The ultimate objectives of this research are to develop, evaluate and apply a colorant formulation routine. This routine will specify the composition of polymeric dental and maxillofacial prosthetic materials in order to match natural tissue in color and opacity as closely as possible under many different illuminants. Existing research has shown that the light reflected by restorative porcelain materials is accurately modeled by a reflectance theory. This theory may then be used to define the color and opacity of any mixture of porcelains and differently colored pigments. However, the model found accurate for porcelain has failed for pigmented polymeric materials. Another model, through the use of additional optical constants, has been proposed for acrylic materials and was found to predict reflectance more precisely. This proposed research will first identify the appropriate model of optical reflectance of these prosthetic materials. This research will then incorporate the developed engineering principles regarding optical properties for mixtures with a recent color order system in order to derive a colorant formulation procedure capable of specifying the best color and translucency match with neighboring natural structures. Translucent vital human tissue displays unique optical characteristics which make an exact appearance match impossible for all daylight, tungsten, and fluorescent lighting conditions using currently available stable pigments. The major significance of this research is its fulfillment of the immediate need for an optimum colorant formulation routine and its ability to be utilized to evaluate the suitability of current and newly available pigments. The results of this research will increase the engineering knowledge needed to produce an esthetic polymeric prosthesis. For patients with severe facial trauma due to cancer or prosthesis. For patients with severe facial trauma due to cancer or injury, proper esthetics would encourage successful recovery by enhancing self-esteem and eliminating debilitating psychological stress.
| Johnston, W M; Hesse, N S; Davis, B K et al. (1996) Analysis of edge-losses in reflectance measurements of pigmented maxillofacial elastomer. J Dent Res 75:752-60 |
| Vickery, J M; Paulus, M W; Brantley, W A et al. (1995) Fundamental studies of maxillofacial materials: Part 1. Differential scanning calorimetric analyses of a heat-polymerized silicone. Int J Prosthodont 8:221-7 |
| Johnston, W M; Ma, T; Kienle, B H (1995) Translucency parameter of colorants for maxillofacial prostheses. Int J Prosthodont 8:79-86 |
| Davis, B K; Johnston, W M; Saba, R F (1994) Kubelka-Munk reflectance theory applied to porcelain veneer systems using a colorimeter. Int J Prosthodont 7:227-33 |
| Rugh, E H; Johnston, W M; Hesse, N S (1991) The relationship between elastomer opacity, colorimeter beam size, and measured colorimetric response. Int J Prosthodont 4:569-76 |
