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Sauerbier S.,Universitatsklinik For Zahn Mund Und Kieferheilkunde | Stricker A.,Universitatsklinik For Zahn Mund Und Kieferheilkunde | Kuschnierz J.,Universitatsklinik For Zahn Mund Und Kieferheilkunde | Buhler F.,Universitatsklinik For Zahn Mund Und Kieferheilkunde | And 5 more authors.
Tissue Engineering - Part C: Methods | Year: 2010

Objective: To compare new bone formation in maxillary sinus augmentation procedures using biomaterial associated with mesenchymal stem cells (MSCs) separated by two different isolation methods. Background: In regenerative medicine open cell concentration systems are only allowed for clinical application under good manufacturing practice conditions. Methods: Mononuclear cells, including MSCs, were concentrated with either the synthetic poylsaccharid (FICOLL) method (classic open system-control group, n=6 sinus) or the bone marrow aspirate concentrate (BMAC) method (closed system-test group, n=12 sinus) and transplanted in combination with biomaterial. A sample of the cells was characterized by their ability to differentiate. After 4.1 months (SD±1.0) bone biopsies were obtained and analyzed. Results: The new bone formation in the BMAC group was 19.9% (90% confidence interval [CI], 10.9-29), and in the FICOLL group was 15.5% (90% CI, 8.6-22.4). The 4.4% difference was not significant (90% CI,-4.6-13.5; p=0.39). MSCs could be differentiated into osteogenic, chondrogenic, and adipogenic lineages. Conclusion: MSCs harvested from bone marrow aspirate in combination with bovine bone matrix particles can form lamellar bone and provide a reliable base for dental implants. The closed BMAC system is suited to substitute the open FICOLL system in bone regeneration procedures. © 2010, Mary Ann Liebert, Inc. Source


Gutwald R.,Albert Ludwigs University of Freiburg | Haberstroh J.,University Hospital Freiburg | Stricker A.,Albert Ludwigs University of Freiburg | Ruther E.,Albert Ludwigs University of Freiburg | And 10 more authors.
Journal of Cranio-Maxillofacial Surgery | Year: 2010

Background: Several studies have reported certain bone morphogenic proteins (BMPs) to have positive effects on bone generation. Although some investigators have studied the effects of human recombinant BMP (rhBMP-2) in sinus augmentation in sheep, none of these studies looked at the placement of implants at the time of sinus augmentation. Furthermore, no literature could be found to report on the impact that different implant systems, as well as the positioning of the implants had on bone formation if rhBMP-2 was utilized in sinus-lift procedures. Purpose: The aim of this study was to compare sinus augmentation with rhBMP-2 on a poly-d, l-lactic-co-glycolic acid gelatine (PLPG) sponge with sinus augmentation with autologous pelvic cancellous bone in the maxillary sinus during the placement of different dental implants. Materials and methods: Nine adult female sheep were submitted to bilateral sinus-floor elevation. In one side (test group) the sinus lift was performed with rhBMP-2 on a PLPG-sponge, while the contralateral side served as the control by using cancellous bone from the iliac crest. Three different implants (Bränemark®, 3i® and Straumann®) were inserted either simultaneously with the sinus augmentation or as a two staged procedure 6 weeks later. The animals were sacrificed at 6 and 12 weeks for histological and histomorphometrical evaluations during which bone-to-implant contact (BIC) and bone density (BD) were evaluated. Results: BD and BIC were significantly higher at 12 weeks in the test group if the implants were placed at the time of the sinus lift (p < 0.05). No difference was observed between the different implant systems or positions. Conclusions: The use of rhBMP-2 with PLPG-sponge increased BIC as well as BD in the augmented sinuses if compared to autologous bone. Different implant systems and positions of the implants had no effect on BIC or BD. © 2010 European Association for Cranio-Maxillo-Facial Surgery. Source


Ardjomandi N.,University Hospital of Tuebingen | Duttenhoefer F.,Albert Ludwigs University of Freiburg | Xavier S.,University of Sao Paulo | Oshima T.,Albert Ludwigs University of Freiburg | And 4 more authors.
Journal of Cranio-Maxillofacial Surgery | Year: 2015

