Browsing by Author "WILLIAMS, DF"

Now showing 1 - 2 of 2
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    CURING OF VISIBLE LIGHT-ACTIVATED DENTAL RESTORATIVE COMPOSITES
    (BULLETIN OF MATERIALS SCIENCE, 1991) PAL, SN; VOWLES, R; WILLIAMS, DF
    FTIR spectroscopy and microhardness measurements were employed to follow the degree of curing of visible light activated dental composites. The observed dependence of curing on grade and shade of the materials, exposure time and depth from the light exposed surface have been discussed. Immediately after curing, it was found that direct correlation of microhardness values with that of double bond conversion estimated by FTIR technique could not be established.
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    EVALUATION OF SOFT-TISSUE RESPONSE TO A POLY(URETHANE UREA)
    (BIOMATERIALS, 1992) MOHANTY, M; HUNT, JA; DOHERTY, PJ; ANNIS, D; WILLIAMS, DF
    Variations in the performance of vascular prostheses constructed of polyurethanes, and some evidence which suggested that these variations could be due not to the properties of the polymer itself, but to differences in the cellular response to the various microstructures of porous polyurethanes require investigation. Experiments were performed to evaluate quantitatively the extent of the cell behaviour adjacent to a series of polyurethane samples. It was shown that, with Biomer(R), a polyurethane urea, the profile of cell behaviour as a function of distance from the implant surface and of time following implantation, the response of cells in general and macrophages in particular, varied considerably with different internal microstructure. This supports the suggestion that the cellular response to different structures and susceptibility to degradation are related.