LIFELIKENESS IN MULTILAYERED DIGITAL PROSTHESES

The appearance of the skin is dependent on the optical properties of t he various layers of tissue and the presence of pigments. In order to reproduce the lifelikeness of the skin in developing digital prosthese s, a multiple layered moulding technique was utilised. The prosthesis was moulded in two coloured layers, an outer layer and an inner layer. Four combinations of multiple coloured layers and two single coloured layers varying in their optical properties and base colours were asse ssed. In two groups an additional intermediate layer of detailed colou rs was added between the two layers, to enhance the creaselines, nails , blood vessels, and other features. All prosthesis were moulded to a total thickness of 0.6 mm. This method of moulding was based on the an atomical characteristics of the epidermal and dermal layers of the ski n and their optical characteristics. The aim was to determine which co mbination of multiple layers gave the best outcome and made the prosth esis look lifelike in appearance. The appearance and lifelikeness of t he prostheses were qualitatively assessed by a panel of assessers divi ded according to their vocation. The study showed that the best combin ation for moulding the prosthesis in multiple layers was to have the o uter layer translucent and the inner layer opaque. An intermediate lay er should be incorporated to enhance the more prominent surface featur es and the nails. The base colour of the inner layer should be darker than the outer layer to allow the intermediate layer to have a reflect ive background.