Introduction The aim of this work was to analyse the suitability of mesenchymal stem cell isolation by FICOLL density centrifugation and the closed bone marrow aspirate concentrate (BMAC) system for sinus augmentation with bovine bone mineral (BBM) in the sheep model. Methods 16 sheep underwent sinus augmentation with BBM and MSCs; they were divided between two groups with survival points of 8 and 16 weeks. For the FICOLL control arm three, and for the BMAC test arm, five augmentations were performed for each time point. The derived cell numbers were counted; a colony forming unit (CFU) assay was performed; the pluripotency of the MSCs was proved; histological and histomorphometrical analysis were performed. Results The approach of using BBM and MSCs in combination with fibrin adhesive was sufficient for new bone formation as the FICOLL experiment indicated. However, due to significantly lower cell numbers isolated using the BMAC in sheep, less new bone was formed in the test arm. Conclusions The BMAC system is well suited for human MSC isolation but it needs to be optimized to fit sheep cell characteristics if it is to be used in this animal model. © 2015 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved. Source


Sauerbier S.,Albert Ludwigs University of Freiburg | Stubbe K.,Albert Ludwigs University of Freiburg | Maglione M.,University of Trieste | Haberstroh J.,Albert Ludwigs University of Freiburg | And 7 more authors.
Tissue Engineering - Part C: Methods | Year: 2010

Introduction: New reconstructive and less invasive methods have been searched to optimize bone formation and osseointegration of dental implants in maxillary sinus augmentation. Purpose: The aim of the presented ovine split-mouth study was to compare bovine bone mineral (BBM) alone and in combination with mesenchymal stem cells (MSCs) regarding their potential in sinus augmentation. Material and Methods: Bilateral sinus floor augmentations were performed in six adult sheep. BBM and MSCs were placed into the test side and only BBM in the contra-lateral control side of each sheep. Animals were sacrificed after 8 and 16 weeks. Augmentation sites were analyzed by computed tomography, histology, and histomorphometry. Results: The initial volumes of both sides were similar and did not change significantly with time. A tight connection between the particles of BBM and the new bone was observed histologically. Bone formation was significantly (p=0.027) faster by 49% in the test sides. Conclusion: The combination of BBM and MSCs accelerated new bone formation in this model of maxillary sinus augmentation. This could allow early placement of implants. © 2010, Mary Ann Liebert, Inc. Source


Kallali H.,Water Research and Technologies Center | Yoshida M.,Institute for International Cooperation | Tarhouni J.,National Institute of Agronomy INAT | Jedidi N.,Water Research and Technologies Center
Water Science and Technology | Year: 2013

The 'Cap Bon' peninsula in Tunisia suffers from intensive tourist activities, high demographic increase and industrial development. As groundwater had been for a long time the main water source, aquifers had been subject to a severe depletion and seawater intrusion. Despite the measures taken prohibiting new drillings and water carrying by the construction of a waterway linking the region to the north-west region of Tunisia, the problem of water shortage persists. Artificial recharge of groundwater with treated wastewater has been decided as a technique to replenish the region aquifers. A pilot plant was constructed in the early 1980s in Souhil Wadi (Nabeul) area. Many experiments have been carried out on this plant and have led to controversial opinions about its performance and its impact on groundwater contamination. This contribution concerns the application of the procedure that we developed from the generalization and the formalization of the United States Environmental Protection Agency (US EPA) methodology for the design of treated wastewater aquifer recharge basins. This upgrading procedure implemented in a spreadsheet, has been used to retrofit the Souhil Wadi facility in order to improve its performance. This method highlighted the importance of the safety factor to estimate wastewater infiltration rate from clean water permeability measurements. It has, also, demonstrated the discordance between the initial design parameters of Souhil Wadi facility and their current status as they have changed with time and the infiltration capacity of the basins has been affected by clogging. Indeed, it has been demonstrated that with the current state of clogging of the basins, the design infiltration rate limited by the most restrictive layer (6.1 cm/hr) corresponds to 22% of the surface infiltration rate reached after a drying period of 10 d, which means that we need more basins to absorb the daily loading rate. The design method leads to the construct ion of five basins of 961 m2 (31 × 31 m) each, with one basin being flooded for 3 d with 27 cm of water daily and rested for 10 d. The current status is completely different as only four basins are constructed with 324 m2 each. Many actions in the short, medium and long term have been advised in order to improve the system performance. © IWA Publishing 2013. Source

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