Supportive development of functional tissues for biomedical research using the MINUSHEET(R) perfusion system

Functional tissues generated under in vitro conditions are urgently needed in biomedical research. However, the engineering of tissues is rather difficult, since their development is influenced by numerous parameters. In consequence, a versatile culture system was developed to respond the unmet needs.Optimal adhesion for cells in this system is reached by the selection of individual biomaterials. To protect cells during handling and culture, the biomaterial is mounted onto a MINUSHEET(R) tissue carrier. While adherence of cells takes place in the static environment of a 24 well culture plate, generation of tissues is accomplished in one of several available perfusion culture containers. In the basic version a continuous flow of always fresh culture medium is provided to the developing tissue. In a gradient perfusion culture container epithelia are exposed to different fluids at the luminal and basal sides. Another special container with a transparent lid and base enables microscopic visualization of ongoing tissue development. A further container exhibits a flexible silicone lid to apply force onto the developing tissue thereby mimicking mechanical load that is required for developing connective and muscular tissue. Finally, stem/progenitor cells are kept at the interface of an artificial polyester interstitium within a perfusion culture container offering for example an optimal environment for the spatial development of renal tubules.The system presented here was evaluated by various research groups. As a result a variety of publications including most interesting applications were published. In the present paper these data were reviewed and analyzed. All of the results point out that the cell biological profile of engineered tissues can be strongly improved, when the introduced perfusion culture technique is applied in combination with specific biomaterials supporting primary adhesion of cells

Comparative Evaluation of the Effects of Ozone, Diode Laser, and Traditional Cavity Disinfectants on Microleakage

Aim: This study aimed to evaluate the effects on microleakage of the application of ozone gas, laser and traditional cavity disinfection under in vitro conditions. Material and Methods: Ninety third-molar teeth extracted for various reasons were used in this study. All the teeth were prepared with a standard V cavity on the buccal surface. Then the teeth were randomly allocated to one of 6 groups of 15 teeth; Group 1 benzalkonium chloride, Group 2 chlorhexidine gluconate, Group 3 sodium hypochloride, Group 4 diode laser, Group 5 ozone gas, Group 6 control group- no disinfection was applied. Primer was applied to the cavities, then bond and 10-s polymerization. Clearfil AP-X was used in the cavities as a hybrid composite and polymerized for 20 s. The samples then underwent 1000 thermal cycles of 30-s application, in baths at temperatures between 5 +/- 2 degrees C and 55 +/- 2 degrees C. All the samples were stirred in 0.5% basic phuxine solution and the sections taken under stereomicroscope were examined and photographed at 15 x magnification. SEM analysis was made and the obtained results were statistically evaluated with the Kruskal-Wallis test. Results: No significant difference was seen between the groups in respect of the microleakage values of both the occlusal and gingival edges (p < 0.05). Comparison of the microleakage values of the occlusal and gingival edges of the groups determined the least leakage to be in the ozone group (p < 0.05). Conclusion: No statistical significance was determined between the groups. However, the mean least microleakage was found in the ozone group and the highest amount in the control group.Dicle University Scientific Research Projects Co-ordination DepartmentThis study was supported by Dicle University Scientific Research Projects Co-ordination Department