[Dissertations 25 year after date 18. Skin colour and facial prosthesis]

The traditional 'trial and error' methods for skin colour recording are not satisfactory. In 1982 a dissertation was published, titled 'Skin colour and facial prosthetics, a colorimetric study'. The dissertation was concerned with a clinical study of skin colour recording objectively in a random sample of 100 people, using subtraction colorimetry. Subsequently, facial prostheses were fabricated for a group of patients with a facial defect who had to undergo radiotherapy. From the results of the study the 3 following conclusions were drawn. Skin colour recording for producing a facial prosthesis need to be carried as close to the facial defect as possible. Alterations of skin colour are determined by light scattering in the skin as well as skin pigments. In patients with facial defects who have to undergo adjuvant radiotherapy, skin colour alterations are present until on average 13-14 weeks after completion of the radiotherapy and from that time point the skin colour remains rather stable. After publication of the dissertation, other research results demonstrated that light scattering in the skin, a sign of skin translucency, may be determined with a fiberoptic scattering meter (volume reflectometer). Using the fiberoptic scattering meter, a colour formula can be made, which by calculation shows the amount of pigments and scattering objects needed to produce the correct translucency and colour of a facial prosthesis. Currently, a small beam reflectometer is used for this purpose.