WESTLAND et al: COLOUR ASSESSMENT IN DENTISTRY 1 Annals of the BMVA Vol. 2007, No. 4, pp 1−10 (2007) Colour Assessment in Dentistry S. Westland, W. Luo, R. Ellwood 1 , P. Brunton and I. Pretty 2 University of Leeds, Leeds, UK 1 Dental Health Unit, Colgate-Palmolive, Manchester, UK 2 University of Manchester, Manchester, UK <s.westland@leeds.ac.uk> Abstract The colour of teeth is of considerable importance to the general population and the social and psychological impact of tooth discolouration is becoming increasingly less tolerated. A plethora of tooth-whitening systems (both for professional use and for use in the home) are now available and methods to assess the efficacy of such systems are required. In this paper an imaging system is described that can take reproducible images of patients’ teeth and methods are described for the colorimetric analysis of these images. The results of a clinical trial indicate that the imaging system that has been developed is effective for the clinical evaluation of tooth whiteness. 1 Introduction The colour of teeth is of considerable importance to the general population and the social and psychological impact of tooth discolouration is becoming increasingly less tolerated. It has been estimated, for example, that 28% of adults in the UK are dissatisfied with the appearance of their teeth [1] and that 34% of adults in the USA are similarly dissatisfied [2]. A more recent survey in the UK reported that up to 50% of adults perceived that they had some tooth discolouration [3]. Tooth colour is influenced by the intrinsic colour of the tooth and by any extrinsic stains that may form on the surface [4]. Intrinsic tooth colour is affected by the light-scattering and absorption properties of the enamel and dentine of the tooth itself but the enamel plays only a minor role through scattering at wavelengths in the blue range [5]. Fluorescence plays no role in tooth colour [5]. Stains result from poor dental hygiene and/or diet [6,7]. Tooth discolouration may be removed by a number of methods including the use of whitening toothpastes, dental scaling and polishing, bleaching, use of abrasive, and the use of crowns etc. Despite claims that tooth whitening may contribute to heightened self-esteem, improved oral hygiene and increased patient involvement with dentistry [8] its uptake by patients was relatively slow in the 1980s because of fears over © 2007. The copyright of this document resides with its authors. It may be distributed unchanged freely in print or electronic forms.