Novel Parallel Flow Chamber Investigations for Cellular Attachment

Anywhere from 25-35% of Americans are affected by periodontitis every year costing a significant portion of the nation’s yearly dental bill, which is expected to exceed $60 billion for 2000 according to The Surgeon General reports. Although the initial stage of inflammation is relatively painless, the advanced stages can be very painful. The initial stage of periodontitis is characterized as inflammation accompanied by periodontal ligament (PDL) detachment, forming a pocket greater than 3mm with final stages including bone and tooth loss. Objective:This research focuses on characterizing PDL attachment associated with all stages of periodontal disease. A novel parallel flow chamber has been developed in this laboratory to investigate cellular attachment to opaque surfaces including dentin. This system allows the chamber to be visualized by an episcopic microscope. Therefore, opaque materials can be placed in the chamber and the attached cells studied. Methods:For this pilot study, the design of the flow chamber was challenged by a range of flow rates corresponding to various shear forces. The designed flow chamber allows samples to be exposed to flow rates up to 10.8ml per min, which corresponds to 100dynes per cm2 (higher values were not tested). The samples were human third molars that have been extracted, mounted in polymethylmethacrylate (PMMA), and cut into 1mm thick slices. Silicon gaskets were used to isolate the flow to the surface of the dentin. Currently, PDL fibroblasts are being grown on the exposed dentin slices while a controlled, variable shear force is applied to determine the PDL fibroblasts strength of attachment. Results: A controlled range of flow rates corresponding to various shear forces was successively applied to the dentin surface. Conclusion:This novel test system will allow the affects of endotoxins, bacteriocides, mouthwashes, and Emdogain on PDL fibroblast attachment to dentin to be characterize.