Comparative evaluation of the effects of lighting conditions on the shade selection of maxillary central incisor using visual methods

Abstract

Background: The selection of shade of a tooth is a routine practice for a dentist, especially a prosthodontist, to make esthetically pleasing prostheses. The phenomenon of colour is a matter of perception by the eye. Every opaque object receives light, absorbs some of it and reflects the rest. A tooth being an opaque object, reflects some amount of light. The dominant wavelength of this reflected light is discerned by us as the colour of the tooth. Light has variable properties that influence our perception. Daylight is regarded as the standard source for the selection of the colour of a tooth. Conversely, the lack of optimal circumstances during different times of the day necessitates using artificial illuminants to select shade of a tooth. This study was carried out to compare the accuracy of a shade-matching light (SMILE LINE) to that of standard daylight. Methods: This study followed the STROBE (Strengthening the Reporting of Observational Studies in Epidemiology) guidelines for cross-sectional studies. The study comprised 125 participants of ages ranging from 20 to 30 years. Five observers from the Department of Prosthodontics, Sharad Pawar Dental College (SPDC), Wardha selected the shade of the maxillary central incisor of 125 subjects under sunlight, dental operatory light, and shade-matching light. The statistical analysis was performed using the SPSS software, and Kappa statistics were used to compare the shades selected by the shade-matching light and dental operatory light with sunlight. Results: A strong correlation was discovered between the shades of tooth selected under the shade matching light and shades selected under sunlight for four out of five observers. Conclusions: The shade correcting device gives shades comparable to those selected under sunlight in ideal conditions making it useful as an alternative to sunlight for shade selection.