Since bone tissues grow in intimate contact with implant surfaces in vivo, there is a need to investigate how bone cells respond to mechanical loads adjacent to implants under well characterized loading conditions that stimulate the bone-implant surface. Thus, the objective of this study was to demonstrate an effective means for applying known, uniform, cyclic strain to cells growing on implant materials in vitro. A cell culture strain plate device was developed based on the application of the four-point bending principle. The device uses a small electric motor to drive belts attached to shafts which turn a set of cams. The cams are attached to pins which connect to a titanium plate which rests over arched supports. When deflected and depending on which set of cams are used, strains generated range from around 200 to 1000 ìstrain. UMR-106 osteoblast-like cells were cultured on the titanium plate, and the plate was deflected at three strain magnitudes at 1.5 Hz for durations of 4 and 24 hours. Strain gages recorded average maximum strain levels of 182 ± 3, 366 ± 9, and 984 ± 7µstrain. The strain device, with attached cells, was tested in an amiable bioenvironment. Results from strain gages indicated a uniform strain field existed within the center region of the plate and culture area. Cells in the test plates stained viable, exhibited similar morphology to controls, and were assayed for alkaline phosphatase (ALP) activity, total protein production, and calcium deposition. Results also indicated that stretched cells exhibited increases in proliferation, as well as changes in ALP activity vs. unstrained controls. Thus, the device was successful in distinguishing differences in cell response to mechanical perturbations and may be used to investigate how cells respond to strains at implant-bone interfaces.
| Identifer | oai:union.ndltd.org:MSSTATE/oai:scholarsjunction.msstate.edu:td-1113 |
| Date | 03 August 2002 |
| Creators | Winter, Larry Chad |
| Publisher | Scholars Junction |
| Source Sets | Mississippi State University |
| Detected Language | English |
| Type | text |
| Format | application/pdf |
| Source | Theses and Dissertations |
Page generated in 0.0013 seconds