References of "Grenade, Charlotte"
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See detailFit of single tooth zirconia copings: comparison between various manufacturing processes.
Grenade, Charlotte ULg; MAINJOT, Amélie ULg; Vanheusden, Alain ULg

in Journal of Prosthetic Dentistry (2011), 105(4), 249-55

STATEMENT OF PROBLEM: Various CAD/CAM processes are commercially available to manufacture zirconia copings. Comparative data on their performance in terms of fit are needed. PURPOSE: The purpose of this ... [more ▼]

STATEMENT OF PROBLEM: Various CAD/CAM processes are commercially available to manufacture zirconia copings. Comparative data on their performance in terms of fit are needed. PURPOSE: The purpose of this in vitro study was to compare the internal and marginal fit of single tooth zirconia copings manufactured with a CAD/CAM process (Procera; Nobel Biocare) and a mechanized manufacturing process (Ceramill; Amann Girrbach). MATERIAL AND METHODS: Abutments (n=20) prepared in vivo for ceramic crowns served as a template for manufacturing both Procera and Ceramill zirconia copings. Copings were manufactured and cemented (Clearfil Esthetic Cement; Kuraray) on epoxy replicas of stone cast abutments. Specimens were sectioned. Nine measurements were performed for each coping. Over- and under-extended margins were evaluated. Comparisons between the 2 processes were performed with a generalized linear mixed model (alpha=.05). RESULTS: Internal gap values between Procera and Ceramill groups were not significantly different (P=.13). The mean marginal gap (SD) for Procera copings (51(50) mum) was significantly smaller than for Ceramill (81(66) mum) (P<.005). The percentages of over- and under-extended margins were 43% and 57% for Procera respectively, and 71% and 29% for Ceramill. CONCLUSIONS: Within the limitations of this in vitro study, the marginal fit of Procera copings was significantly better than that of Ceramill copings. Furthermore, Procera copings showed a smaller percentage of over-extended margins than did Ceramill copings. [less ▲]

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See detailEvaluation of the long-term barrier effect of commercial resorbable guided tissue regenerative membranes : an in vitro study using human gingival fibroblasts
Grenade, Charlotte ULg; Borget, Pascal; Moniotte, Nicolas et al

Poster (2009)

Introduction The first part of the study devoted to guided tissue regenerative membranes was focused on a better understanding of the physicochemical and mechanical properties of commercial materials. The ... [more ▼]

Introduction The first part of the study devoted to guided tissue regenerative membranes was focused on a better understanding of the physicochemical and mechanical properties of commercial materials. The second objective of our study was to develop an in vitro device able to measure the long-term barrier effect of resorbable membranes. After the development of this new device, experiments were realized to characterize the long-term behaviour of commercially membranes with human gingival fibroblasts (HGF). Materials and methods The use of human gingival fibroblastic cells was chosen to get closer to biological conditions. Some gingival explants were removed in young and non-smoking healthy patients. From these explants, fibroblastic cells were isolated and cultivated. These cells will be able to be used between the third and the sixth passage. Resorbable membranes were chosen because they don’t require a second surgical operation. There are made of polyesters or collagen. A system based on inserts was developed in order to follow the degradation of membranes and the migration of cells across the material. The membrane was cut into 8 mm diameter punches and set in the bottom of the system. Once the whole was put together, it is laced into a 12 wells plate culture. First, the plates were put in an incubator at 37°C, during times ranging from 24 hours to several months. The barrier effect was then measured to reflect the gradual increase of permeability of each membrane. For this purpose, HGF were seeded on the different samples. The top of the bottle and the bottom of the well were then filled with culture medium. Non degradable synthetic Bioflex membranes were chosen as control samples which don't let pass cells (porosity : 0,4 µm). After 48 hours of incubation in the presence of cells, pictures of cells on membranes and in the bottom of wells were taken with an optic microscope. Viability tests (MTS) were then realized on membranes to evaluate cells proliferation and in the bottom of wells to measure barrier effect. Finally, the morphology of cells on selected membranes was characterized by Scanning Electron Microscopy. Conclusion Proliferation results correspond to data published by several authors. Furthermore, the barrier effect times found in the present study are similar to barrier effect times demonstrated in in vivo studies and announced by manufacturers. In conclusion, the finalized system is adapted to the analysis of long-term barrier effect of commercial GTR membranes. This system will be tested with synthetic bioresorbable membranes made of copolymers. [less ▲]

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See detailMG-63 Osteoblast Culture on Biodegradable Textiles for Bone Tissue Regeneration
Moniotte, Nicolas; Borget, Pascal; Pirotte, Fabrice et al

Poster (2007)

The primary aim of bone scaffold is to restore, maintain and improve the structure and properties of damaged bones. The scaffold acts as a 3-D template for guided tissue-engineering and provides an ... [more ▼]

The primary aim of bone scaffold is to restore, maintain and improve the structure and properties of damaged bones. The scaffold acts as a 3-D template for guided tissue-engineering and provides an excellent transition from in vitro to in vivo systems, avoiding auto- or allo-grafting treatments, both associated with serious limitations. The pore size of the scaffold must be large enough to allow cell migration and proliferation through the structure, but small enough to provide sufficient specific area for cell attachment. In this work, degradable poly(lactic acid) (PLA) yarns were knitted into complexes superstructures and evaluated as 3-D scaffold to promote cell bone reconstruction. PLA fabrics were knitted from multi-filaments in a double layer interlock structure to produce a weft knit. The fabrics are made of two porosities, one defined by the open space inside a loop (~1mm) and the second by the distance between the filaments (1-10 µm), with high control and reproducibility inherent to the manufacturing process. Human MG-63 osteoblast-like cells were seeded on PLA textiles and cell viability and proliferation were evaluated using MTS (tetrazolium salt) assays, DNA quantitative analysis (hoechst), fluorescence staining (acridine orange) and scanning electron microscopy. Alkaline Phosphatase activity in cell lysates was also investigated. After 3 days of culture, MG-63 fully expressed their fibroblastic phenotype. Although the number of cells was high, mitochondrial activity was shown to be reduced when cells are on the PLA fibres (compared to culture on a glass slide). This may be due the release of lactic acid by slow hydrolysis of PLA ester-bonds. Only a small population of cells was dead. Furthermore, it could be due to cells in a less active phase, such as cells entering the G0 phase, or in a maturing phase. From 6 to 12 days, the number of cell inside the PLA fabrics increased and typical fibroblastic morphology was maintained. Cells were mainly observed in the spaces between fibres. After 24 days of culture, MG-63 colonization is covering all the PLA knit. Small granular structures are present on the cell surface and low ALP concentration is detected, indicating the beginning of the differentiation process, rather than a toxic effect of PLA hydrolysis. This work shows that knitted PLA fabrics, seeded with autogeneous osteoblast cells can potentially be used as tissue-engineered implants for the treatment of bone defects. [less ▲]

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See detailMG-63 osteoblasts culture on poly-(lactic acid) degradable textiles for bone tissue regeneration
Moniotte, Nicolas; Pirotte, Fabrice; Borget, Pascal et al

Article for general public (2007)

This work shows that knitted PLA fabrics, seeded with human MG-63 osteoblasts can potentially be used as tissue engineered systems for in vitro to in vivo transition, for the treatment of bone defect

Detailed reference viewed: 55 (11 ULg)