evaluation involved comparing radiographic images at various time points from 99 cases of sinus floor elevation in the 64 patients, according to the technique described by Tatum (1986). Dental implants were inserted after 8 months of graft healing, and left submerged for 3 months. They were then loaded with provisional acrylic prostheses, which were replaced by definitive fixed metal–ceramic prostheses and followed for over 5 years of functional loading. All patients visited the clinic at 1 week, 2 months and 8 months in the first postoperative year, then at 1 year, 2 years, 5 years, 10 years and 15 years[ok?] thereafter, for clinical and radiographic examinations of the sinuses and implants, including CT imaging. Results: Twelve of the 147 implants were lost, giving a cumulative survival rate (CSR) of 91.83%. All lost implants were substituted and all patients who were followed had fixed prostheses functioning after 5 years of loading. Conclusion: This study suggests that the installation of implants after a sinus lift procedure combined with deproteinised bovine bone substitute material (Bio-Oss[tm]) graft in cases with pneumatisation of the posterior maxilla have predictable high survival rates. The procedure is a reliable option for the placement of implant-supported prostheses in patients with increased pneumatisation of the maxillary sinus and atrophic alveolar bone.

Objectives: The study aimed to fabricate a novel bone-regenerative scaffold based on systematic combination of porous organic–inorganic hybrid scaffolds and recombinant human parathyroid hormone (rhPTH). Methods: The hybrid scaffold was fabricatedby immobilisation of polyphosphate-functionalised nano-hydroxyapatite (PP-n-HAp) on the surface of porous poly(l)-lactic acid (PLLA) scaffolds. This was followed by rhPTH loading on the polyphosphates of n-HAp surfaces. The surface polyphosphate functionalities of PP-n-HAp enabled stable chemical immobilisation of n-Hap on the amine-treated pore surface of the PLGA scaffolds. RhPTH with a positive charge was bound at a high efficiency of 98.1–99.5% onto the anionic polyphosphates of PP-n-HAp immobilised on PLLA surfaces and was released sustainably for up to 50 days. The release rate was manipulated by adjusting the amount of loaded rhPTH, and the release data were moderately fitted to the Higuchi’s diffusion model. Results: Immobilisation of PP-n-Hap was performed with a 1-ethyl-3-(3-(dimethylamino)propyl)carbodiimide (EDC)-mediated coupling reaction between the acidic PP groups and the primary amine groups on the surface of amine-functionalised PLLA scaffolds. They have a mean surface pore size of 110±10μm. Even after PP-n-HAp immobilisation, the initial interconnected pore structure and pore diameter were maintained. The pore size of PP-n-HAp-PLLA scaffolds may allow the spaces enough forthe growth of bone-forming cells. Thermogravimetric analysis (TGA) showed that the amount of immobilised n-HAp on the pore surface of PLLA scaffolds was 11.3 wt%. The dose-dependent sustained release patterns of rhPTH from PP-n-HAp-PLLA scaffolds were confirmed by a release profile. Four types of scaffolds were tested in rabbit calvaria defect models: (i) PLLA only, (ii) PP-n-HAp-PLLA, (iii) rhPTH (2mg) loaded PP-n-HAp-PLLA, and (iv) rhPTH (10mg) loaded PPn-HAp-PLLA. After 5 weeks, rhPTH-loaded PP-n-HAp-PLLA (with 2mg and 10mg rhPTH) displayed higher bone growth than the control group (PLLA only). Conclusion: We described the fabrication of porous PLLA scaffolds with rhPTH-releasing PP-n-HAp for bone regeneration. This hybrid scaffold was prepared by PP-n-HAp immobilisation onto the PLLA scaffolds, followed by the sequential rhPTH loading on PP-n-HAp. RhPTH was incorporated with high efficiency, and the sustained release of rhPTH from the hybrid scaffolds was observed for up to 50 days. In the animal experiment, we showed that the pore surface of the PLLA scaffolds had a synergistic bone-forming effect, not only due to surface-exposed osteoconductive n-HAp but also due to the sustained release of rhPTH. This bone-regenerative hybrid scaffold may find broad applications as a bone generation material.

Gliederung - Schneidekantenaufbau am Zahn 11 - Skizze vor der Verbreiterung der Frontzähne - Applikation und Ausformung der Matrize zur Zahnverbreiterung - Applikation des fließfähigen Komposites und Spreizen mit kleinem Heidemannspatel zur Herstellung eines festen und flächenförmigen Approximalkontaktes - Applikation von Dentin- und Schmelzkomposit - Ausarbeitung und Formgebung mit Positionierung der lateralen Kantenlinien und Gestaltung des interinzisalen Dreiecks - Herstellung eines unsichtbaren Überganges, Komposit - Schmelz mit dem Skalpell Nr. 15 - Politur Materialliste: Adhäsiv: - Optibond Fl (Kerr) Komposit: Enamel HFO (Micerium) - Dentinmassen UD4, UD3,5 und UD3 - Schmelzmassen GE2 - Opaleszenzmasse OBN Flowable Komposit: - Tetric Flow A4 (Vivadent) Provisorisches Komposit zur Ausformung der Matrize: - SystepOnlay (Vivadent)